/usr/share/doc/python-myghty/html/modulecomponents.html is in python-myghty 1.1-5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 | <html>
<head>
<title>
Myghty Documentation
</title>
<link href="style.css" rel="stylesheet" type="text/css"></link>
<link href="syntaxhighlight.css" rel="stylesheet" type="text/css"></link>
</head>
<body>
<link href="docs.css" rel="stylesheet" type="text/css"></link>
<div style="position:absolute;left:0px;top:0px;"><a name="top"></a> </div>
<div class="doccontainer">
<div class="docheader">
<div class="docheadertext" >Myghty Documentation</div>
<div class="">Version: 1.1 Last Updated: 09/10/06 19:32:29</div>
</div>
<A name="modulecomponents"></a>
<div class="topnav">
<div class="topnavcontrol">
View: <b>Paged</b> | <a href="documentation.html">One Page</a>
</div>
<div class="topnavsectionlink">
<a href="index.html">Table of Contents</a>
<div class="prevnext">
Previous: <a href="components.html">Components</a>
|
Next: <a href="request.html">The Request</a>
</div>
</div>
<div class="topnavmain">
<div class="topnavheader">Module Components</div>
<div class="topnavitems">
<div class="toclink">
<A style="" href="#modulecomponents_example">Example Module Component</a>
</div>
<div class="toclinkcontainer">
</div>
<div class="toclink">
<A style="" href="#modulecomponents_flavor">Flavors of Module Component</a>
</div>
<div class="toclinkcontainer">
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_flavor_function">Function</a>
</div>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_flavor_callable">Callable Object</a>
</div>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_flavor_method">Object Method</a>
</div>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_flavor_explicit">Class / Explicit Module Component</a>
</div>
</div>
</div>
<div class="toclink">
<A style="" href="#modulecomponents_initialization">Module Component Initialization</a>
</div>
<div class="toclinkcontainer">
</div>
<div class="toclink">
<A style="" href="#modulecomponents_controller">Using MCs as Controllers</a>
</div>
<div class="toclinkcontainer">
</div>
<div class="toclink">
<A style="" href="#modulecomponents_resolution">Configuring Module Component Resolution</a>
</div>
<div class="toclinkcontainer">
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_resolution_module_components">module_components</a>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_resolution_module_components_additional">Passing Resolution Arguments</a>
</div>
</div>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_resolution_module_root">module_root</a>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_resolution_module_root_options">Module Root Options</a>
</div>
</div>
</div>
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_resolution_routesresolver">Routes Resolver</a>
</div>
</div>
</div>
<div class="toclink">
<A style="" href="#modulecomponents_preprocessor">Module Component Pre and Post processing</a>
</div>
<div class="toclinkcontainer">
</div>
<div class="toclink">
<A style="" href="#modulecomponents_templates">Using Module Components within Templates</a>
</div>
<div class="toclinkcontainer">
<div class="toclinkcontainer">
<div class="smalltoclink">
<A href="#modulecomponents_templates_formexample">Example: Form Visitor</a>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="sectioncontent">
<div class="subsection" style="margin-left:10px;">
<div class="sectiontext">
<P>Module components build upon the component concept as introduced and explained in the previous section, <a href="components.html#components" >Components</a>. They represent a way of writing Myghty components using regular Python code within importable .py modules. A module component can be used to handle requests, controlling the flow of an application across one or more templates; this role is known as a "controller". Module components can also be embedded as component calls within templates just like any other component. In both cases, Module Components are the appropriate place to place code-intensive control or view logic.</p>
<p>Module Components, or MC's, are not a new idea, and have analogies in other environments, such as the Java Servlet class, the mod_python handler() function, or the WSGI application() callable. To suit the preferences of the both the class-oriented and the function-oriented developer, MC's can be written either as classes that subclass a specific Myghty class (similar to subclassing the Java Servlet class) or just as a regular Python function or callable object (i.e., an object instance that has a __call__ method). Additionally, individual methods upon a class instance can also be called as MC's. </p>
<p>When a plain Python function, callable object, or arbitrary instance method (herein will be generically referred to as a "callable") is to be called as a Module Component, the resulting component is referred to as an <b>implicit</b> module component. In this case, the Myghty Interpreter is given the location of the callable either via a string pattern or via passing the callable itself, and is told to execute it as a component. The Interpreter then creates a "real" component behind the scenes which <i>proxies</i> the Myghty argument set to the callable. The developer need not be aware of this proxying component (though it is available).
</p>
<p>The flipside to the implicit module component is the <b>explicit</b> module component. Here, the developer creates a class that is a subclass of <span class="codeline">myghty.component.ModuleComponent</span>, and implements the method <span class="codeline">do_run_component()</span>, which satisfies the execution of the component. Like the implicit module component, the Interpreter is given its location either via a string pattern or via the Class object itself, and is told to execute it. The Interpreter, upon receiving a Class object, instantiates the class which becomes directly the component to be executed; no "proxy" component is created.
</p>
<p>The differences between implicit and explicit module components are mostly differences in style. The explicit form allows the developer more direct access to the flags, attributes, and argument lists of the component to be called, whereas the implicit form is more sparse, lightweight and flexible. Both styles can be mixed; essentially, the Intepreter receives the object and determines the calling style based on the type of object passed to it. In all cases, the rest of a Myghty application sees just more <span class="codeline">myghty.component.Component</span> objects, which have the same properties as any other component.
</p>
<p>An added layer of complexity to module components involves the configuration of URI resolution, which allows the mapping of arbitrary URI's to specific module component callables or classes based on different schemes. This is required for MC's that are to be called as the top-level, request-handling component. Myghty currently includes two methods of achieving this, which are described later in this section, as well as an API to allow any user-defined mapping algorithm (part of <a href="resolver.html#resolver" >Advanced Resolver Configuration</a>).</p>
</div>
<A name="modulecomponents_example"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Example Module Component</span>
<div class="sectiontext">
<p>Lets start with hello world. All we need to do is create a new .py file, called <span class="codeline">hello.py</span>, and place the following function inside it:</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">helloworld</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world !"</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p>That is the extent of the module component itself. Since it is a plain function, this is an "implicit" module component.</p>
<p>To call the component, the request object is given a string starting with the prefix "MODULE:", followed by the module name and name of the callable or class, separated by a colon. In a template it is one of the following:</p>
<div class="code">
<pre><span class="doctag"># inline
</span><span class="compcall"><& </span><span class="compname">MODULE:hello:helloworld </span><span class="compcall">&></span><span class="text">
</span><span class="doctag"># code
</span><span class="blocktag"><%python></span>
<span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">comp</span><span class="python_enclosure">(</span><span class="python_literal">"MODULE:hello:helloworld"</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="blocktag"></%python></span></pre></div>
<p>Alternatively (release 0.99b), the "MODULE:" prefix can also be an "at" sign as follows:</p>
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">@hello:helloworld </span><span class="compcall">&></span><span class="text">
</span><span class="blocktag"><%python></span>
<span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">comp</span><span class="python_enclosure">(</span><span class="python_literal">"@hello:helloworld"</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="blocktag"></%python></span></pre></div>
<p>
Both the module name and the callable/class name can contain any number of periods to represent sub-modules or sub-properties of the module. Suppose <span class="codeline">helloworld</span> was a property on an object:
</p>
<div class="code">
<pre><span class="python_name">hello </span><span class="python_operator">= </span><span class="python_name">object</span><span class="python_enclosure">()</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">doit</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world !"</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_name">hello</span><span class="python_operator">.</span><span class="python_name">helloworld </span><span class="python_operator">= </span><span class="python_name">doit</span><span class="python_operator"></span></pre></div>
<p>This component can be called as:</p>
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">MODULE:hello:hello.helloworld </span><span class="compcall">&></span></pre></div>
<p>or just:</p>
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">@hello:hello.helloworld </span><span class="compcall">&></span></pre></div>
