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# -*- test-case-name: axiom.test -*-
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from twisted.python.filepath import FilePath
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from axiom.slotmachine import Attribute as inmemory
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from axiom.extime import Time
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_NEEDS_FETCH = object() # token indicating that a value was not found
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class SQLAttribute(inmemory):
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Abstract superclass of all attributes.
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_Not_ an attribute itself.
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def coercer(self, value):
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must return a value equivalent to the data being passed in for it to be
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considered valid for a value of this attribute. for example, 'int' or
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raise NotImplementedError()
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def __init__(self, doc='', indexed=False):
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inmemory.__init__(self, doc)
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self.indexed = indexed
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def infilter(self, pyval, oself):
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used to convert a Python value to something that lives in the database;
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so called because it is called when objects go in to the database. It
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takes a Python value and returns an SQL value.
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raise NotImplementedError()
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def outfilter(self, dbval, oself):
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used to convert an SQL value to something that lives in memory; so
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called because it is called when objects come out of the database. It
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takes an SQL value and returns a Python value.
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# requiredSlots must be called before it's run
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prefix = "_atop_memory_"
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dbprefix = "_atop_store_"
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def requiredSlots(self, modname, classname, attrname):
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self.modname = modname
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self.classname = classname
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self.attrname = attrname
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self.columnName = attrname
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self.underlying = self.prefix + attrname
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self.dbunderlying = self.dbprefix + attrname
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yield self.dbunderlying
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def fullyQualifiedName(self):
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return '.'.join([self.modname,
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def __get__(self, oself, type=None):
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if type is not None and oself is None:
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return ColumnComparer(self, type)
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pyval = getattr(oself, self.underlying, _NEEDS_FETCH)
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st = getattr(oself, 'store')
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if pyval is _NEEDS_FETCH:
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dbval = getattr(oself, self.dbunderlying, _NEEDS_FETCH)
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if dbval is _NEEDS_FETCH:
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raise AttributeError(self.attrname)
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pyval = self.outfilter(dbval, oself)
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setattr(oself, self.underlying, pyval)
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def loaded(self, oself, dbval):
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setattr(oself, self.dbunderlying, dbval)
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delattr(oself, self.underlying) # member_descriptors don't raise
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# attribute errors; what gives? good
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def __set__(self, oself, pyval):
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# convert to dbval later, I guess?
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dbval = self.infilter(pyval, oself)
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oself.__dirty__[self.attrname] = dbval
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setattr(oself, self.underlying, pyval)
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if st is not None and st.autocommit:
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class ColumnComparer:
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def __init__(self, atr, typ):
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self.compared = False # not yet activated
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self.otherComp = None
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def compare(self, other, sqlop):
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assert not self.compared # activation time
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# interim: maybe we want objects later? right now strings should be fine
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if isinstance(other, ColumnComparer):
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self.otherComp = other
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self.sql = ('(%s.%s %s %s.%s)' % (self.type.getTableName(),
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self.attribute.columnName,
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other.type.getTableName(),
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other.attribute.columnName))
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# convert to constant usable in the database
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self.sql = ('(%s.%s %s ?)' % (self.type.getTableName(),
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self.attribute.columnName,
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self.preArgs = [other]
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def __eq__(self, other):
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return self.compare(other, '=')
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def __ne__(self, other):
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return self.compare(other, '!=')
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def __gt__(self, other):
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return self.compare(other, '>')
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def __lt__(self, other):
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return self.compare(other, '<')
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def __ge__(self, other):
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return self.compare(other, '>=')
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def __le__(self, other):
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return self.compare(other, '<=')
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# XXX TODO: improve error reporting
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def getArgsFor(self, store):
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return [self.attribute.infilter(arg, None) for arg in self.preArgs]
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def getTableNames(self):
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names = [self.type.getTableName()]
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if self.otherComp is not None:
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names.append(self.otherComp.type.getTableName())
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return 'ORDER BY %s.%s ASC' % (self.type.getTableName(),
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self.attribute.columnName)
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return 'ORDER BY %s.%s DESC' % (self.type.getTableName(),
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self.attribute.columnName)
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descending = property(_desc)
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ascending = property(_asc)
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def __init__(self, a, b):
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return ' '.join(['(',
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self.__class__.__name__,
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def getArgsFor(self, store):
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return self.a.getArgsFor(store) + self.b.getArgsFor(store)
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def getTableNames(self):
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return (self.a.getTableNames() + self.b.getTableNames())
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class integer(SQLAttribute):
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def infilter(self, pyval, oself):
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class bytes(SQLAttribute):
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Attribute representing a sequence of bytes; this is represented in memory
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def infilter(self, pyval, oself):
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def outfilter(self, dbval, oself):
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class InvalidPathError(ValueError):
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A path that could not be used with the database was attempted to be used
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class text(SQLAttribute):
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Attribute representing a sequence of characters; this is represented in
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memory as a Python 'unicode'.
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def __init__(self, doc='', indexed=False, caseSensitive=False):
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SQLAttribute.__init__(self, doc, indexed)
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self.sqltype = 'TEXT'
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self.sqltype = 'TEXT COLLATE NOCASE'
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self.caseSensitive = caseSensitive
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def infilter(self, pyval, oself):
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if not isinstance(pyval, unicode) or '\x00' in pyval:
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raise TypeError("text must be (unicode string without NULL bytes); not %r" %
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(type(pyval).__name__,))
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def outfilter(self, dbval, oself):
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def infilter(self, pyval, oself):
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mypath = unicode(pyval.path)
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storepath = oself.store.filesdir
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if not mypath.startswith(storepath):
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raise InvalidPathError('%s not in %s' % (mypath, storepath))
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p = mypath[len(storepath):]
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if p.startswith('/'):
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return super(path, self).infilter(p, oself)
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def outfilter(self, dbval, oself):
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fp = FilePath(os.path.join(oself.store.filesdir, dbval))
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class timestamp(integer):
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def infilter(self, pyval, oself):
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return int(pyval.asPOSIXTimestamp() * MICRO)
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def outfilter(self, dbval, oself):
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return Time.fromPOSIXTimestamp(dbval / MICRO)
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class reference(integer):
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def __init__(self, doc='', indexed=True, reftype=None):
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integer.__init__(self, doc, indexed)
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self.reftype = reftype
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def infilter(self, pyval, oself):
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if oself.store != pyval.store:
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raise AttributeError(
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"You can't establish references to items in other stores.")
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if oself.store is None:
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raise AttributeError(
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"TODO: Setting references on items outside of stores is "
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"currently unsupported. Set .store first.")
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def outfilter(self, dbval, oself):
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return oself.store.getItemByID(dbval, autoUpgrade=not oself.__legacy__)
added
removed
Axiom/axiom/attributes.py
