sqlobject/sqlobject/main.py at master · sqlobject/sqlobject · GitHub

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"""

SQLObject

---------

:author: Ian Bicking <ianb@colorstudy.com>

SQLObject is a object-relational mapper. See SQLObject.html or

SQLObject.rst for more.

With the help by Oleg Broytman and many other contributors.

See Authors.rst.

This program is free software; you can redistribute it and/or modify

it under the terms of the GNU Lesser General Public License as

published by the Free Software Foundation; either version 2.1 of the

License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

GNU General Public License for more details.

You should have received a copy of the GNU Lesser General Public

License along with this program; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301,

USA.

"""

import sys

import threading

import weakref

import types

import warnings

from . import sqlbuilder

from . import dbconnection

from . import col

from . import styles

from . import joins

from . import index

from . import classregistry

from . import declarative

from . import events

from .sresults import SelectResults

from .util.threadinglocal import local

from sqlobject.compat import PY2, with_metaclass, string_type, unicode_type

if ((sys.version_info[0] == 2) and (sys.version_info[:2] < (2, 7))) or \

((sys.version_info[0] == 3) and (sys.version_info[:2] < (3, 4))):

raise ImportError("SQLObject requires Python 2.7 or 3.4+")

if not PY2:

# alias for python 3 compatability

long = int

"""

This thread-local storage is needed for RowCreatedSignals. It gathers

code-blocks to execute _after_ the whole hierachy of inherited SQLObjects

is created. See SQLObject._create

"""

NoDefault = sqlbuilder.NoDefault

class SQLObjectNotFound(LookupError):

pass

class SQLObjectIntegrityError(Exception):

pass

def makeProperties(obj):

"""

This function takes a dictionary of methods and finds

methods named like:

* _get_attr

* _set_attr

* _del_attr

* _doc_attr

Except for _doc_attr, these should be methods. It

then creates properties from these methods, like

property(_get_attr, _set_attr, _del_attr, _doc_attr).

Missing methods are okay.

"""

if isinstance(obj, dict):

def setFunc(var, value):

obj[var] = value

d = obj

else:

def setFunc(var, value):

setattr(obj, var, value)

d = obj.__dict__

props = {}

for var, value in d.items():

if var.startswith('_set_'):

props.setdefault(var[5:], {})['set'] = value

elif var.startswith('_get_'):

props.setdefault(var[5:], {})['get'] = value

elif var.startswith('_del_'):

props.setdefault(var[5:], {})['del'] = value

elif var.startswith('_doc_'):

props.setdefault(var[5:], {})['doc'] = value

for var, setters in props.items():

if len(setters) == 1 and 'doc' in setters:

continue

if var in d:

if isinstance(d[var], (types.MethodType, types.FunctionType)):

warnings.warn(

"I tried to set the property %r, but it was "

"already set, as a method (%r). Methods have "

"significantly different semantics than properties, "

"and this may be a sign of a bug in your code."

% (var, d[var]))

continue

setFunc(var,

property(setters.get('get'), setters.get('set'),

setters.get('del'), setters.get('doc')))

def unmakeProperties(obj):

if isinstance(obj, dict):

def delFunc(obj, var):

del obj[var]

d = obj

else:

delFunc = delattr

d = obj.__dict__

for var, value in list(d.items()):

if isinstance(value, property):

for prop in [value.fget, value.fset, value.fdel]:

if prop and prop.__name__ not in d:

delFunc(obj, var)

break

def findDependencies(name, registry=None):

depends = []

for klass in classregistry.registry(registry).allClasses():

if findDependantColumns(name, klass):

depends.append(klass)

else:

for join in klass.sqlmeta.joins:

if isinstance(join, joins.SORelatedJoin) and \

join.otherClassName == name:

depends.append(klass)

break

return depends

def findDependantColumns(name, klass):

depends = []

for _col in klass.sqlmeta.columnList:

if _col.foreignKey == name and _col.cascade is not None:

depends.append(_col)

return depends

def _collectAttributes(cls, new_attrs, look_for_class):

"""Finds all attributes in `new_attrs` that are instances of

`look_for_class`. The ``.name`` attribute is set for any matching objects.