<p>The callable can have any argument list, and even the <i>m</i> variable is optional (though highly recommended). Myghty uses the <span class="codeline">inspect</span> library to determine the desired arguments based on the callable's signature. (for the performance minded, this is done only once when the component is first loaded). Using the names present in the argument list, Myghty will determine which of the available global variables will be specified, as well as what required and optional component arguments this MC will require. The component arguments are configured in exactly the same way as a template-based component configures its <%ARGS> section.</p>
<P>So to our "hello world" lets add the current and optionally tomorrow's weather:</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">helloworld</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_operator">, </span><span class="python_name">today</span><span class="python_operator">, </span><span class="python_name">tomorrow </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world ! its a %s day today." </span><span class="python_operator">% </span><span class="python_name">today</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_keyword">if </span><span class="python_name">tomorrow </span><span class="python_keyword">is </span><span class="python_name">None</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"Don't know what it is tomorrow, though."</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_keyword">else</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"But tomorrow, it'll be %s" </span><span class="python_operator">% </span><span class="python_name">tomorrow</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p>This component can be called like these examples:</p>
<div class="code">
<pre><span class="doctag"># inline shorthand
</span><span class="compcall"><& </span><span class="compname">@hello:helloworld</span><span class="python_operator">, </span><span class="python_name">today</span><span class="python_operator">=</span><span class="python_literal">'sunny'</span><span class="python_operator"> </span><span class="compcall">&></span><span class="text">
</span><span class="doctag"># inline longhand
</span><span class="compcall"><& </span><span class="compname">MODULE:hello:helloworld</span><span class="python_operator">, </span><span class="python_name">today</span><span class="python_operator">=</span><span class="python_literal">'sunny'</span><span class="python_operator"> </span><span class="compcall">&></span><span class="text">
</span><span class="doctag"># code
</span><span class="blocktag"><%python></span>
<span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">comp</span><span class="python_enclosure">(</span><span class="python_literal">"MODULE:hello:helloworld"</span><span class="python_operator">, </span><span class="python_name">today</span><span class="python_operator">=</span><span class="python_literal">'cloudy'</span><span class="python_operator">, </span><span class="python_name">tomorrow</span><span class="python_operator">=</span><span class="python_literal">'rainy'</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="blocktag"></%python></span></pre></div>
<p>The argument list of a module component may specify any of the standard and/or user-configured global arguments (globals were introduced in <a href="globals.html#globals" >Standard Global Variables</a>). All arguments are passed by name, so the ordering is not important:
</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">handle_request</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_operator">, </span><span class="python_name">ARGS</span><span class="python_operator">, </span><span class="python_name">r</span><span class="python_operator">, </span><span class="python_name">s</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># ...</span><span class="python_operator"></span></pre></div>
<p>The above component specifies that it will receive the global variables <i>m</i>, <i>ARGS</i>, <i>r</i>, and <i>s</i>. It also defines <span class="codeline">**params</span>, so all remaining component arguments will be in this dictionary. A callable that defines simply <span class="codeline">**params</span> will receive <i>all</i> globals and component arguments within the dictionary.</p>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_flavor"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Flavors of Module Component</span>
<div class="sectiontext">
<p>A summary of the various styles of MC are as follows. For each of the below examples, assume the callable exists within a module named <span class="codeline">mylib.hello</span>:</p>
</div>
<A name="modulecomponents_flavor_function"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">Function</span>
<div class="sectiontext">
This is the most basic type of implicit module component.
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">helloworld</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world!"</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
Called as:
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">MODULE:mylib.hello:helloworld </span><span class="compcall">&></span></pre></div>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_flavor_callable"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">Callable Object</span>
<div class="sectiontext">
<p>A callable object must be instantiated, but to the outside world looks almost the same as a function:</p>
<div class="code">
<pre><span class="python_keyword">class </span><span class="python_name">HelloWorld</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">__call__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world!"</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># instantiate the class
</span><span class="python_operator"></span><span class="python_name">helloworld </span><span class="python_operator">= </span><span class="python_name">HelloWorld</span><span class="python_enclosure">()</span><span class="python_operator"></span></pre></div>
Called as:
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">MODULE:mylib.hello:helloworld </span><span class="compcall">&></span></pre></div>
Note that this is identical to the previous function example.
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_flavor_method"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">Object Method</span>
<div class="sectiontext">
The object method is set up similarly to a callable object, the only difference being that a specific named method is called, instead of the generic <span class="codeline">__call__</span> method. The difference lies in how it is specified when called.
<div class="code">
<pre><span class="python_keyword">class </span><span class="python_name">HelloWorld</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">doit</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world!"</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># instantiate the class
</span><span class="python_operator"></span><span class="python_name">helloworld </span><span class="python_operator">= </span><span class="python_name">HelloWorld</span><span class="python_enclosure">()</span><span class="python_operator"></span></pre></div>
Called as:
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">MODULE:mylib.hello:helloworld.doit </span><span class="compcall">&></span></pre></div>
One particular quirk about the object method style is that if an object instance contains multiple methods that are called as MC's, the interpreter creates a <i>separate</i> "proxy" component for each method.</p>
<p>With both callable object styles, the <i>same</i> object instance handles <i>many</i> requests, including multiple simultaneous requests among different threads, if the application is running in a threaded environment. A developer should take care to store request-scoped information as attributes upon the request object and <i>not</i> as instance variables of the object, as well as to appropriately synchronize access to instance variables and module attributes.
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_flavor_explicit"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">Class / Explicit Module Component</span>
<div class="sectiontext">
<p>This style works differently from the previously mentioned styles, in that the developer is writing a class directly against the Myghty API. In this style, the developer directly defines the class of the component that is ultimately being accessed by the outside world. No "proxying" component is created; instead, the Interpreter instantiates the specified class the first time it is referenced. This also removes the need to explicitly instantiate the class:
<div class="code">
<pre><span class="python_keyword">import </span><span class="python_name">myghty</span><span class="python_operator">.</span><span class="python_name">component</span><span class="python_operator">
</span>
<span class="python_keyword">class </span><span class="python_name">HelloWorld</span><span class="python_enclosure">(</span><span class="python_name">myghty</span><span class="python_operator">.</span><span class="python_name">component</span><span class="python_operator">.</span><span class="python_name">ModuleComponent</span><span class="python_enclosure">)</span><span class="python_operator">:
</span>
<span class="python_operator"> </span><span class="python_keyword">def </span><span class="python_name">do_run_component</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world!"</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
Called as:
<div class="code">
<pre><span class="compcall"><& </span><span class="compname">MODULE:mylib.hello:HelloWorld </span><span class="compcall">&></span></pre></div>
<p>Note that the scoping rules for this style of component are the same, i.e. the same component instance is called for many requests and must be aware of variable scope as well as concurrency issues.</p>
<p>The <span class="codeline">do_run_component</span> method works similarly to the callable of an implicit component. Its argument list is dynamically inspected to determine the desired globals and component arguments, in the same way as that of implicit MC's. However, there also is the option to bypass this inspection process and name the arguments explicitly, as well as their desired scope. In previous versions of Myghty, this was the only way to define the arguments of an MC, but now its only optional. This method is described in the next section, as well as the configuration of flags and attributes for MC's.
