lv2-dev 1.8.0~dfsg0-1 / usr / lib / lv2 / patch.lv2 / patch.ttl

@prefix foaf:  <http://xmlns.com/foaf/0.1/> .
@prefix lv2:   <http://lv2plug.in/ns/lv2core#> .
@prefix owl:   <http://www.w3.org/2002/07/owl#> .
@prefix patch: <http://lv2plug.in/ns/ext/patch#> .
@prefix rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs:  <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd:   <http://www.w3.org/2001/XMLSchema#> .

<http://lv2plug.in/ns/ext/patch>
	a owl:Ontology ;
	rdfs:seeAlso <patch.h> ,
		<lv2-patch.doap.ttl> ;
	lv2:documentation """
<p>This vocabulary defines messages which can be used to access and manipulate
properties.  It is designed to provide a dynamic control interface for LV2
plugins, but is useful in many contexts.</p>

<p>The main feature of this design is that the messages themselves are
described in the same format as the data they work with.  In particular,
messages can be serialised as a binary <a
href="../atom/atom.html#Object">Object</a> or in Turtle (or any other RDF
serialisation).</p>

<p>The idea behind using a property-based interface for control is to prevent
an an explosion of message types.  Instead of a custom message for each action,
control is achieved via manipulating properties (which are likely already
defined for other reasons).  Note, however, that this is purely conceptual;
there is no requirement that the receiver actually implement a store of
resources with properties.</p>

<p>For example, consider an object that can blink.  Rather than define a
specific interface to control this (e.g. <code>obj.start_blinking();
obj.stop_blinking()</code>), set a <q>blinking</q> property to true or false
(e.g. <code>obj.set(blinking, true)</code>) to achieve the desired behaviour.
One benefit of this approach is that a persistent state model is available
<q>for free</q>: simply serialise the <q>blinking</q> property.</p>

<p>This specification is strictly metadata and does not define any binary
mechanism, though it can be completely expressed by standard types in the <a
href="../atom/atom.html">LV2 Atom</a> extension.  Thus, hosts can be expected
to be capable of transmitting it between plugins, or between a plugin and its
UI, making it a good choice for advanced plugin control.</p>
""" .

patch:Ack
	a rdfs:Class ;
	rdfs:subClassOf patch:Response ;
	rdfs:label "Ack" ;
	lv2:documentation """
<p>An acknowledgement that a request has been successfully processed.  This is
returned as a reply when a specific reply type is not necessary or
appropriate.</p>
""" .

patch:Delete
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ;
	rdfs:label "Delete" ;
	lv2:documentation """
<p>Request the subject(s) be deleted.</p>
""" .

patch:Error
	a rdfs:Class ;
	rdfs:subClassOf patch:Response ;
	rdfs:label "Error" ;
	lv2:documentation """
<p>A response indicating an error processing a request.</p>
""" .

patch:Get
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ;
	rdfs:label "Get" ;
	lv2:documentation """
<p>Request a description of the subject.</p>

<p>The detail of the response is not specified, it may be a flat description of
all the properties of the subject, or a more expressive description with
several subjects.  A good choice is a <q><a
href="http://www.w3.org/Submission/CBD/">concise bounded description</a></q>,
i.e. a description which recursively includes all properties with blank node
values.</p>

<p>The response should have the same patch:subject property as the request, and
a patch:body that is a description of that subject.  For example:</p>
<pre class="turtle-code">
&lt;get-request&gt;
    a patch:Get ;
    patch:subject &lt;something&gt; .
</pre>

<p>Could result in:</p>
<pre class="turtle-code">
[]
    a patch:Response ;
    patch:request &lt;get-request&gt; ;
    patch:subject &lt;something&gt; ;
    patch:body [
        eg:name "Something" ;
        eg:ratio 1.6180339887 ;
    ] .
</pre>

<p>Note the use of blank nodes is not required; the value of patch:body may be
the actual resource node.  Depending on the transport and syntax used this may
be preferable.  However, the patch:subject property is required regardless.  For
example, the same response could be written:</p>

<pre class="turtle-code">
&lt;something&gt;
    eg:name "Something" ;
    eg:ratio 1.6180339887 .

[]
    a patch:Response ;
    patch:request &lt;get-request&gt; ;
    patch:subject &lt;something&gt; ;
    patch:body &lt;something&gt; .
</pre>
""" .

patch:Insert
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ;
	rdfs:label "Insert" ;
	rdfs:subClassOf [
		a owl:Restriction ;
		owl:cardinality 1 ;
		owl:onProperty patch:subject
	] ;
	lv2:documentation """
<p>Insert the patch:body at patch:subject.  If the subject does not exist, it is
created.  If the subject does already exist, it is added to.  This request only
adds properties, it never removes them.  The user must take care that multiple
values are not set for properties which should only have one value.</p>
""" .

patch:Message
	a rdfs:Class ;
	rdfs:label "Message" .

patch:Move
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ;
	rdfs:label "Move" ;
	rdfs:subClassOf [
		a owl:Restriction ;
		owl:cardinality 1 ;
		owl:onProperty patch:subject
	] , [
		a owl:Restriction ;
		owl:cardinality 1 ;
		owl:onProperty patch:destination
	] ;
	lv2:documentation """
<p>Move the patch:subject to patch:destination.  After this, patch:destination has
the description patch:subject had prior to this request's execution, and
patch:subject does not exist any more.It is an error if the subject does not
exist or the destination already exists.</p>
""" .