Returns them as a list.

"""

result = []

for attr, value in new_attrs.items():

if isinstance(value, look_for_class):

value.name = attr

delattr(cls, attr)

result.append(value)

return result

class CreateNewSQLObject:

"""

Dummy singleton to use in place of an ID, to signal we want

a new object.

"""

pass

class sqlmeta(with_metaclass(declarative.DeclarativeMeta, object)):

"""

This object is the object we use to keep track of all sorts of

information. Subclasses are made for each SQLObject subclass

(dynamically if necessary), and instances are created to go

alongside every SQLObject instance.

"""

table = None

idName = None

idSize = None # Allowed values are 'TINY/SMALL/MEDIUM/BIG/None'

idSequence = None

# This function is used to coerce IDs into the proper format,

# so you should replace it with str, or another function, if you

# aren't using integer IDs

idType = int

style = None

lazyUpdate = False

defaultOrder = None

cacheValues = True

registry = None

fromDatabase = False

# Default is false, but we set it to true for the *instance*

# when necessary: (bad clever? maybe)

expired = False

# This is a mapping from column names to SOCol (or subclass)

# instances:

columns = {}

columnList = []

# This is a mapping from column names to Col (or subclass)

# instances; these objects don't have the logic that the SOCol

# objects do, and are not attached to this class closely.

columnDefinitions = {}

# These are lists of the join and index objects:

indexes = []

indexDefinitions = []

joins = []

joinDefinitions = []

# These attributes shouldn't be shared with superclasses:

_unshared_attributes = ['table', 'columns', 'childName']

# These are internal bookkeeping attributes; the class-level

# definition is a default for the instances, instances will

# reset these values.

# When an object is being created, it has an instance

# variable _creating, which is true. This way all the

# setters can be captured until the object is complete,

# and then the row is inserted into the database. Once

# that happens, _creating is deleted from the instance,

# and only the class variable (which is always false) is

# left.

_creating = False

_obsolete = False

# Sometimes an intance is attached to a connection, not

# globally available. In that case, self.sqlmeta._perConnection

# will be true. It's false by default:

_perConnection = False

# Inheritance definitions:

parentClass = None # A reference to the parent class

childClasses = {} # References to child classes, keyed by childName

childName = None # Class name for inheritance child object creation

# Does the row require syncing?

dirty = False

# Default encoding for UnicodeCol's

dbEncoding = None

def __classinit__(cls, new_attrs):

for attr in cls._unshared_attributes:

if attr not in new_attrs:

setattr(cls, attr, None)

declarative.setup_attributes(cls, new_attrs)

def __init__(self, instance):

self.instance = weakref.proxy(instance)

@classmethod

def send(cls, signal, *args, **kw):

events.send(signal, cls.soClass, *args, **kw)

@classmethod

def setClass(cls, soClass):

if cls.idType not in (int, str):

raise TypeError('sqlmeta.idType must be int or str, not %r'

% cls.idType)

if cls.idSize not in ('TINY', 'SMALL', 'MEDIUM', 'BIG', None):

raise ValueError(

"sqlmeta.idType must be 'TINY', 'SMALL', 'MEDIUM', 'BIG' "

"or None, not %r" % cls.idSize)

cls.soClass = soClass

if not cls.style:

cls.style = styles.defaultStyle

try:

if cls.soClass._connection and cls.soClass._connection.style:

cls.style = cls.soClass._connection.style

except AttributeError:

pass

if cls.table is None:

cls.table = cls.style.pythonClassToDBTable(cls.soClass.__name__)

if cls.idName is None:

cls.idName = cls.style.idForTable(cls.table)