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
</div>
<A name="modulecomponents_initialization"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Module Component Initialization</span>
<div class="sectiontext">
<p>Explicit MCs as well as implicit MCs based on an object instance have an optional initialization step that is called the first time the object instance is referenced. The method is called on an explicit ModuleComponent subclass as:
</p>
<span class="code">def do_component_init(self)</span>
<p>
And is called on an implicit callable object as:
</p>
<span class="code">def do_component_init(self, component)</span>
<p>In the second version, the argument <span class="codeline">component</span> is an instance of <span class="codeline">myghty.component.FunctionComponent</span> that is <b>hosting</b> the implicit module component's <span class="codeline">__call__</span> method or other method. It is important to note that an object instance with many callable methods will actually have many FunctionComponents created, each one hosting an individual methods...<b>however</b>, the do_component_init() method is only called <b>once</b> with whatever FunctionComponent was first associated with the object.</p>
<p> In previous versions of Myghty, the initialization phase was required for components with arguments, which had to be explicitly declared within this stage. As of version 0.98, explicit declaration of component arguments is optional, and the argument lists are by default determined from the signature of the explicit <span class="codeline">do_run_component</span> method or the implicit callable.</p>
<p>Explicit specification of an MCs arguments in the init section are as follows:</p>
<div class="code">
<pre><span class="python_keyword">import </span><span class="python_name">myghty</span><span class="python_operator">.</span><span class="python_name">component </span><span class="python_keyword">as </span><span class="python_name">component</span><span class="python_operator">
</span>
<span class="python_keyword">class </span><span class="python_name">MyComponent</span><span class="python_enclosure">(</span><span class="python_name">component</span><span class="python_operator">.</span><span class="python_name">ModuleComponent</span><span class="python_enclosure">)</span><span class="python_operator">:
</span>
<span class="python_operator"> </span><span class="python_keyword">def </span><span class="python_name">do_component_init</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># component arguments
</span><span class="python_operator"> </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'arg1'</span><span class="python_operator">, </span><span class="python_literal">'arg2'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_comment"># required component arguments
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">required_args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'arg3'</span><span class="python_operator">, </span><span class="python_literal">'arg4'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_comment"># request-only arguments
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">request_args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'docid'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_comment"># required request-only arguments
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">required_request_args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'userid'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_comment"># subrequest or request arguments
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">subrequest_args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'foo'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_comment"># required subrequest or request arguments
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">required_subrequest_args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'bar'</span><span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
<p>
A component as above would have the <span class="codeline">do_run_component</span> signature as follows:
</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">do_run_component</span><span class="python_enclosure">(</span>
<span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, </span><span class="python_name">userid</span><span class="python_operator">, </span><span class="python_name">arg3</span><span class="python_operator">, </span><span class="python_name">arg4</span><span class="python_operator">, </span><span class="python_name">bar</span><span class="python_operator">, </span>
<span class="python_name">docid </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_operator">, </span><span class="python_name">arg1 </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_operator">, </span><span class="python_name">arg2 </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_operator">, </span><span class="python_name">foo </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_operator">, **</span><span class="python_name">params</span>
<span class="python_enclosure">)</span><span class="python_operator">:</span></pre></div>
<p>Note that if a module component defines any arguments explicitly in the do_component_init method, all arguments for the do_run_component method must be specified; no automatic introspection of function arguments will occur.</p>
<p>Similarly, <%flags> and <%attr> sections can be achieved like this:
</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">do_component_init</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># flags
</span><span class="python_operator"> </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">flags </span><span class="python_operator">= </span><span class="python_enclosure">{</span>
<span class="python_literal">'autoflush'</span><span class="python_operator">:</span><span class="python_name">True</span><span class="python_operator">,</span>
<span class="python_literal">'trim'</span><span class="python_operator">: </span><span class="python_literal">'both'</span>
<span class="python_enclosure">}</span><span class="python_operator">
</span>
<span class="python_comment"># attributes
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">attr </span><span class="python_operator">= </span><span class="python_enclosure">{</span>
<span class="python_literal">'style'</span><span class="python_operator">:</span><span class="python_literal">'green'</span><span class="python_operator">,</span>
<span class="python_literal">'docid'</span><span class="python_operator">:</span><span class="python_number">5843</span>
<span class="python_enclosure">}</span><span class="python_operator"></span></pre></div>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_controller"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Using MCs as Controllers</span>
<div class="sectiontext">
<p>The two most prominent features of an MC used as a controller includes that URI resolution is configured so that one or more URIs result in the component being called directly from a request, and that the component typically uses subrequests to forward execution onto a template, which serves as the view.</p>
<p>Here are two versions of a controller component that is used to pull documents from a database based on the request arguments, and displays them via a template called "documents.myt".
</p>
<p><b>Figure 1: Implicit Style, using a Callable Object</b></p>
<div class="code">
<pre>
<span class="python_operator"> </span><span class="python_keyword">class </span><span class="python_name">DocumentManager</span><span class="python_operator">:
</span>
<span class="python_operator"> </span><span class="python_keyword">def </span><span class="python_name">do_component_init</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">component</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># load some application-wide constants via Interpreter attributes.
# the Interpreter is located via the hosting component.
</span><span class="python_operator"> </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">document_base </span><span class="python_operator">= </span><span class="python_name">component</span><span class="python_operator">.</span><span class="python_name">interpreter</span><span class="python_operator">.</span><span class="python_name">attributes</span><span class="python_enclosure">[</span><span class="python_literal">'document_base'</span><span class="python_enclosure">]</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">db_string </span><span class="python_operator">= </span><span class="python_name">component</span><span class="python_operator">.</span><span class="python_name">interpreter</span><span class="python_operator">.</span><span class="python_name">attributes</span><span class="python_enclosure">[</span><span class="python_literal">'db_connect_string'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">__call__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, </span><span class="python_name">docid </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_enclosure">)</span><span class="python_operator">:
</span>
<span class="python_comment"># if no document id, return '404 - not found'
</span><span class="python_operator"> </span><span class="python_keyword">if </span><span class="python_name">docid </span><span class="python_keyword">is </span><span class="python_name">None</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">abort</span><span class="python_enclosure">(</span><span class="python_number">404</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># access a hypothetical document database
</span><span class="python_operator"></span><span class="python_name">docdb </span><span class="python_operator">= </span><span class="python_name">get_doc_db</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">document_base</span><span class="python_operator">, </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">db_string</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># load document
</span><span class="python_name">document </span><span class="python_operator">= </span><span class="python_name">docdb</span><span class="python_operator">.</span><span class="python_name">find_document</span><span class="python_enclosure">(</span><span class="python_name">docid</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># couldnt find document - return '404 - not found'
</span><span class="python_keyword">if </span><span class="python_name">document </span><span class="python_keyword">is </span><span class="python_name">None</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">abort</span><span class="python_enclosure">(</span><span class="python_number">404</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># run template
</span><span class="python_operator"></span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">subexec</span><span class="python_enclosure">(</span><span class="python_literal">'documents.myt'</span><span class="python_operator">, </span><span class="python_name">document </span><span class="python_operator">= </span><span class="python_name">document</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_name">documentmanager </span><span class="python_operator">= </span><span class="python_name">DocumentManager</span><span class="python_enclosure">()</span><span class="python_operator"></span></pre></div>
<p><b>Figure 2: Explicit Style, with Pre-Declared Arguments</b></p>
<div class="code">
<pre><span class="python_keyword">import </span><span class="python_name">myghty</span><span class="python_operator">.</span><span class="python_name">component </span><span class="python_keyword">as </span><span class="python_name">component</span><span class="python_operator">
</span>
<span class="python_keyword">class </span><span class="python_name">DocumentManager</span><span class="python_enclosure">(</span><span class="python_name">component</span><span class="python_operator">.</span><span class="python_name">ModuleComponent</span><span class="python_enclosure">)</span><span class="python_operator">:
</span>
<span class="python_operator"> </span><span class="python_keyword">def </span><span class="python_name">do_component_init</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># load some application-wide constants
</span><span class="python_operator"> </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">document_base </span><span class="python_operator">= </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">interpreter</span><span class="python_operator">.</span><span class="python_name">attributes</span><span class="python_enclosure">[</span><span class="python_literal">'document_base'</span><span class="python_enclosure">]</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">db_string </span><span class="python_operator">= </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">interpreter</span><span class="python_operator">.</span><span class="python_name">attributes</span><span class="python_enclosure">[</span><span class="python_literal">'db_connect_string'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_comment"># establish the argument names we want (optional as of 0.98)
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">args </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'docid'</span><span class="python_enclosure">]</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">do_run_component</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, </span><span class="python_name">ARGS</span><span class="python_operator">, </span><span class="python_name">docid </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span>
<span class="python_comment"># if no document id, return '404 - not found'
</span><span class="python_operator"> </span><span class="python_keyword">if </span><span class="python_name">docid </span><span class="python_keyword">is </span><span class="python_name">None</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">abort</span><span class="python_enclosure">(</span><span class="python_number">404</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># access a hypothetical document database
</span><span class="python_operator"></span><span class="python_name">docdb </span><span class="python_operator">= </span><span class="python_name">get_doc_db</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">document_base</span><span class="python_operator">, </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">db_string</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># load document
</span><span class="python_name">document </span><span class="python_operator">= </span><span class="python_name">docdb</span><span class="python_operator">.</span><span class="python_name">find_document</span><span class="python_enclosure">(</span><span class="python_name">docid</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># couldnt find document - return '404 - not found'
</span><span class="python_keyword">if </span><span class="python_name">document </span><span class="python_keyword">is </span><span class="python_name">None</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">abort</span><span class="python_enclosure">(</span><span class="python_number">404</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># run template
</span><span class="python_operator"></span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">subexec</span><span class="python_enclosure">(</span><span class="python_literal">'documents.myt'</span><span class="python_operator">, </span><span class="python_name">document </span><span class="python_operator">= </span><span class="python_name">document</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p>
The next section describes the two methods of configuring request URIs to execute "controller" components like this one.
