From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Sun, 1 Jul 2007 21:54:10 +0000 (+0000)
Subject: removed ancient "backref" example, updated byroot_tree to not suck so much
X-Git-Tag: rel_0_4_6~139
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=82e1e98683cfefc09a17cff5454f2443800f715f;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

removed ancient "backref" example, updated byroot_tree to not suck so much
---

diff --git a/examples/adjacencytree/byroot_tree.py b/examples/adjacencytree/byroot_tree.py
index bc187ff625..2a869a08fa 100644
--- a/examples/adjacencytree/byroot_tree.py
+++ b/examples/adjacencytree/byroot_tree.py
@@ -4,7 +4,7 @@ advantage of a custom MapperExtension to assemble incoming nodes into their corr
 
 from sqlalchemy import *
 from sqlalchemy.orm import *
-from sqlalchemy.orm.collections import MappedCollection, collection_adapter
+from sqlalchemy.orm.collections import mapped_collection
 from sqlalchemy.util import OrderedDict
 
 engine = create_engine('sqlite:///:memory:', echo=True)
@@ -30,13 +30,6 @@ treedata = Table(
 )
 
 
-class NodeList(OrderedDict, MappedCollection):
-    """Mix OrderedDict and MappedCollection to create a dict-like collection class that keys off node names."""
-
-    def __init__(self, *args, **kw):
-        MappedCollection.__init__(self, keyfunc=lambda node: node.name)
-        OrderedDict.__init__(self, *args, **kw)
-
 class TreeNode(object):
     """a hierarchical Tree class, which adds the concept of a "root node".  The root is 
     the topmost node in a tree, or in other words a node whose parent ID is NULL.  
@@ -45,13 +38,7 @@ class TreeNode(object):
     
     def __init__(self, name):
         self.name = name
-        self.children = NodeList()
         self.root = self
-        self.parent = None
-        self.id = None
-        self.data =None
-        self.parent_id = None
-        self.root_id=None
 
     def _set_root(self, root):
         self.root = root
@@ -61,7 +48,6 @@ class TreeNode(object):
     def append(self, node):
         if isinstance(node, str):
             node = TreeNode(node)
-        node.parent = self
         node._set_root(self.root)
         self.children.append(node)
 
@@ -106,9 +92,7 @@ class TreeLoader(MapperExtension):
         else:
             if isnew or selectcontext.populate_existing:
                 parentnode = selectcontext.identity_map[mapper.identity_key(instance.parent_id)]
-                collection_adapter(parentnode.children).append_without_event(instance)
-        # fire off lazy loader before the instance is part of the session
-        instance.children
+                parentnode.children.append(instance)
         return False
             
 class TreeData(object):
@@ -132,12 +116,19 @@ mapper(TreeNode, trees, properties=dict(
     name=trees.c.node_name,
     parent_id=trees.c.parent_node_id,
     root_id=trees.c.root_node_id,
-    root=relation(TreeNode, primaryjoin=trees.c.root_node_id==trees.c.node_id, remote_side=trees.c.node_id, lazy=None, uselist=False),
-    children=relation(TreeNode, primaryjoin=trees.c.parent_node_id==trees.c.node_id, lazy=None, uselist=True, cascade="delete,save-update", collection_class=NodeList),
-    data=relation(mapper(TreeData, treedata, properties=dict(id=treedata.c.data_id)), cascade="delete,delete-orphan,save-update", lazy=False)
+    root=relation(TreeNode, primaryjoin=trees.c.root_node_id==trees.c.node_id, remote_side=trees.c.node_id, lazy=None),
+    children=relation(TreeNode, 
+        primaryjoin=trees.c.parent_node_id==trees.c.node_id, 
+        lazy=None, 
+        cascade="all", 
+        collection_class=mapped_collection(lambda n:n.name),
+        backref=backref('parent', primaryjoin=trees.c.parent_node_id==trees.c.node_id, remote_side=trees.c.node_id)
+        ),
+    data=relation(TreeData, cascade="all, delete-orphan", lazy=False)
     
 ), extension = TreeLoader())
 
+mapper(TreeData, treedata, properties={'id':treedata.c.data_id})
 
 session = create_session()
 
@@ -174,6 +165,8 @@ node.append('node4')
 node.children['node4'].append('subnode3')
 node.children['node4'].append('subnode4')
 node.children['node4'].children['subnode3'].append('subsubnode1')
+
+session.delete(node.children['node1'])
 del node.children['node1']
 
 print "\n\n\n----------------------------"
diff --git a/examples/backref/backref_tree.py b/examples/backref/backref_tree.py
deleted file mode 100644
index 5f17396731..0000000000
--- a/examples/backref/backref_tree.py
+++ /dev/null
@@ -1,41 +0,0 @@
-from sqlalchemy import *
-
-metadata = BoundMetaData('sqlite:///', echo=True)
-
-class Tree(object):
-    def __init__(self, name='', father=None):
-        self.name = name
-        self.father = father
-    def __str__(self):
-        return '<TreeNode: %s>' % self.name
-    def __repr__(self):
-        return self.__str__()
-        
-table = Table('tree', metadata,
-              Column('id', Integer, primary_key=True),
-              Column('name', String(64), nullable=False),
-              Column('father_id', Integer, ForeignKey('tree.id'), nullable=True))
-table.create()
-
-mapper(Tree, table,
-              properties={
-                'childs':relation(Tree, remote_side=table.c.father_id, primaryjoin=table.c.father_id==table.c.id,  backref=backref('father', remote_side=table.c.id))},
-            )
-
-root = Tree('root')
-child1 = Tree('child1', root)
-child2 = Tree('child2', root)
-child3 = Tree('child3', child1)
-
-child4 = Tree('child4')
-child1.childs.append(child4)
-
-session = create_session()
-session.save(root)
-session.flush()
-
-print root.childs
-print child1.childs
-print child2.childs
-print child2.father
-print child3.father