# plainSetters are columns that haven't been overridden by the

# user, so we can contact the database directly to set them.

# Note that these can't set these in the SQLObject class

# itself, because they specific to this subclass of SQLObject,

# and cannot be shared among classes.

cls._plainSetters = {}

cls._plainGetters = {}

cls._plainForeignSetters = {}

cls._plainForeignGetters = {}

cls._plainJoinGetters = {}

cls._plainJoinAdders = {}

cls._plainJoinRemovers = {}

# This is a dictionary of columnName: columnObject

# None of these objects can be shared with superclasses

cls.columns = {}

cls.columnList = []

# These, however, can be shared:

cls.columnDefinitions = cls.columnDefinitions.copy()

cls.indexes = []

cls.indexDefinitions = cls.indexDefinitions[:]

cls.joins = []

cls.joinDefinitions = cls.joinDefinitions[:]

############################################################

# Adding special values, like columns and indexes

############################################################

########################################

# Column handling

########################################

@classmethod

def addColumn(cls, columnDef, changeSchema=False, connection=None):

post_funcs = []

cls.send(events.AddColumnSignal, cls.soClass, connection,

columnDef.name, columnDef, changeSchema, post_funcs)

sqlmeta = cls

soClass = cls.soClass

del cls

column = columnDef.withClass(soClass)

name = column.name

assert name != 'id', (

"The 'id' column is implicit, and should not be defined as "

"a column")

assert name not in sqlmeta.columns, (

"The class %s.%s already has a column %r (%r), you cannot "

"add the column %r"

% (soClass.__module__, soClass.__name__, name,

sqlmeta.columnDefinitions[name], columnDef))

# Collect columns from the parent classes to test

# if the column is not in a parent class

parent_columns = []

for base in soClass.__bases__:

if hasattr(base, "sqlmeta"):

parent_columns.extend(base.sqlmeta.columns.keys())

if hasattr(soClass, name):

assert (name in parent_columns) or (name == "childName"), (

"The class %s.%s already has a variable or method %r, "

"you cannot add the column %r" % (

soClass.__module__, soClass.__name__, name, name))

sqlmeta.columnDefinitions[name] = columnDef

sqlmeta.columns[name] = column

# A stable-ordered version of the list...

sqlmeta.columnList.append(column)

###################################################

# Create the getter function(s). We'll start by

# creating functions like _SO_get_columnName,

# then if there's no function named _get_columnName

# we'll alias that to _SO_get_columnName. This

# allows a sort of super call, even though there's

# no superclass that defines the database access.

if sqlmeta.cacheValues:

# We create a method here, which is just a function

# that takes "self" as the first argument.

getter = eval(

'lambda self: self._SO_loadValue(%s)' %

repr(instanceName(name)))

else:

# If we aren't caching values, we just call the

# function _SO_getValue, which fetches from the

# database.

getter = eval('lambda self: self._SO_getValue(%s)' % repr(name))

setattr(soClass, rawGetterName(name), getter)

# Here if the _get_columnName method isn't in the

# definition, we add it with the default

# _SO_get_columnName definition.

if not hasattr(soClass, getterName(name)) or (name == 'childName'):

setattr(soClass, getterName(name), getter)

sqlmeta._plainGetters[name] = 1

#################################################

# Create the setter function(s)

# Much like creating the getters, we will create

# _SO_set_columnName methods, and then alias them

# to _set_columnName if the user hasn't defined

# those methods themself.

# @@: This is lame; immutable right now makes it unsettable,

# making the table read-only

if not column.immutable:

# We start by just using the _SO_setValue method

setter = eval(

'lambda self, val: self._SO_setValue'

'(%s, val, self.%s, self.%s)' % (

repr(name),

'_SO_from_python_%s' % name, '_SO_to_python_%s' % name))

setattr(soClass, '_SO_from_python_%s' % name, column.from_python)

setattr(soClass, '_SO_to_python_%s' % name, column.to_python)

setattr(soClass, rawSetterName(name), setter)