</p>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_resolution"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Configuring Module Component Resolution</span>
<div class="sectiontext">
<p>
Module components can be used anywhere within the request, either right at the beginning (i.e. a controller) or within the scope of other components already executing. A module component can be fetched and/or called based on its importable module name followed by a path to a callable object, or the name of a class that subclasses <span class="codeline">myghty.components.ModuleComponent</span>. However, this doesn't work as a URL sent to a webserver. For request-level operation, MCs must be mapped to URIs. This resolution is achieved through two different configuration directives, <span class="codeline">module_components</span> and <span class="codeline">module_root</span>. A third option also exists which is to use the new <span class="codeline">routesresolver</span> resolver object.</p>
</div>
<A name="modulecomponents_resolution_module_components"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">module_components</span>
<div class="sectiontext">
The module_components configuration parameter looks like this:
<div class="code">
<pre><span class="python_name">module_components </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_enclosure">{</span><span class="python_literal">r'myapplication/home/.*' </span><span class="python_operator">: </span><span class="python_literal">'myapp.home:HomeHandler'</span><span class="python_enclosure">}</span><span class="python_operator">, </span>
<span class="python_enclosure">{</span><span class="python_literal">r'myapplication/login/.*' </span><span class="python_operator">: </span><span class="python_literal">'myapp.login:LoginHandler'</span><span class="python_enclosure">}</span><span class="python_operator">, </span>
<span class="python_enclosure">{</span><span class="python_literal">r'.*/cart' </span><span class="python_operator">: </span><span class="python_literal">'myapp.cart:process_cart'</span><span class="python_enclosure">}</span><span class="python_operator">, </span>
<span class="python_enclosure">{</span><span class="python_literal">r'.*' </span><span class="python_operator">: </span><span class="python_literal">'myapp.home:HomeHandler'</span><span class="python_enclosure">} </span>
<span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
Which in an apache configuration looks like:
<div class="code">
<pre>PythonOption MyghtyModuleComponents "[ \
{r'myapplication/home/.*' : 'myapp.home:HomeHandler'}, \
{r'myapplication/login/.*' : 'myapp.login:LoginHandler'}, \
{r'.*/cart' : 'myapp.cart:ShoppingCart'}, \
{r'.*' : 'myapp.home:HomeHandler'} \
]"</pre></div>
<p>
Each entry in the module_components array is a single-member hash containing a regular expression to be matched against the incoming URI, and an expression that can be resolved into a Module Component. This expression can be any of the following forms:
</p>
<div class="code">
<pre><span class="python_name">module_components </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_comment"># a string in the form '<modulename>:<classname>' </span>
<span class="python_enclosure">{</span><span class="python_literal">r'myapplication/home/.*' </span><span class="python_operator">: </span><span class="python_literal">'myapp.home:HomeHandler'</span><span class="python_enclosure">}</span><span class="python_operator">, </span>
<span class="python_comment"># a string in the form '<modulename>:<functionname>'</span>
<span class="python_enclosure">{</span><span class="python_literal">r'myapplication/login/.*' </span><span class="python_operator">: </span><span class="python_literal">'myapp.login:do_login'</span><span class="python_enclosure">}</span><span class="python_operator">, </span>
<span class="python_comment"># a string in the form '<modulename>:<some>.<callable>.<thing>'</span>
<span class="python_enclosure">{</span><span class="python_literal">r'myapplication/status/.*' </span><span class="python_operator">: </span><span class="python_literal">'myapp.status:handler.mcomp.get_status'</span><span class="python_enclosure">}</span><span class="python_operator">,</span>
<span class="python_comment"># a Class</span>
<span class="python_enclosure">{</span><span class="python_literal">r'.*/cart' </span><span class="python_operator">: </span><span class="python_name">MyClass</span><span class="python_enclosure">}</span><span class="python_operator">, </span>
<span class="python_comment"># a function reference, or reference to a callable() object</span>
<span class="python_enclosure">{</span><span class="python_literal">r'.*/dostuff' </span><span class="python_operator">: </span><span class="python_name">do_stuff</span><span class="python_enclosure">}</span><span class="python_operator">,</span>
<span class="python_comment"># reference to a class instance method</span>
<span class="python_enclosure">{</span><span class="python_literal">r'.*' </span><span class="python_operator">: </span><span class="python_name">mymodule</span><span class="python_operator">.</span><span class="python_name">processor</span><span class="python_operator">.</span><span class="python_name">main_process</span><span class="python_enclosure">}</span>
<span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
<p>
Generally, its better to use the string forms since they encompass all the information needed to load the class or callable object, which allows the Myghty interpreter to dynamically reload the object when the underlying module has changed.
</p>
<p>For module components that resolve to a Class, the Class will be instantiated by the Interpreter, and is expected to be a subclass of <span class="codeline">myghty.component.ModuleComponent</span>. This is also known as an <b>explicit</b> module component. For components that resolve to a function, object instance method, or callable object (i.e. any object that has a __call__ method), a "wrapper" module component will be created automatically which adapts to the callable's argument list. This is also known as an <b>implicit</b> module component.
</p>
<p>The corresponding Resolver class for module_components is ResolveModule.
</p>
</div>
<A name="modulecomponents_resolution_module_components_additional"></a>
<div class="subsection" style="margin-left:40px;">
<span class="sectionheadertext">Passing Resolution Arguments</span>
<div class="sectiontext">
<p>The module_components configuration parameter also includes some methods of returning information about the actual resolution of the component at request time.</p>
<p>Since module_components uses regular expressions to match URIs to components, the <span class="codeline">re.Match</span> object produced when a match occurs can be accessed via the <i>m</i> global variable. This example places capturing parenthesis in the regular expression to capture the additional path information:</p>
<div class="code">
<pre><span class="python_name">module_components </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_comment"># place capturing parenthesis in the regexp</span>
<span class="python_enclosure">{</span><span class="python_literal">r'/catalog/(.*)' </span><span class="python_operator">: </span><span class="python_literal">'store:Catalog'</span><span class="python_enclosure">}</span>
<span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
The contents of the capturing parenthesis are available as:
<div class="code">
<pre><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">resolution</span><span class="python_operator">.</span><span class="python_name">match</span><span class="python_operator">.</span><span class="python_name">group</span><span class="python_enclosure">(</span><span class="python_number">1</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p>User-defined arguments can also be configured which will be passed to the request object at resolution time. To use this form, a dictionary is used instead of a single string to specify the module and callable/class name of the component, and the address of the component itself is placed under the key 'component':</p>
<div class="code">
<pre><span class="python_name">module_components </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_comment"># supply the component with some arguments</span>
<span class="python_enclosure">{</span><span class="python_literal">r'/login/' </span><span class="python_operator">: </span>
<span class="python_enclosure">{</span>
<span class="python_literal">'component' </span><span class="python_operator">: </span><span class="python_literal">'myapp:loginmanager'</span><span class="python_operator">,</span>
<span class="python_literal">'ldap_server' </span><span class="python_operator">: </span><span class="python_literal">'ldap://localhost:5678'</span>
<span class="python_enclosure">}</span>
<span class="python_enclosure">}</span>
<span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
The contents of the <span class="codeline">ldap_server</span> argument are available as:
<div class="code">
<pre><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">resolution</span><span class="python_operator">.</span><span class="python_name">args</span><span class="python_enclosure">[</span><span class="python_literal">'ldap_server'</span><span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
</div>
<A name="modulecomponents_resolution_module_root"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">module_root</span>
<div class="sectiontext">
<p>This parameter locates module components based on paths. It is similar to the <a href="params.html#parameters_component_root" >component_root</a> configuration parameter in that it defines one or more roots which will all be matched against the incoming URI. However, it not only traverses through directories, it also will traverse into a Python module where it attempts to locate a function or callable object instance. Currently, only the "implicit" style of module components can be used with module_root (but module_components, from the previous section, can be used with implicit or explicit MCs).
