Initial Fork from https://bitbucket.org/raphaelmutschler/calibreserver/

lib/sqlalchemy/orm/sync.py

@@ -0,0 +1,118 @@
+# orm/sync.py
+# Copyright (C) 2005-2013 the SQLAlchemy authors and contributors <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""private module containing functions used for copying data
+between instances based on join conditions.
+
+"""
+
+from . import exc, util as orm_util, attributes
+
+
+def populate(source, source_mapper, dest, dest_mapper,
+                        synchronize_pairs, uowcommit, flag_cascaded_pks):
+    source_dict = source.dict
+    dest_dict = dest.dict
+
+    for l, r in synchronize_pairs:
+        try:
+            # inline of source_mapper._get_state_attr_by_column
+            prop = source_mapper._columntoproperty[l]
+            value = source.manager[prop.key].impl.get(source, source_dict,
+                                                    attributes.PASSIVE_OFF)
+        except exc.UnmappedColumnError:
+            _raise_col_to_prop(False, source_mapper, l, dest_mapper, r)
+
+        try:
+            # inline of dest_mapper._set_state_attr_by_column
+            prop = dest_mapper._columntoproperty[r]
+            dest.manager[prop.key].impl.set(dest, dest_dict, value, None)
+        except exc.UnmappedColumnError:
+            _raise_col_to_prop(True, source_mapper, l, dest_mapper, r)
+
+        # technically the "r.primary_key" check isn't
+        # needed here, but we check for this condition to limit
+        # how often this logic is invoked for memory/performance
+        # reasons, since we only need this info for a primary key
+        # destination.
+        if flag_cascaded_pks and l.primary_key and \
+                    r.primary_key and \
+                    r.references(l):
+            uowcommit.attributes[("pk_cascaded", dest, r)] = True
+
+
+def clear(dest, dest_mapper, synchronize_pairs):
+    for l, r in synchronize_pairs:
+        if r.primary_key:
+            raise AssertionError(
+                "Dependency rule tried to blank-out primary key "
+                "column '%s' on instance '%s'" %
+                (r, orm_util.state_str(dest))
+            )
+        try:
+            dest_mapper._set_state_attr_by_column(dest, dest.dict, r, None)
+        except exc.UnmappedColumnError:
+            _raise_col_to_prop(True, None, l, dest_mapper, r)
+
+
+def update(source, source_mapper, dest, old_prefix, synchronize_pairs):
+    for l, r in synchronize_pairs:
+        try:
+            oldvalue = source_mapper._get_committed_attr_by_column(
+                source.obj(), l)
+            value = source_mapper._get_state_attr_by_column(
+                source, source.dict, l)
+        except exc.UnmappedColumnError:
+            _raise_col_to_prop(False, source_mapper, l, None, r)
+        dest[r.key] = value
+        dest[old_prefix + r.key] = oldvalue
+
+
+def populate_dict(source, source_mapper, dict_, synchronize_pairs):
+    for l, r in synchronize_pairs:
+        try:
+            value = source_mapper._get_state_attr_by_column(
+                source, source.dict, l)
+        except exc.UnmappedColumnError:
+            _raise_col_to_prop(False, source_mapper, l, None, r)
+
+        dict_[r.key] = value
+
+
+def source_modified(uowcommit, source, source_mapper, synchronize_pairs):
+    """return true if the source object has changes from an old to a
+    new value on the given synchronize pairs
+
+    """
+    for l, r in synchronize_pairs:
+        try:
+            prop = source_mapper._columntoproperty[l]
+        except exc.UnmappedColumnError:
+            _raise_col_to_prop(False, source_mapper, l, None, r)
+        history = uowcommit.get_attribute_history(source, prop.key,
+                                        attributes.PASSIVE_NO_INITIALIZE)
+        if bool(history.deleted):
+            return True
+    else:
+        return False
+
+
+def _raise_col_to_prop(isdest, source_mapper, source_column,
+                       dest_mapper, dest_column):
+    if isdest:
+        raise exc.UnmappedColumnError("Can't execute sync rule for "
+                "destination column '%s'; mapper '%s' does not map "
+                "this column.  Try using an explicit `foreign_keys` "
+                "collection which does not include this column (or use "
+                "a viewonly=True relation)." % (dest_column,
+                dest_mapper))
+    else:
+        raise exc.UnmappedColumnError("Can't execute sync rule for "
+                "source column '%s'; mapper '%s' does not map this "
+                "column.  Try using an explicit `foreign_keys` "
+                "collection which does not include destination column "
+                "'%s' (or use a viewonly=True relation)."
+                % (source_column, source_mapper, dest_column))