patch:Patch
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ,
	[
		a owl:Restriction ;
		owl:minCardinality 1 ;
		owl:onProperty patch:subject
	] ;
	lv2:documentation """
<p>A method for modifying the properties of an object.</p>

<p>This method always has at least one patch:subject, and exactly one patch:add
and patch:remove property.  The value of patch:add and patch:remove are nodes
which have the properties to add or remove from the subject(s), respectively.
The special value patch:wildcard may be used as the value of a remove property
to remove all properties with the given predicate.  For example:</p>

<pre class="turtle-code">
[]
    a patch:Patch ;
    patch:subject &lt;something&gt; ;
    patch:add [
        eg:name "New name" ;
        eg:age 42 ;
    ] ;
    patch:remove [
        eg:name "Old name" ;
        eg:age patch:wildcard ;  # Remove all old eg:age properties
    ] .
</pre>
""" .

patch:Put
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ;
	rdfs:label "Put" ;
	rdfs:subClassOf [
		a owl:Restriction ;
		owl:cardinality 1 ;
		owl:onProperty patch:subject
	] ;
	lv2:documentation """
<p>Put the patch:body as the patch:subject.  If the subject does not already exist,
it is created.  If the subject does already exist, the patch:body is considered
an updated version of it, and the previous version is replaced.</p>
""" .

patch:Request
	a rdfs:Class ;
	rdfs:label "Request" ;
	rdfs:subClassOf patch:Message ;
	lv2:documentation """
<p>A request.  A request may have a patch:subject property, which indicates which
resource the request applies to.  The subject may be omitted in contexts where
it is implicit (e.g. the recipient is the subject).</p>
""" .

patch:Response
	a rdfs:Class ;
	rdfs:subClassOf patch:Message ;
	rdfs:label "Response" ;
	lv2:documentation """
<p>A response to a method.</p>
""" .

patch:Set
	a rdfs:Class ;
	rdfs:subClassOf patch:Request ,
	[
		a owl:Restriction ;
		owl:cardinality 1 ;
		owl:onProperty patch:property
	] , [
		a owl:Restriction ;
		owl:cardinality 1 ;
		owl:onProperty patch:value
	] ;
	lv2:documentation """
<p>A compact message for setting one property to a specific value.</p>

<p>This is equivalent to a patch:Patch which removes <em>all</em> pre-existing
values for the property before setting the new value.  For example:</p>

<pre class="turtle-code">
[]
    a patch:Set ;
    patch:subject &lt;something&gt; ;
    patch:property eg:name ;
    patch:value "New name" .
</pre>

<p>Which is equivalent to:</p>
<pre class="turtle-code">
[]
    a patch:Patch ;
    patch:subject &lt;something&gt; ;
    patch:add [
        eg:name "New name" ;
    ] ;
    patch:remove [
        eg:name patch:wildcard ;
    ] .
</pre>
""" .

patch:add
	a rdf:Property ,
		owl:ObjectProperty ,
		owl:FunctionalProperty ;
	rdfs:domain patch:Message .

patch:body
	a rdf:Property ,
		owl:ObjectProperty ,
		owl:FunctionalProperty ;
	rdfs:domain patch:Message ;
	lv2:documentation """
<p>The body of a message.</p>

<p>The details of this property's value depend on the type of message it is a
part of.</p>
""" .

patch:destination
	a rdf:Property ,
		owl:ObjectProperty ,
		owl:FunctionalProperty ;
	rdfs:domain patch:Message .

patch:property
	a rdf:Property ;
	rdfs:label "property" ;
	rdfs:range rdf:Property ;
	lv2:documentation """
<p>The property this message applies to.</p>
""" .

patch:readable
	a rdf:Property ;
	rdfs:label "readable" ;
	rdfs:range rdf:Property ;
	lv2:documentation """
<p>Indicates that the subject may have a property that can be read via a
patch:Get message.  See the similar property patch:writable for details.</p>
""" .

patch:remove
	a rdf:Property ,
		owl:ObjectProperty ,
		owl:FunctionalProperty ;
	rdfs:domain patch:Message .

patch:request
	a rdf:Property ,
		owl:ObjectProperty ,
		owl:FunctionalProperty ;
	rdfs:domain patch:Response ;
	rdfs:range patch:Request ;
	lv2:documentation """
<p>The request this is a response to.</p>
""" .

patch:subject
	a rdf:Property ,
		owl:ObjectProperty ,
		owl:FunctionalProperty ;
	rdfs:domain patch:Message .

patch:value
	a rdf:Property ;
	rdfs:label "value" ;
	rdfs:range rdf:Property ;
	lv2:documentation """
<p>The value of a property in a patch:Set message.</p>
""" .

patch:wildcard
	a rdfs:Resource ;
	rdfs:comment """
A wildcard which matches any resource.  This makes it possible to describe the removal of all values for a given property.
""" .

patch:writable
	a rdf:Property ;
	rdfs:label "writable" ;
	rdfs:range rdf:Property ;
	lv2:documentation """
<p>Indicates that subject may have a property that can be written via a patch
message.  This is used to list supported properties, e.g. so user interfaces
can present appropriate controls.  For example:</p>

<pre class="turtle-code">
@prefix eg:   &lt;http://example.org/&gt; .
@prefix rdf:  &lt;http://www.w3.org/1999/02/22-rdf-syntax-ns#&gt; .
@prefix rdfs: &lt;http://www.w3.org/2000/01/rdf-schema#&gt; .

eg:title
    a rdf:Property ;
    rdfs:label "title" ;
    rdfs:range xsd:string .

eg:plugin
    patch:writable eg:title .
</pre>
""" .