</p>
<p>The entries in module_root take the following forms:</p>
<div class="code">
<pre><span class="python_name">module_root </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_comment"># a regular file path</span>
<span class="python_literal">'/web/lib/modules/'</span><span class="python_operator">,</span>
<span class="python_comment"># the full file path of a Python module</span>
<span class="python_literal">'/web/extra/modules/mycontroller.py'</span><span class="python_operator">,</span>
<span class="python_comment"># the name of an importable Python module</span>
<span class="python_literal">'mylib.loginhandlers'</span><span class="python_operator">,</span>
<span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
<p>Using the first path '/web/lib/modules', heres an example. Start with the following file:</p>
<div class="code">
<pre>/web/lib/modules/admin/login.py</pre></div>
<p>This file contains the following code:</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">hello</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"hello world!"</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">_do_login</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">__call__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"please login"</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_comment"># ....
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">foo</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_literal">"this is foo"</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_name">index </span><span class="python_operator">= </span><span class="python_name">_do_login</span><span class="python_enclosure">()</span><span class="python_operator">
</span>
<span class="python_name">_my_var </span><span class="python_operator">= </span><span class="python_number">12</span><span class="python_operator"></span></pre></div>
<p>Finally, lets have a module_root of:</p>
<div class="code">
<pre><span class="python_name">module_root </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'/web/lib/modules'</span><span class="python_enclosure">]</span><span class="python_operator"></span></pre></div>
<p>With this configuration, URLs will be resolved as follows:</p>
<div class="code">
<pre>http://mysite.com/admin/login/hello/ ---> "hello world!" (login.py:hello())
http://mysite.com/admin/login/ ---> "please login" (login.py:index.__call__())
http://mysite.com/admin/login/foo/ ---> "this is foo" (login.py:index.foo())
http://mysite.com/admin/login/lala/ ---> "please login" (login.py:index.__call__())
http://mysite.com/admin/login/_my_var/ ---> "please login" (_my_var is private and is skipped)
http://mysite.com/admin/lala/ ---> 404 not found (no file named lala.py)</pre></div>
<p>The spirit of this resolver is that of the mod_python Publisher handler. Path tokens are converted into the names of .py files on the filesystem. When a file is located and it is a valid Python module, the module is loaded and further path tokens are resolved as attributes within the module itself. Attributes that start with an underscore are skipped, which is the default way to flag "private" attributes. There is also a "public" attribute marker which can be used to mark public functions instead of marking private functions, explained in the options section below. If no matching attribute exists for a path token, it looks for the attribute name "index", else returns a ComponentNotFound exception.
</p>
<p>module_root can also be combined with dhandler resolution (described in <a href="specialtempl.html#specialtempl_dhandler" >dhandler</a>), so that a file named <span class="codeline">dhandler.py</span> in the current or parent directory serves as the "default" Python module for a path token that does not correspond to any other file. In the case of ResolvePathModule locating a dhandler.py file, the additional path tokens that normally reside within <a href="request.html#request_members_dhandler_path" >dhandler_path</a> are also searched as attributes within the dhandler.py module.
</p>
<p>The corresponding Resolver class for module_root is ResolvePathModule.
</p>
</div>
<A name="modulecomponents_resolution_module_root_options"></a>
<div class="subsection" style="margin-left:40px;">
<span class="sectionheadertext">Module Root Options</span>
<div class="sectiontext">
<p>The underlying Resolver object for the module_root parameter is called ResolvePathModule (resolver objects are described in <a href="resolver.html#resolver" >Advanced Resolver Configuration</a>). This object also has configuration options of its own. These options may be specified to the ResolvePathModule constructor directly. They can be specified as regular Myghty configuration parameters as well as of version 0.99b:
<ul>
<li><p>module_root_adjust=None (release 0.99b) - a reference to a function which receives the incoming URI and returns a modified version of that URI with which to resolve. The modified URI is not propigated onto other rules in the resolution chain, so therefore it represents a "local" alternative to <a href="params.html#parameters_path_translate" >path_translate</a>.</p>
<p>This parameter is also called 'adjust' in all releases, but that name conflicts with the same name in the ResolveFile resolver, so should only be used when constructing individual ResolvePathModule objects and not as a global configuration parameter.</p>
</li>
<li><p>require_publish=False - when set to True, the callable object must have an attribute <span class="codeline">publish</span> set to True in order to mark it as publically accessible; else it will not be resolved. This effectively reverses the "negative publishing" model established via the underscore "_" syntax into a "positive publishing" model. Given this configuration:</p>
<div class="code">
<pre><span class="python_name">module_root </span><span class="python_operator">= </span><span class="python_enclosure">[</span><span class="python_literal">'/web/lib/modules'</span><span class="python_enclosure">]</span><span class="python_operator">
</span><span class="python_name">require_publish </span><span class="python_operator">= </span><span class="python_name">True</span><span class="python_operator"></span></pre></div>
<p>Marking functions and methods public looks like this:
<div class="code">
<pre><span class="python_keyword">class </span><span class="python_name">MyController</span><span class="python_enclosure">(</span><span class="python_name">object</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">__call__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">kwargs</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># ...
</span><span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">subexec</span><span class="python_enclosure">(</span><span class="python_literal">'mytemplate.myt'</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_name">__call__</span><span class="python_operator">.</span><span class="python_name">public </span><span class="python_operator">= </span><span class="python_name">True</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">do_stuff</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">kwargs</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># ...
</span><span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">subexec</span><span class="python_enclosure">(</span><span class="python_literal">'dostuff.myt'</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_name">do_stuff</span><span class="python_operator">.</span><span class="python_name">public </span><span class="python_operator">= </span><span class="python_name">True</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">call_index</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_operator">,</span><span class="python_name">r</span><span class="python_operator">, </span><span class="python_name">s</span><span class="python_operator">, </span><span class="python_name">ARGS</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># ...