# Then do the aliasing

if not hasattr(soClass, setterName(name)) or (name == 'childName'):

setattr(soClass, setterName(name), setter)

# We keep track of setters that haven't been

# overridden, because we can combine these

# set columns into one SQL UPDATE query.

sqlmeta._plainSetters[name] = 1

##################################################

# Here we check if the column is a foreign key, in

# which case we need to make another method that

# fetches the key and constructs the sister

# SQLObject instance.

if column.foreignKey:

# We go through the standard _SO_get_columnName deal

# we're giving the object, not the ID of the

# object this time:

origName = column.origName

if sqlmeta.cacheValues:

# self._SO_class_className is a reference

# to the class in question.

getter = eval(

'lambda self: self._SO_foreignKey'

'(self._SO_loadValue(%r), self._SO_class_%s, %s)' %

(instanceName(name), column.foreignKey,

column.refColumn and repr(column.refColumn)))

else:

# Same non-caching version as above.

getter = eval(

'lambda self: self._SO_foreignKey'

'(self._SO_getValue(%s), self._SO_class_%s, %s)' %

(repr(name), column.foreignKey,

column.refColumn and repr(column.refColumn)))

setattr(soClass, rawGetterName(origName), getter)

# And we set the _get_columnName version

if not hasattr(soClass, getterName(origName)):

setattr(soClass, getterName(origName), getter)

sqlmeta._plainForeignGetters[origName] = 1

if not column.immutable:

# The setter just gets the ID of the object,

# and then sets the real column.

setter = eval(

'lambda self, val: '

'setattr(self, %s, self._SO_getID(val, %s))' %

(repr(name), column.refColumn and repr(column.refColumn)))

setattr(soClass, rawSetterName(origName), setter)

if not hasattr(soClass, setterName(origName)):

setattr(soClass, setterName(origName), setter)

sqlmeta._plainForeignSetters[origName] = 1

classregistry.registry(sqlmeta.registry).addClassCallback(

column.foreignKey,

lambda foreign, me, attr: setattr(me, attr, foreign),

soClass, '_SO_class_%s' % column.foreignKey)

if column.alternateMethodName:

func = eval(

'lambda cls, val, connection=None: '

'cls._SO_fetchAlternateID(%s, %s, val, connection=connection)'

% (repr(column.name), repr(column.dbName)))

setattr(soClass, column.alternateMethodName, classmethod(func))

if changeSchema:

conn = connection or soClass._connection

conn.addColumn(sqlmeta.table, column)

if soClass._SO_finishedClassCreation:

makeProperties(soClass)

for func in post_funcs:

func(soClass, column)

@classmethod

def addColumnsFromDatabase(sqlmeta, connection=None):

soClass = sqlmeta.soClass

conn = connection or soClass._connection

for columnDef in conn.columnsFromSchema(sqlmeta.table, soClass):

if columnDef.name not in sqlmeta.columnDefinitions:

if isinstance(columnDef.name, unicode_type) and PY2:

columnDef.name = columnDef.name.encode('ascii')

sqlmeta.addColumn(columnDef)

@classmethod

def delColumn(cls, column, changeSchema=False, connection=None):

sqlmeta = cls

soClass = sqlmeta.soClass

if isinstance(column, str):

if column in sqlmeta.columns:

column = sqlmeta.columns[column]

elif column + 'ID' in sqlmeta.columns:

column = sqlmeta.columns[column + 'ID']

else:

raise ValueError('Unknown column ' + column)

if isinstance(column, col.Col):

for c in sqlmeta.columns.values():

if column is c.columnDef:

column = c

break

else:

raise IndexError(

"Column with definition %r not found" % column)

post_funcs = []

cls.send(events.DeleteColumnSignal, cls.soClass, connection,

column.name, column, post_funcs)

name = column.name

del sqlmeta.columns[name]

del sqlmeta.columnDefinitions[name]

sqlmeta.columnList.remove(column)

delattr(soClass, rawGetterName(name))

if name in sqlmeta._plainGetters:

delattr(soClass, getterName(name))

delattr(soClass, rawSetterName(name))

if name in sqlmeta._plainSetters:

delattr(soClass, setterName(name))

if column.foreignKey:

delattr(soClass,

rawGetterName(soClass.sqlmeta.style.

