/usr/lib/python2.7/dist-packages/stetl/outputs/dboutput.py is in python-stetl 1.1+ds-2.
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 | # -*- coding: utf-8 -*-
#
# Output classes for ETL, databases.
#
# Author: Just van den Broecke
#
from stetl.output import Output
from stetl.util import Util
from stetl.packet import FORMAT
from stetl.component import Config
from stetl.postgis import PostGIS
log = Util.get_log('dboutput')
class DbOutput(Output):
"""
Output to any database (abstract base class).
"""
def __init__(self, configdict, section, consumes):
Output.__init__(self, configdict, section, consumes)
def write(self, packet):
return packet
class PostgresDbOutput(DbOutput):
"""
Output to PostgreSQL database.
Input is an SQL string.
Output by executing input SQL string.
consumes=FORMAT.string
"""
# Start attribute config meta
@Config(ptype=str, required=True, default=None)
def database(self):
"""
Database name.
"""
pass
@Config(ptype=str, required=False, default=None)
def user(self):
"""
DB User name.
"""
pass
@Config(ptype=str, required=False, default=None)
def password(self):
"""
DB Password for user.
"""
pass
@Config(ptype=str, required=False, default=None)
def host(self):
"""
Hostname for DB.
"""
pass
@Config(ptype=str, required=False, default='public')
def schema(self):
"""
Postgres schema name for DB.
"""
pass
# End attribute config meta
def __init__(self, configdict, section):
DbOutput.__init__(self, configdict, section, consumes=FORMAT.string)
def write(self, packet):
if packet.data is None:
return packet
log.info('executing SQL')
db = PostGIS(self.cfg.get_dict())
rowcount = db.tx_execute(packet.data)
log.info('executed SQL, rowcount=%d' % rowcount)
return packet
class PostgresInsertOutput(PostgresDbOutput):
"""
Output by inserting single record into Postgres database.
Input is a record (Python dic structure) or a Python list of dicts (records).
Creates an INSERT for Postgres to insert each single record.
When the "replace" parameter is True, any existing record keyed by "key" is
attempted to be deleted first.
NB a constraint is that each record needs to contain all values as
an INSERT query is built once for the columns in the first record.
consumes=FORMAT.record
"""
# Start attribute config meta
@Config(ptype=str, required=False, default='public')
def table(self):
"""
Table for inserts.
"""
pass
@Config(ptype=bool, required=False, default=False)
def replace(self):
"""
Replace record if exists?
"""
pass
@Config(ptype=str, required=False, default=None)
def key(self):
"""
The key column name of the table, required when replacing records.
"""
pass
# End attribute config meta
def __init__(self, configdict, section, consumes=FORMAT.record):
DbOutput.__init__(self, configdict, section, consumes=[FORMAT.record_array, FORMAT.record])
self.query = None
self.db = None
def init(self):
# Connect only once to DB
log.info('Init: connect to DB')
self.db = PostGIS(self.cfg.get_dict())
self.db.connect()
def exit(self):
# Disconnect from DB when done
log.info('Exit: disconnect from DB')
self.db.disconnect()
def create_query(self, record):
# We assume that all records do the same INSERT key/values
# See http://grokbase.com/t/postgresql/psycopg/12735bvkmv/insert-into-with-a-dictionary-or-generally-with-a-variable-number-of-columns
# e.g. INSERT INTO lml_files ("file_name", "file_data") VALUES (%s,%s)
query = "INSERT INTO %s (%s) VALUES (%s)" % (
self.cfg.get('table'), ",".join(['%s' % k for k in record]), ",".join(["%s", ] * len(record.keys())))
log.info('query is %s', query)
return query
def insert(self, record):
if self.replace and self.key and self.key in record:
# Try to delete (replace option)
del_query = "DELETE FROM %s WHERE %s = '%s'" % (self.cfg.get('table'), self.key, record[self.key])
self.db.execute(del_query)
# Do insert with values from the record dict
self.db.execute(self.query, record.values())
self.db.commit(close=False)
def write(self, packet):
# Deal with empty or zero-length data structures (list or dict)
if packet.data is None or len(packet.data) == 0:
return packet
# ASSERT: record data present
# record is Python dict (single record) or list of Python dict (multiple records)
record = packet.data
# Generate INSERT query template once
first_record = record
if type(record) is list and len(record) > 0:
first_record = record[0]
# Create query once
if self.query is None:
self.query = self.create_query(first_record)
# Check if record is single (dict) or array (list of dict)
if type(record) is dict:
# Do insert with values from the single record
self.insert(record)
# log.info('committed record key=%s' % record[self.key])
elif type(record) is list:
# Multiple records in list
for rec in record:
# Do insert with values from the record
self.insert(rec)
log.info('committed %d records' % len(record))
return packet
|