</span><span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">subexec</span><span class="python_enclosure">(</span><span class="python_literal">'index.myt'</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_name">call_index</span><span class="python_operator">.</span><span class="python_name">public </span><span class="python_operator">= </span><span class="python_name">True</span><span class="python_operator">
</span>
<span class="python_name">mycallable </span><span class="python_operator">= </span><span class="python_name">MyController</span><span class="python_enclosure">()</span><span class="python_operator"></span></pre></div>
<p>The public attribute can also be set in Python 2.4 via decorator:</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">mark_public</span><span class="python_enclosure">(</span><span class="python_name">func</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">func</span><span class="python_operator">.</span><span class="python_name">public </span><span class="python_operator">= </span><span class="python_name">True</span><span class="python_operator">
</span><span class="python_keyword">return </span><span class="python_name">func</span><span class="python_operator">
</span>
<span class="python_operator">@</span><span class="python_name">mark_public</span><span class="python_operator">
</span><span class="python_keyword">def </span><span class="python_name">mycontroller</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">kwargs</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># ...</span><span class="python_operator"></span></pre></div>
</li>
<li>path_moduletokens=['index'] - this is a list of special "default" token names when searching for module attributes. For example: If a given path "/foo/bar/bat" resolves to the module "bar.py" inside of directory "foo/", it will first look for an attribute named "bat" inside the module. If "bat" is not present, it will then look for all the names inside the moduletokens list, which defaults to the single entry "index". Therefore /foo/bar/bat not only looks for "bat", it also looks for "index". The tokens inside moduletokens are checked as defaults for every module token, so that a path such as "/foo/bar/bat" can also correspond to a module attribute "foo.index.bat", "index.bar.bat", etc.</li>
<li>path_stringtokens=[] - this is the path equivalent to the moduletokens parameter. It is a list of "default" path tokens when searching for files. In some ways, this parameter's functionality overlaps that of <a href="params.html#parameters_dhandler_name" >dhandler_name</a>, except it allows multiple names and applies only to the module_root configuration. For example, if stringtokens is configured to ["default", "index"], and a given path "/foo/bar" resolves to the directory "foo/" but there is no file named "bar.py" inside the directory, it will then look for the files "default.py" and "index.py", respectively. Like moduletokens, stringtokens also checks these defaults for every path token, so a URL of "/foo/bar/bat" can also match "/default/bar/index", for example.</li>
</ul>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
</div>
<A name="modulecomponents_resolution_routesresolver"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">Routes Resolver</span>
<div class="sectiontext">
<P>The Routes Resolver provides Rails-like functionality, building upon the resolution architecture described in <a href="resolver.html#resolver" >Advanced Resolver Configuration</a>. Since it is not part of the default set of resolver objects, it must be included in the resolution chain via the <a href="params.html#parameters_resolver_strategy" >resolver_strategy</a> configuration parameter.</p>
<p>A rudimentary example of the Routes resolver can be viewed by installing the <span class="codeline">myghty_routes</span> Paste template. Instructions for installing Paste templates are in <a href="installation.html#installation_paste" >Running Paste Templates</a>. The routes resolver also serves as the core resolver for the <a href="http://pylons.groovie.org">Pylons</a> web framework which is based on Myghty, and includes more comprehensive and up-to-date examples.
</p>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
</div>
<A name="modulecomponents_preprocessor"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Module Component Pre and Post processing</span>
<div class="sectiontext">
<p>Request-handling module components can also be used to perform pre- and post-processing on a request. This means that the information about a request is modified before and/or after the main response is determined. The following two examples both wrap the main body of the request inside of a subrequest.</p>
<p>A module component that performs translations on incoming URI's, and then passes control onto the requested template, looks like this:</p>
<div class="code">
<pre><span class="python_keyword">def </span><span class="python_name">translate_path</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">path </span><span class="python_operator">= </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">get_request_path</span><span class="python_enclosure">()</span><span class="python_operator">
</span><span class="python_name">path </span><span class="python_operator">= </span><span class="python_name">re</span><span class="python_operator">.</span><span class="python_name">sub</span><span class="python_enclosure">(</span><span class="python_literal">'/sitedocs/john/'</span><span class="python_operator">, </span><span class="python_literal">'/'</span><span class="python_operator">, </span><span class="python_name">path</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">subexec</span><span class="python_enclosure">(</span><span class="python_name">path</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p>A URI configuration for this component might look like:</p>
<div class="code">
<pre><span class="python_name">module_components </span><span class="python_operator">= </span><span class="python_enclosure">[{</span><span class="python_literal">r'/sitedocs/john/.*\.myt'</span><span class="python_operator">, </span><span class="python_literal">'mymodule:translate_path'</span><span class="python_enclosure">}]</span><span class="python_operator"></span></pre></div>
<p>Path translation is also accomplished in Myghty via the <a href="params.html#parameters_path_translate" >path_translate</a> parameter, and can be controlled in finer detail through the use of custom resolution rules, described in <a href="resolver.html#resolver" >Advanced Resolver Configuration</a>.</p>
<p>An example post processing component, which filters the output of the subrequest before returning data:
</p>
<div class="code">
<pre><span class="python_keyword">import </span><span class="python_name">StringIO</span><span class="python_operator">, </span><span class="python_name">re</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">filter</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_comment"># make a buffer
</span><span class="python_operator"> </span><span class="python_name">buf </span><span class="python_operator">= </span><span class="python_name">StringIO</span><span class="python_operator">.</span><span class="python_name">StringIO</span><span class="python_enclosure">()</span><span class="python_operator">
</span>
<span class="python_comment"># create a subrequest using that buffer
# our templates are located relative to the
# request URI underneath '/components'
</span><span class="python_name">subreq </span><span class="python_operator">= </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">create_subrequest</span><span class="python_enclosure">(</span><span class="python_literal">'/components' </span><span class="python_operator">+ </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">get_request_uri</span><span class="python_enclosure">()</span><span class="python_operator">, </span><span class="python_name">out_buffer </span><span class="python_operator">= </span><span class="python_name">buf</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_comment"># execute the subrequest
</span><span class="python_name">ret </span><span class="python_operator">= </span><span class="python_name">subreq</span><span class="python_operator">.</span><span class="python_name">execute</span><span class="python_enclosure">()</span><span class="python_operator">
</span>
<span class="python_comment"># perform a meaningless filter operation on the content
</span><span class="python_name">content </span><span class="python_operator">= </span><span class="python_name">re</span><span class="python_operator">.</span><span class="python_name">sub</span><span class="python_enclosure">(</span><span class="python_literal">r'foo'</span><span class="python_operator">, </span><span class="python_literal">r'bar'</span><span class="python_operator">, </span><span class="python_name">buf</span><span class="python_operator">.</span><span class="python_name">getvalue</span><span class="python_enclosure">()) </span><span class="python_operator">
</span>
<span class="python_comment"># write the content
</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">write</span><span class="python_enclosure">(</span><span class="python_name">content</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p>This component might be configured as:</p>
<div class="code">
<pre><span class="python_name">module_components </span><span class="python_operator">= </span><span class="python_enclosure">[{</span><span class="python_literal">r'/sitedocs/john/.*\.myt'</span><span class="python_operator">, </span><span class="python_literal">'mymodule:filter'</span><span class="python_enclosure">}]</span><span class="python_operator"></span></pre></div>
<p>Filtering is also built in to Myghty via the use of <%filter> section, described in <a href="filtering.html#filtering" >Filtering and Flushing (and Escaping)</a>.
</p>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
<A name="modulecomponents_templates"></a>
<div class="subsection" style="margin-left:20px;">
<span class="sectionheadertext">Using Module Components within Templates</span>
<div class="sectiontext">
<p>MCs can also be called from within templates. If an MC is configured to be callable against a URI using <span class="codeline">module_components</span> or <span class="codeline">module_root</span>, that URI can also be used within a regular <& &>-style component call. Or, the MODULE: prefix style described previously can be used.</p>
</div>
<A name="modulecomponents_templates_formexample"></a>
<div class="subsection" style="margin-left:30px;">
<span class="sectionheadertext">Example: Form Visitor</span>
<div class="sectiontext">
<p>Here is an example of a module component that is used to generate HTML forms from a data object, using the visitor pattern. Such an architecture can be used to have form information stored in a database or XML file which can then be used to automatically construct a corresponding form. This example is included in working form with the Myghty distribution.