instanceIDAttrToAttr(name)))

if name in sqlmeta._plainForeignGetters:

delattr(soClass, getterName(name))

delattr(soClass,

rawSetterName(soClass.sqlmeta.style.

instanceIDAttrToAttr(name)))

if name in sqlmeta._plainForeignSetters:

delattr(soClass, setterName(name))

if column.alternateMethodName:

delattr(soClass, column.alternateMethodName)

if changeSchema:

conn = connection or soClass._connection

conn.delColumn(sqlmeta, column)

if soClass._SO_finishedClassCreation:

unmakeProperties(soClass)

makeProperties(soClass)

for func in post_funcs:

func(soClass, column)

########################################

# Join handling

########################################

@classmethod

def addJoin(cls, joinDef):

sqlmeta = cls

soClass = cls.soClass

# The name of the method we'll create. If it's

# automatically generated, it's generated by the

# join class.

join = joinDef.withClass(soClass)

meth = join.joinMethodName

sqlmeta.joins.append(join)

index = len(sqlmeta.joins) - 1

if joinDef not in sqlmeta.joinDefinitions:

sqlmeta.joinDefinitions.append(joinDef)

# The function fetches the join by index, and

# then lets the join object do the rest of the

# work:

func = eval(

'lambda self: self.sqlmeta.joins[%i].performJoin(self)' % index)

# And we do the standard _SO_get_... _get_... deal

setattr(soClass, rawGetterName(meth), func)

if not hasattr(soClass, getterName(meth)):

setattr(soClass, getterName(meth), func)

sqlmeta._plainJoinGetters[meth] = 1

# Some joins allow you to remove objects from the

# join.

if hasattr(join, 'remove'):

# Again, we let it do the remove, and we do the

# standard naming trick.

func = eval(

'lambda self, obj: self.sqlmeta.joins[%i].remove(self, obj)' %

index)

setattr(soClass, '_SO_remove' + join.addRemoveName, func)

if not hasattr(soClass, 'remove' + join.addRemoveName):

setattr(soClass, 'remove' + join.addRemoveName, func)

sqlmeta._plainJoinRemovers[meth] = 1

# Some joins allow you to add objects.

if hasattr(join, 'add'):

# And again...

func = eval(

'lambda self, obj: self.sqlmeta.joins[%i].add(self, obj)' %

index)

setattr(soClass, '_SO_add' + join.addRemoveName, func)

if not hasattr(soClass, 'add' + join.addRemoveName):

setattr(soClass, 'add' + join.addRemoveName, func)

sqlmeta._plainJoinAdders[meth] = 1

if soClass._SO_finishedClassCreation:

makeProperties(soClass)

@classmethod

def delJoin(sqlmeta, joinDef):

soClass = sqlmeta.soClass

for join in sqlmeta.joins:

# previously deleted joins will be None, so it must

# be skipped or it'll error out on the next line.

if join is None:

continue

if joinDef is join.joinDef:

break

else:

raise IndexError(

"Join %r not found in class %r (from %r)"

% (joinDef, soClass, sqlmeta.joins))

meth = join.joinMethodName

sqlmeta.joinDefinitions.remove(joinDef)

for i in range(len(sqlmeta.joins)):

if sqlmeta.joins[i] is join:

# Have to leave None, because we refer to joins

# by index.

sqlmeta.joins[i] = None

delattr(soClass, rawGetterName(meth))

if meth in sqlmeta._plainJoinGetters:

delattr(soClass, getterName(meth))

if hasattr(join, 'remove'):

delattr(soClass, '_SO_remove' + join.addRemovePrefix)

if meth in sqlmeta._plainJoinRemovers:

delattr(soClass, 'remove' + join.addRemovePrefix)

if hasattr(join, 'add'):

delattr(soClass, '_SO_add' + join.addRemovePrefix)

if meth in sqlmeta._plainJoinAdders:

delattr(soClass, 'add' + join.addRemovePrefix)

if soClass._SO_finishedClassCreation:

unmakeProperties(soClass)

makeProperties(soClass)

########################################

# Indexes

########################################

@classmethod

def addIndex(cls, indexDef):

cls.indexDefinitions.append(indexDef)

index = indexDef.withClass(cls.soClass)

cls.indexes.append(index)

setattr(cls.soClass, index.name, index)

########################################

# Utility methods

########################################

@classmethod

def getColumns(sqlmeta):

return sqlmeta.columns.copy()

def asDict(self):

"""

Return the object as a dictionary of columns to values.

"""

result = {}

for key in self.getColumns():

result[key] = getattr(self.instance, key)

result['id'] = self.instance.id

return result

@classmethod

def expireAll(sqlmeta, connection=None):

"""

Expire all instances of this class.

"""

soClass = sqlmeta.soClass

connection = connection or soClass._connection

cache_set = connection.cache

cache_set.weakrefAll(soClass)

for item in cache_set.getAll(soClass):

item.expire()

sqlhub = dbconnection.ConnectionHub()

# Turning it on gives earlier warning about things

# that will be deprecated (having this off we won't flood people

# with warnings right away).

warnings_level = 1

exception_level = None

# Current levels:

# 1) Actively deprecated

# 2) Deprecated after 1

# 3) Deprecated after 2

def deprecated(message, level=1, stacklevel=2):

if exception_level is not None and exception_level <= level:

raise NotImplementedError(message)

if warnings_level is not None and warnings_level <= level:

warnings.warn(message, DeprecationWarning, stacklevel=stacklevel)

# if sys.version_info[:2] < (2, 7):

# deprecated("Support for Python 2.6 has been declared obsolete "

# "and will be removed in the next release of SQLObject")

def setDeprecationLevel(warning=1, exception=None):

"""

Set the deprecation level for SQLObject. Low levels are more

actively being deprecated. Any warning at a level at or below

``warning`` will give a warning. Any warning at a level at or

below ``exception`` will give an exception. You can use a higher

``exception`` level for tests to help upgrade your code. ``None``

for either value means never warn or raise exceptions.

The levels currently mean:

1) Deprecated in current version. Will be removed in next version.

2) Planned to deprecate in next version, remove later.

3) Planned to deprecate sometime, remove sometime much later.

As the SQLObject versions progress, the deprecation level of

specific features will go down, indicating the advancing nature of

the feature's doom. We'll try to keep features at 1 for a major

revision.

As time continues there may be a level 0, which will give a useful

error message (better than ``AttributeError``) but where the

feature has been fully removed.

"""

global warnings_level, exception_level

warnings_level = warning

exception_level = exception

class _sqlmeta_attr(object):

def __init__(self, name, deprecation_level):

self.name = name

self.deprecation_level = deprecation_level

def __get__(self, obj, type=None):

if self.deprecation_level is not None:

deprecated(

'Use of this attribute should be replaced with '

'.sqlmeta.%s' % self.name, level=self.deprecation_level)

return getattr((type or obj).sqlmeta, self.name)

_postponed_local = local()

# SQLObject is the superclass for all SQLObject classes, of

# course. All the deeper magic is done in MetaSQLObject, and

# only lesser magic is done here. All the actual work is done

# here, though -- just automatic method generation (like

# methods and properties for each column) is done in

# MetaSQLObject.

class SQLObject(with_metaclass(declarative.DeclarativeMeta, object)):

_connection = sqlhub

sqlmeta = sqlmeta

# DSM: The _inheritable attribute controls wheter the class can by

# DSM: inherited 'logically' with a foreignKey and a back reference.

_inheritable = False # Is this class inheritable?

