introducing the Link_Ptr concept - able to fuzzy point at a link by src_id, dst_id or both

3 files changed, 67 insertions, 27 deletions

diff --git a/src-py/db_controller.py b/src-py/db_controller.py
index 7cd1af7b..ceb5267c 100644
--- a/src-py/db_controller.py
+++ b/src-py/db_controller.py
@@ -264,28 +264,38 @@ class DBO_match_node_set_by_id_attribute(DBO_match_node_id_set):
         super(DBO_match_node_set_by_id_attribute, self).__init__(filter_attr_map={'id': id_set})
 
 
-class DBO_match_link_set_by_src_or_dst_id_attributes(DB_op):
-    def __init__(self, src_id=None, dst_id=None):
+class DBO_load_link_set(DB_op):
+    def __init__(self, link_ptr_set):
         """
-        match a set of links by source/target node id attributes
+        match a set of sets of links by source/target node id attributes
         
+        This class should be instantiated through a static factory function
+
+        @link_ptr_set link pointer set
         @return: a set of loaded links
         """
-        assert None != src_id or None != dst_id
+        super(DBO_load_link_set, self).__init__()
+        
+        for l_ptr in link_ptr_set:
+            if not l_ptr.src_id:
+                q = "match ()-[r]->({id: {dst_id}}) return r"
+                q_params = {'dst_id': l_ptr.dst_id}
+            elif not l_ptr.dst_id:
+                q = "match ({id: {src_id}})-[r]->() return r"
+                q_params = {'src_id': l_ptr.src_id}
+            else:
+                q = "match ({id: {src_id}})-[r]->({id: {dst_id}}) return r"
+                q_params = {'src_id': l_ptr.src_id, 'dst_id': l_ptr.dst_id}
 
-        super(DBO_match_link_set_by_src_or_dst_id_attributes, self).__init__()
+            self.add_statement(q, q_params)
 
-        if not src_id:
-            q = "match ()-[r]->({id: {dst_id}}) return r"
-            q_params = {'dst_id': dst_id}
-        elif not dst_id:
-            q = "match ({id: {src_id}})-[r]->() return r"
-            q_params = {'src_id': src_id}
-        else:
-            q = "match ({id: {src_id}})-[r]->({id: {dst_id}}) return r"
-            q_params = {'src_id': src_id, 'dst_id': dst_id}
+    @staticmethod
+    def init_from_link_ptr(l_ptr):
+        return DBO_load_link_set([l_ptr])
 
-        self.add_statement(q, q_params)
+    @staticmethod
+    def init_from_link_ptr_set(l_ptr_set):
+        return DBO_load_link_set(l_ptr_set)
 
 class DBO_match_link_id_set(DB_op):
     def __init__(self, filter_type=None, filter_attr_map={}):
diff --git a/src-py/model/model.py b/src-py/model/model.py
index 9ee61397..701074ab 100644
--- a/src-py/model/model.py
+++ b/src-py/model/model.py
@@ -1,4 +1,4 @@
-class link():
+class Link():
     """
     documentation anchor - this class currently carries no implementation
     and only acts as a documentation anchor
@@ -6,4 +6,25 @@ class link():
     link['__src'] - meta attribute for link source
     link['__dst'] - meta attribute for link destination
     """
-    pass
+    
+    class Link_Ptr(dict):
+        def __init__(self, src_id=None, dst_id=None):
+            assert None != src_id or None != dst_id
+            
+            self['__src'] = src_id
+            self['__dst'] = dst_id
+        
+        @property
+        def src_id(self):
+            return self['__src']
+
+        @property
+        def dst_id(self):
+            return self['__dst']
+
+    @staticmethod
+    def link_ptr(src_id=None, dst_id=None):
+        """
+        init from src_id or dst_id attributes - at least one must be provided
+        """
+        return Link.Link_Ptr(src_id, dst_id)
diff --git a/src-py/test_db_controller.py b/src-py/test_db_controller.py
index 4af4cabc..cdc0c5e9 100644
--- a/src-py/test_db_controller.py
+++ b/src-py/test_db_controller.py
@@ -122,19 +122,28 @@ class TestDBController(unittest.TestCase):
         id_set = self.db_ctl.exec_op(op)
         self.assertEqual(len(id_set), 0)
 
-    def test_match_link_set_by_src_or_dst_id_attributes(self):
-        op = dbc.DBO_match_link_set_by_src_or_dst_id_attributes(src_id='person_00', dst_id='skill_00')
-        n_set = self.db_ctl.exec_op(op)
-        self.assertEqual(len(n_set), 1)
+    def test_load_link_set(self):
+        l_ptr = Link.link_ptr(src_id='person_00', dst_id='skill_00')
+        op = dbc.DBO_load_link_set.init_from_link_ptr(l_ptr)
+        l_set = self.db_ctl.exec_op(op)
+        self.assertEqual(len(l_set), 1)
 
-        op = dbc.DBO_match_link_set_by_src_or_dst_id_attributes(src_id='person_00')
-        n_set = self.db_ctl.exec_op(op)
-        self.assertEqual(len(n_set), 2)
+        l_ptr = Link.link_ptr(src_id='person_00')
+        op = dbc.DBO_load_link_set.init_from_link_ptr(l_ptr)
+        l_set = self.db_ctl.exec_op(op)
+        self.assertEqual(len(l_set), 2)
 
-        op = dbc.DBO_match_link_set_by_src_or_dst_id_attributes(dst_id='skill_00')
-        n_set = self.db_ctl.exec_op(op)
-        self.assertEqual(len(n_set), 1)
+        l_ptr = Link.link_ptr(dst_id='skill_00')
+        op = dbc.DBO_load_link_set.init_from_link_ptr(l_ptr)
+        l_set = self.db_ctl.exec_op(op)
+        self.assertEqual(len(l_set), 1)
 
+        # load sets
+        l_ptr_set = [Link.link_ptr(s,d) for (s,d) in [('person_00', 'skill_00'), ('person_00', 'skill_01')]]
+        op = dbc.DBO_load_link_set.init_from_link_ptr_set(l_ptr_set)
+        l_set = self.db_ctl.exec_op(op)
+        self.assertEqual(len(l_set), 2)
+    
     def test_load_node_set_by_DB_id(self):
         """
         test node DB id life cycle