</p>
<p><b>Step 1: Data Model</b> - The data model consists of a hierarchy of <span class="codeline">FormElement</span> objects. Some <span class="codeline">FormElement</span> objects can contain collections of other <span class="codeline">FormElements</span> (the "composite" pattern):</p>
<div class="code">
<div class="codetitle">form.py</div>
<pre><span class="python_keyword">class </span><span class="python_name">FormElement</span><span class="python_enclosure">(</span><span class="python_name">object</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">""" abstract FormElement superclass."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_keyword">pass</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">visitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""subclasses override accept_visitor to provide
the appropriate type-based visitor method."""</span><span class="python_operator">
</span><span class="python_keyword">pass</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">Form</span><span class="python_enclosure">(</span><span class="python_name">FormElement</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""represents a <FORM> tag."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">name</span><span class="python_operator">, </span><span class="python_name">action</span><span class="python_operator">, </span><span class="python_name">elements</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">name </span><span class="python_operator">= </span><span class="python_name">name</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">action </span><span class="python_operator">= </span><span class="python_name">action</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">elements </span><span class="python_operator">= </span><span class="python_name">elements</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">visitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">visitor</span><span class="python_operator">.</span><span class="python_name">visit_form</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">Field</span><span class="python_enclosure">(</span><span class="python_name">FormElement</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""abstract base class for individual user-entry fields, each
having a name, a description, and an optional value."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">name</span><span class="python_operator">, </span><span class="python_name">description</span><span class="python_operator">, </span><span class="python_name">value </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">name </span><span class="python_operator">= </span><span class="python_name">name</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">description </span><span class="python_operator">= </span><span class="python_name">description</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">value </span><span class="python_operator">= </span><span class="python_name">value</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">TextField</span><span class="python_enclosure">(</span><span class="python_name">Field</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""an <INPUT TYPE="text"> field."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">name</span><span class="python_operator">, </span><span class="python_name">description</span><span class="python_operator">, </span><span class="python_name">size</span><span class="python_operator">, </span><span class="python_name">value </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">Field</span><span class="python_operator">.</span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">name</span><span class="python_operator">, </span><span class="python_name">description</span><span class="python_operator">, </span><span class="python_name">value</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">size </span><span class="python_operator">= </span><span class="python_name">size</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">visitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">visitor</span><span class="python_operator">.</span><span class="python_name">visit_textfield</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">SelectField</span><span class="python_enclosure">(</span><span class="python_name">Field</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""a <SELECT></SELECT> tag."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">name</span><span class="python_operator">, </span><span class="python_name">description</span><span class="python_operator">, </span><span class="python_name">options</span><span class="python_operator">, </span><span class="python_name">value </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">Field</span><span class="python_operator">.</span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">name</span><span class="python_operator">, </span><span class="python_name">description</span><span class="python_operator">, </span><span class="python_name">value</span><span class="python_enclosure">)</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">options </span><span class="python_operator">= </span><span class="python_name">options</span><span class="python_operator">
</span><span class="python_keyword">for </span><span class="python_name">o </span><span class="python_keyword">in </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">options</span><span class="python_operator">:
</span><span class="python_name">o</span><span class="python_operator">.</span><span class="python_name">parent </span><span class="python_operator">= </span><span class="python_name">self</span><span class="python_operator">
</span><span class="python_keyword">if </span><span class="python_name">o</span><span class="python_operator">.</span><span class="python_name">id </span><span class="python_operator">== </span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">value</span><span class="python_operator">:
</span><span class="python_name">o</span><span class="python_operator">.</span><span class="python_name">selected </span><span class="python_operator">= </span><span class="python_name">True</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">visitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">visitor</span><span class="python_operator">.</span><span class="python_name">visit_selectfield</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">OptionField</span><span class="python_enclosure">(</span><span class="python_name">FormElement</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""an <OPTION></OPTION> tag.
contains a parent attribute that points to a <SELECT> field."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">id</span><span class="python_operator">, </span><span class="python_name">description</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">id </span><span class="python_operator">= </span><span class="python_name">id</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">description </span><span class="python_operator">= </span><span class="python_name">description</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">parent </span><span class="python_operator">= </span><span class="python_name">None</span><span class="python_operator">
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">selected </span><span class="python_operator">= </span><span class="python_name">False</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">visitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">visitor</span><span class="python_operator">.</span><span class="python_name">visit_option</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">SubmitField</span><span class="python_enclosure">(</span><span class="python_name">FormElement</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_literal">"""an <INPUT TYPE="submit"> field."""</span><span class="python_operator">
</span>
<span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">value</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">value </span><span class="python_operator">= </span><span class="python_name">value</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">visitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">visitor</span><span class="python_operator">.</span><span class="python_name">visit_submit</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p><b>Step 2: Visitor Interface</b> - This class provides the layout of a visitor object:</p>
<div class="code">
<div class="codetitle">form.py</div>
<pre><span class="python_keyword">class </span><span class="python_name">FormVisitor</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">visit_form</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">form</span><span class="python_enclosure">)</span><span class="python_operator">:</span><span class="python_keyword">pass</span><span class="python_operator">
</span><span class="python_keyword">def </span><span class="python_name">visit_textfield</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">textfield</span><span class="python_enclosure">)</span><span class="python_operator">:</span><span class="python_keyword">pass</span><span class="python_operator">
</span><span class="python_keyword">def </span><span class="python_name">visit_selectfield</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">selectfield</span><span class="python_enclosure">)</span><span class="python_operator">:</span><span class="python_keyword">pass</span><span class="python_operator">
</span><span class="python_keyword">def </span><span class="python_name">visit_option</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">option</span><span class="python_enclosure">)</span><span class="python_operator">:</span><span class="python_keyword">pass</span><span class="python_operator">
</span><span class="python_keyword">def </span><span class="python_name">visit_submit</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">submit</span><span class="python_enclosure">)</span><span class="python_operator">:</span><span class="python_keyword">pass</span><span class="python_operator"></span></pre></div>
<p><b>Step 3: HTML Rendering Components</b> - a set of Myghty methods that will render the HTML of each form element:
</p>
<div class="code">
<div class="codetitle">formfields.myc</div>
<pre><span class="doctag"><%doc></span><span class="doctag_text">
each method renders one particular HTML form element,
as well as <table> tags to provide basic layout for each.
the "form" and "select" methods are component calls with content,
to render the form elements within them.
</span><span class="doctag"></%doc></span><span class="text">
</span><span class="deftag"><%method</span><span class="compname"> form</span><span class="deftag">></span><span class="text">
</span><span class="argstag"><%args></span><span class="python_name">form</span><span class="python_operator"></span><span class="argstag"></%args></span><span class="text">
<FORM name="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">name</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">" method="POST" action="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">action</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">">
<table>
</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">content</span><span class="python_enclosure">()</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">
</table>
</FORM>
</span><span class="deftag"></%method></span><span class="text">
</span><span class="deftag"><%method</span><span class="compname"> textfield</span><span class="deftag">></span><span class="text">
</span><span class="argstag"><%args></span><span class="python_name">textfield</span><span class="python_operator"></span><span class="argstag"></%args></span><span class="text">
<tr>
<td></span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">textfield</span><span class="python_operator">.</span><span class="python_name">description</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">:</td>
<td>
<input type="text" name="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">textfield</span><span class="python_operator">.</span><span class="python_name">name</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">" value="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">textfield</span><span class="python_operator">.</span><span class="python_name">value</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">" size="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">textfield</span><span class="python_operator">.</span><span class="python_name">size</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">" >
</td>
</tr>
</span><span class="deftag"></%method></span><span class="text">
</span><span class="deftag"><%method</span><span class="compname"> submit</span><span class="deftag">></span><span class="text">
</span><span class="argstag"><%args></span><span class="python_name">submit</span><span class="python_operator"></span><span class="argstag"></%args></span><span class="text">
<tr><td colspan="2">
<input type="submit" value="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">submit</span><span class="python_operator">.</span><span class="python_name">value</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">">
</td></tr>
</span><span class="deftag"></%method></span><span class="text">
</span><span class="deftag"><%method</span><span class="compname"> select</span><span class="deftag">></span><span class="text">
</span><span class="argstag"><%args></span><span class="python_name">select</span><span class="python_operator"></span><span class="argstag"></%args></span><span class="text">
<tr>
<td></span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">select</span><span class="python_operator">.</span><span class="python_name">description</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text"></td>
<td>
<select name="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">select</span><span class="python_operator">.</span><span class="python_name">name</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">">
</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">content</span><span class="python_enclosure">()</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">
</select>
</td>
</tr>
</span><span class="deftag"></%method></span><span class="text">
</span><span class="deftag"><%method</span><span class="compname"> option</span><span class="deftag">></span><span class="text">
</span><span class="argstag"><%args></span><span class="python_name">option</span><span class="python_operator"></span><span class="argstag"></%args></span><span class="text">
<option value="</span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">option</span><span class="python_operator">.</span><span class="python_name">id</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">" </span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">option</span><span class="python_operator">.</span><span class="python_name">selected </span><span class="python_keyword">and </span><span class="python_literal">"SELECTED" </span><span class="python_keyword">or </span><span class="python_literal">""</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text">></span><span class="substitution"><%</span><span class="python_operator"> </span><span class="python_name">option</span><span class="python_operator">.</span><span class="python_name">description</span><span class="python_operator"> </span><span class="substitution">%></span><span class="text"></option>
</span><span class="deftag"></%method></span></pre></div>
<p><b>Step 4: Module Component</b> - ties it all together. The FormGenerator serves as the traversal unit for the Form object, as well as the visitor implementation itself. The visit_form and visit_selectfield methods both involve contained formelements, and the corresponding myghty components are component calls with content; so for those, a content function is created to handle the embedded content.