_parent = None # A reference to the parent instance

childName = None # Children name (to be able to get a subclass)

# The law of Demeter: the class should not call another classes by name

SelectResultsClass = SelectResults

def __classinit__(cls, new_attrs):

# This is true if we're initializing the SQLObject class,

# instead of a subclass:

is_base = cls.__bases__ == (object,)

cls._SO_setupSqlmeta(new_attrs, is_base)

implicitColumns = _collectAttributes(cls, new_attrs, col.Col)

implicitJoins = _collectAttributes(cls, new_attrs, joins.Join)

implicitIndexes = _collectAttributes(cls, new_attrs,

index.DatabaseIndex)

if not is_base:

cls._SO_cleanDeprecatedAttrs(new_attrs)

if '_connection' in new_attrs:

connection = new_attrs['_connection']

del cls._connection

assert 'connection' not in new_attrs

elif 'connection' in new_attrs:

connection = new_attrs['connection']

del cls.connection

else:

connection = None

cls._SO_finishedClassCreation = False

######################################################

# Set some attributes to their defaults, if necessary.

# First we get the connection:

if not connection and not getattr(cls, '_connection', None):

mod = sys.modules[cls.__module__]

# See if there's a __connection__ global in

# the module, use it if there is.

if hasattr(mod, '__connection__'):

connection = mod.__connection__

# Do not check hasattr(cls, '_connection') here - it is possible

# SQLObject parent class has a connection attribute that came

# from sqlhub, e.g.; check __dict__ only.

if connection and ('_connection' not in cls.__dict__):

cls.setConnection(connection)

sqlmeta = cls.sqlmeta

# We have to check if there are columns in the inherited

# _columns where the attribute has been set to None in this

# class. If so, then we need to remove that column from

# _columns.

for key in sqlmeta.columnDefinitions.keys():

if (key in new_attrs and new_attrs[key] is None):

del sqlmeta.columnDefinitions[key]

for column in sqlmeta.columnDefinitions.values():

sqlmeta.addColumn(column)

for column in implicitColumns:

sqlmeta.addColumn(column)

# Now the class is in an essentially OK-state, so we can

# set up any magic attributes:

declarative.setup_attributes(cls, new_attrs)

if sqlmeta.fromDatabase:

sqlmeta.addColumnsFromDatabase()

for j in implicitJoins:

sqlmeta.addJoin(j)

for i in implicitIndexes:

sqlmeta.addIndex(i)

def order_getter(o):

return o.creationOrder

sqlmeta.columnList.sort(key=order_getter)

sqlmeta.indexes.sort(key=order_getter)

sqlmeta.indexDefinitions.sort(key=order_getter)

# Joins cannot be sorted because addJoin created accessors

# that remember indexes.

# sqlmeta.joins.sort(key=order_getter)

sqlmeta.joinDefinitions.sort(key=order_getter)

# We don't setup the properties until we're finished with the

# batch adding of all the columns...

cls._notifyFinishClassCreation()

cls._SO_finishedClassCreation = True

makeProperties(cls)

# We use the magic "q" attribute for accessing lazy

# SQL where-clause generation. See the sql module for

# more.

if not is_base:

cls.q = sqlbuilder.SQLObjectTable(cls)

cls.j = sqlbuilder.SQLObjectTableWithJoins(cls)

classregistry.registry(sqlmeta.registry).addClass(cls)

@classmethod

def _SO_setupSqlmeta(cls, new_attrs, is_base):

"""

This fixes up the sqlmeta attribute. It handles both the case

where no sqlmeta was given (in which we need to create another

subclass), or the sqlmeta given doesn't have the proper

inheritance. Lastly it calls sqlmeta.setClass, which handles

much of the setup.

