neo4j_cypher: introducte Query_Transformation, QT_Node_Filter__Doc_ID_Label

1 files changed, 53 insertions, 0 deletions

diff --git a/src/server/neo4j_cypher.py b/src/server/neo4j_cypher.py
index 6537619f..d8d466ea 100644
--- a/src/server/neo4j_cypher.py
+++ b/src/server/neo4j_cypher.py
@@ -51,27 +51,80 @@ class Query_Struct_Type(Enum):
 
 
 
+class Query_Transformation(object):
+    """
+    A query transformation, which may be applied to either a DB_op or a DB_Query
+    """
 
+    def __call__(self, value):
 
+        q_set = []
 
+        if isinstance(value, DB_Query):
+            q_set.append(value)
+        else:  # assume iterable
+            assert hasattr(value, '__iter__')
 
+            for dbq in value:
+                assert isinstance(dbq, DB_Query)
 
+                q_set.append(dbq)
 
+        for dbq in q_set:
+            log.debug('%r' % (dbq))
+            self.apply_to_single_query(dbq)
+            log.debug('%r' % (dbq))
 
+        return value
 
+    def apply_to_single_query(self, dbq):
+        pass
 
+class QT_Node_Filter__Doc_ID_Label(Query_Transformation):
 
+    def __init__(self, doc_id):
+        self.doc_id = doc_id
 
+    def apply_to_single_query(self, dbq):
 
+        doc_id_label = META_LABEL__RZ_DOC_PREFIX + self.doc_id
+        rgx__doc_label = re.compile(r'%s[\w\d_]+' % (META_LABEL__RZ_DOC_PREFIX))
+        assert None != rgx__doc_label.match(doc_id_label), 'Illegal doc ID label: %s' % (doc_id_label)  # validate doc label
 
+        q_type = dbq.query_struct_type
+        c_set = []  # clause set
 
+        if Query_Struct_Type.w == q_type:
+            c_set += dbq.pt_root.clause_set_by_kw('create')
+        if Query_Struct_Type.r == q_type:
+            c_set += dbq.pt_root.clause_set_by_kw('match')
+        if Query_Struct_Type.rw == q_type:
+            c_set += dbq.pt_root.clause_set_by_kw('create')
+            c_set += dbq.pt_root.clause_set_by_kw('match')
 
+        for c in c_set:
 
+            set_of_lbl_set = c.sub_exp_set_by_type(e_label_set, recurse=True)
 
+            if not set_of_lbl_set:  # no label set
+                p_node_or_path_set = c.sub_exp_set_by_type([p_node], recurse=True)
 
+                def f_visit(n, ctx, depth):
+                    if isinstance(n, e_ident) and n.parent.__class__ in [p_node]:
+                        lbl_set = n.spawn_sibling__adjacent(e_label_set)
+                        lbl = lbl_set.spawn_child(e_value)
+                        lbl.value = doc_id_label
 
+                for p_exp in p_node_or_path_set:
+                    p_exp.tree_walk__pre(f_visit=f_visit)
 
+            else:  # append to existing label set
+                for lbl_set in set_of_lbl_set:
+                    if isinstance(lbl_set.parent, p_node):
+                        lbl = lbl_set.spawn_child(e_value)
+                        lbl.value = doc_id_label
 
+            # log.debug('db_q trans: in clause: %s, out clause: %s' % (cur_clause, new_clause))
 
 
         """