</p>
<div class="code">
<div class="codetitle">form.py</div>
<pre><span class="python_keyword">def </span><span class="python_name">renderform</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_operator">, </span><span class="python_name">form</span><span class="python_operator">, **</span><span class="python_name">params</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">FormGenerator</span><span class="python_operator">.</span><span class="python_name">RenderForm</span><span class="python_enclosure">(</span><span class="python_name">m</span><span class="python_enclosure">))</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">class </span><span class="python_name">RenderForm</span><span class="python_enclosure">(</span><span class="python_name">FormVisitor</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">__init__</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">m</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">m </span><span class="python_operator">= </span><span class="python_name">m</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">visit_form</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">form</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">formcontent</span><span class="python_enclosure">()</span><span class="python_operator">:
</span><span class="python_keyword">for </span><span class="python_name">element </span><span class="python_keyword">in </span><span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">elements</span><span class="python_operator">:
</span><span class="python_name">element</span><span class="python_operator">.</span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">execute_component</span><span class="python_enclosure">(</span><span class="python_literal">"formfields.myc:form"</span><span class="python_operator">, </span><span class="python_name">args </span><span class="python_operator">= </span><span class="python_name">dict</span><span class="python_enclosure">(</span><span class="python_name">form </span><span class="python_operator">= </span><span class="python_name">form</span><span class="python_enclosure">)</span><span class="python_operator">, </span><span class="python_name">content</span><span class="python_operator">=</span><span class="python_name">formcontent</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">visit_textfield</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">textfield</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">comp</span><span class="python_enclosure">(</span><span class="python_literal">"formfields.myc:textfield"</span><span class="python_operator">, </span><span class="python_name">textfield </span><span class="python_operator">= </span><span class="python_name">textfield</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">visit_selectfield</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">selectfield</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_keyword">def </span><span class="python_name">selectcontent</span><span class="python_enclosure">()</span><span class="python_operator">:
</span><span class="python_keyword">for </span><span class="python_name">element </span><span class="python_keyword">in </span><span class="python_name">selectfield</span><span class="python_operator">.</span><span class="python_name">options</span><span class="python_operator">:
</span><span class="python_name">element</span><span class="python_operator">.</span><span class="python_name">accept_visitor</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">execute_component</span><span class="python_enclosure">(</span><span class="python_literal">"formfields.myc:select"</span><span class="python_operator">, </span><span class="python_name">args </span><span class="python_operator">= </span><span class="python_name">dict</span><span class="python_enclosure">(</span><span class="python_name">select </span><span class="python_operator">= </span><span class="python_name">selectfield</span><span class="python_enclosure">)</span><span class="python_operator">, </span><span class="python_name">content</span><span class="python_operator">=</span><span class="python_name">selectcontent</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">visit_option</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">option</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">comp</span><span class="python_enclosure">(</span><span class="python_literal">"formfields.myc:option"</span><span class="python_operator">, </span><span class="python_name">option </span><span class="python_operator">= </span><span class="python_name">option</span><span class="python_enclosure">)</span><span class="python_operator">
</span>
<span class="python_operator"></span><span class="python_keyword">def </span><span class="python_name">visit_submit</span><span class="python_enclosure">(</span><span class="python_name">self</span><span class="python_operator">, </span><span class="python_name">submit</span><span class="python_enclosure">)</span><span class="python_operator">:
</span><span class="python_name">self</span><span class="python_operator">.</span><span class="python_name">m</span><span class="python_operator">.</span><span class="python_name">comp</span><span class="python_enclosure">(</span><span class="python_literal">"formfields.myc:submit"</span><span class="python_operator">, </span><span class="python_name">submit </span><span class="python_operator">= </span><span class="python_name">submit</span><span class="python_enclosure">)</span><span class="python_operator"></span></pre></div>
<p><b>Step 5: Fire it Up</b> - this myghty template actually calls the <span class="codeline">renderform</span> Module Component.
</p>
<div class="code">
<div class="codetitle">registration.myt</div>
<pre><span class="doctag"><%doc></span><span class="doctag_text">
an example firstname/lastname/occupation registration form.
</span><span class="doctag"></%doc></span><span class="text">
</span><span class="blocktag"><%python></span>
<span class="python_operator"> </span><span class="python_keyword">import </span><span class="python_name">form</span><span class="python_operator">
</span><span class="python_name">registerform </span><span class="python_operator">= </span><span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">Form</span><span class="python_enclosure">(</span><span class="python_literal">'myform'</span><span class="python_operator">, </span><span class="python_literal">'register.myt'</span><span class="python_operator">, </span><span class="python_name">elements </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">TextField</span><span class="python_enclosure">(</span><span class="python_literal">'firstname'</span><span class="python_operator">, </span><span class="python_literal">'First Name'</span><span class="python_operator">, </span><span class="python_name">size</span><span class="python_operator">=</span><span class="python_number">50</span><span class="python_enclosure">)</span><span class="python_operator">,</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">TextField</span><span class="python_enclosure">(</span><span class="python_literal">'lastname'</span><span class="python_operator">, </span><span class="python_literal">'Last Name'</span><span class="python_operator">, </span><span class="python_name">size</span><span class="python_operator">=</span><span class="python_number">50</span><span class="python_enclosure">)</span><span class="python_operator">,</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">SelectField</span><span class="python_enclosure">(</span><span class="python_literal">'occupation'</span><span class="python_operator">, </span><span class="python_literal">'Occupation'</span><span class="python_operator">, </span>
<span class="python_name">options </span><span class="python_operator">= </span><span class="python_enclosure">[</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">OptionField</span><span class="python_enclosure">(</span><span class="python_literal">'skydiver'</span><span class="python_operator">, </span><span class="python_literal">'Sky Diver'</span><span class="python_enclosure">)</span><span class="python_operator">,</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">OptionField</span><span class="python_enclosure">(</span><span class="python_literal">'programmer'</span><span class="python_operator">, </span><span class="python_literal">'Computer Programmer'</span><span class="python_enclosure">)</span><span class="python_operator">,</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">OptionField</span><span class="python_enclosure">(</span><span class="python_literal">''</span><span class="python_operator">, </span><span class="python_literal">'No Answer'</span><span class="python_enclosure">)</span><span class="python_operator">,</span>
<span class="python_enclosure">]</span>
<span class="python_enclosure">)</span><span class="python_operator">,</span>
<span class="python_name">form</span><span class="python_operator">.</span><span class="python_name">SubmitField</span><span class="python_enclosure">(</span><span class="python_literal">'register'</span><span class="python_enclosure">)</span>
<span class="python_enclosure">]</span>
<span class="python_enclosure">)</span><span class="python_operator">
</span><span class="blocktag"></%python></span><span class="text">
Welcome to the Skydivers or Computer Programmers Club !
</span><span class="compcall"><& </span><span class="compname">MODULE:form:renderform</span><span class="python_operator">, </span><span class="python_name">form </span><span class="python_operator">= </span><span class="python_name">registerform</span><span class="python_operator"> </span><span class="compcall">&></span></pre></div>
</div>
<a href="#modulecomponents" class="toclink">back to section top</a>
</div>
</div>
<div class="sectionnavblock">
<div class="sectionnav">
Previous: <a href="components.html">Components</a>
|
Next: <a href="request.html">The Request</a>
</div>
</div>
</div>
</div>
</div>
<center>
</center>
</body>
</html>
|