Viewing file:  util.py (5.66 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
# -*- test-case-name: twisted.test.test_enterprise -*-
# Copyright (c) 2001-2008 Twisted Matrix Laboratories.
# See LICENSE for details.
import warnings, types
from twisted.python.versions import Version, getVersionString
from twisted.python.deprecate import deprecated
from twisted.enterprise.adbapi import _safe
# Common deprecation decorator used for all deprecations.
_deprecatedVersion = Version("Twisted", 8, 0, 0)
_releasedDeprecation = deprecated(_deprecatedVersion)
warnings.warn(
"twisted.enterprise.util is deprecated since %s." % (
getVersionString(_deprecatedVersion),),
category=DeprecationWarning)
NOQUOTE = 1
USEQUOTE = 2
dbTypeMap = {
"bigint": NOQUOTE,
"bool": USEQUOTE,
"boolean": USEQUOTE,
"bytea": USEQUOTE,
"date": USEQUOTE,
"int2": NOQUOTE,
"int4": NOQUOTE,
"int8": NOQUOTE,
"int": NOQUOTE,
"integer": NOQUOTE,
"float4": NOQUOTE,
"float8": NOQUOTE,
"numeric": NOQUOTE,
"real": NOQUOTE,
"smallint": NOQUOTE,
"char": USEQUOTE,
"text": USEQUOTE,
"time": USEQUOTE,
"timestamp": USEQUOTE,
"varchar": USEQUOTE
}
class DBError(Exception):
pass
### Utility functions
def getKeyColumn(rowClass, name):
lcname = name.lower()
for keyColumn, type in rowClass.rowKeyColumns:
if lcname == keyColumn.lower():
return name
return None
getKeyColumn = _releasedDeprecation(getKeyColumn)
def quote(value, typeCode, string_escaper=_safe):
"""Add quotes for text types and no quotes for integer types.
NOTE: uses Postgresql type codes.
"""
q = dbTypeMap.get(typeCode, None)
if q is None:
raise DBError("Type %s not known" % typeCode)
if value is None:
return 'null'
if q == NOQUOTE:
return str(value)
elif q == USEQUOTE:
if typeCode.startswith('bool'):
if value:
value = '1'
else:
value = '0'
if typeCode == "bytea":
l = ["'"]
for c in value:
i = ord(c)
if i == 0:
l.append("\\\\000")
elif i == 92:
l.append(c * 4)
elif 32 <= i <= 126:
l.append(c)
else:
l.append("\\%03o" % i)
l.append("'")
return "".join(l)
if not isinstance(value, types.StringType) and \
not isinstance(value, types.UnicodeType):
value = str(value)
return "'%s'" % string_escaper(value)
quote = _releasedDeprecation(quote)
def safe(text):
"""
Make a string safe to include in an SQL statement.
"""
return _safe(text)
safe = _releasedDeprecation(safe)
def makeKW(rowClass, args):
"""Utility method to construct a dictionary for the attributes
of an object from set of args. This also fixes the case of column names.
"""
kw = {}
for i in range(0,len(args)):
columnName = rowClass.dbColumns[i][0].lower()
for attr in rowClass.rowColumns:
if attr.lower() == columnName:
kw[attr] = args[i]
break
return kw
makeKW = _releasedDeprecation(makeKW)
def defaultFactoryMethod(rowClass, data, kw):
"""Used by loadObjects to create rowObject instances.
"""
newObject = rowClass()
newObject.__dict__.update(kw)
return newObject
defaultFactoryMethod = _releasedDeprecation(defaultFactoryMethod)
### utility classes
class _TableInfo:
"""(internal)
Info about a table/class and it's relationships. Also serves as a container for
generated SQL.
"""
def __init__(self, rc):
self.rowClass = rc
self.rowTableName = rc.rowTableName
self.rowKeyColumns = rc.rowKeyColumns
self.rowColumns = rc.rowColumns
if hasattr(rc, "rowForeignKeys"):
self.rowForeignKeys = rc.rowForeignKeys
else:
self.rowForeignKeys = []
if hasattr(rc, "rowFactoryMethod"):
if rc.rowFactoryMethod:
self.rowFactoryMethod = rc.rowFactoryMethod
else:
self.rowFactoryMethod = [defaultFactoryMethod]
else:
self.rowFactoryMethod = [defaultFactoryMethod]
self.updateSQL = None
self.deleteSQL = None
self.insertSQL = None
self.relationships = []
self.dbColumns = []
def addForeignKey(self, childColumns, parentColumns, childRowClass, containerMethod, autoLoad):
"""This information is attached to the "parent" table
childColumns - columns of the "child" table
parentColumns - columns of the "parent" table, the one being joined to... the "foreign" table
"""
self.relationships.append( _TableRelationship(childColumns, parentColumns,
childRowClass, containerMethod, autoLoad) )
def getRelationshipFor(self, tableName):
for relationship in self.relationships:
if relationship.childRowClass.rowTableName == tableName:
return relationship
return None
class _TableRelationship:
"""(Internal)
A foreign key relationship between two tables.
"""
def __init__(self,
childColumns,
parentColumns,
childRowClass,
containerMethod,
autoLoad):
self.childColumns = childColumns
self.parentColumns = parentColumns
self.childRowClass = childRowClass
self.containerMethod = containerMethod
self.autoLoad = autoLoad
__all__ = ['NOQUOTE', 'USEQUOTE', 'dbTypeMap', 'DBError', 'getKeyColumn',
'safe', 'quote']
|