"""

if ('sqlmeta' not in new_attrs and not is_base):

# We have to create our own subclass, usually.

# type(className, bases_tuple, attr_dict) creates a new subclass.

cls.sqlmeta = type('sqlmeta', (cls.sqlmeta,), {})

if not issubclass(cls.sqlmeta, sqlmeta):

# We allow no superclass and an object superclass, instead

# of inheriting from sqlmeta; but in that case we replace

# the class and just move over its attributes:

assert cls.sqlmeta.__bases__ in ((), (object,)), (

"If you do not inherit your sqlmeta class from "

"sqlobject.sqlmeta, it must not inherit from any other "

"class (your sqlmeta inherits from: %s)"

% cls.sqlmeta.__bases__)

for base in cls.__bases__:

superclass = getattr(base, 'sqlmeta', None)

if superclass:

break

else:

assert 0, (

"No sqlmeta class could be found in any superclass "

"(while fixing up sqlmeta %r inheritance)"

% cls.sqlmeta)

values = dict(cls.sqlmeta.__dict__)

for key in list(values.keys()):

if key.startswith('__') and key.endswith('__'):

# Magic values shouldn't be passed through:

del values[key]

cls.sqlmeta = type('sqlmeta', (superclass,), values)

if not is_base: # Do not pollute the base sqlmeta class

cls.sqlmeta.setClass(cls)

@classmethod

def _SO_cleanDeprecatedAttrs(cls, new_attrs):

"""

This removes attributes on SQLObject subclasses that have

been deprecated; they are moved to the sqlmeta class, and

a deprecation warning is given.

"""

for attr in ():

if attr in new_attrs:

deprecated("%r is deprecated and read-only; please do "

"not use it in your classes until it is fully "

"deprecated" % attr, level=1, stacklevel=5)

@classmethod

def get(cls, id, connection=None, selectResults=None):

assert id is not None, \

'None is not a possible id for %s' % cls.__name__

id = cls.sqlmeta.idType(id)

if connection is None:

cache = cls._connection.cache

else:

cache = connection.cache

# This whole sequence comes from Cache.CacheFactory's

# behavior, where a None returned means a cache miss.

val = cache.get(id, cls)

if val is None:

try:

val = cls(_SO_fetch_no_create=1)

val._SO_validatorState = sqlbuilder.SQLObjectState(val)

val._init(id, connection, selectResults)

cache.put(id, cls, val)

finally:

cache.finishPut(cls)

elif selectResults and not val.sqlmeta.dirty:

val._SO_writeLock.acquire()

try:

val._SO_selectInit(selectResults)

val.sqlmeta.expired = False

finally:

val._SO_writeLock.release()

return val

@classmethod

def _notifyFinishClassCreation(cls):

pass

def _init(self, id, connection=None, selectResults=None):

assert id is not None

# This function gets called only when the object is

# created, unlike __init__ which would be called

# anytime the object was returned from cache.

self.id = id

self._SO_writeLock = threading.Lock()

# If no connection was given, we'll inherit the class

# instance variable which should have a _connection

# attribute.

if (connection is not None) and \

(getattr(self, '_connection', None) is not connection):

self._connection = connection

# Sometimes we need to know if this instance is

# global or tied to a particular connection.

# This flag tells us that:

self.sqlmeta._perConnection = True

if not selectResults:

dbNames = [col.dbName for col in self.sqlmeta.columnList]

selectResults = self._connection._SO_selectOne(self, dbNames)

if not selectResults:

raise SQLObjectNotFound(

"The object %s by the ID %s does not exist" % (

self.__class__.__name__, self.id))

self._SO_selectInit(selectResults)

self._SO_createValues = {}

self.sqlmeta.dirty = False

def _SO_loadValue(self, attrName):

try:

return getattr(self, attrName)

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