implement describe for projected dependencies

Author: dimitri-yatsenko

datajoint/declare.py

@@ -34,17 +34,13 @@ def build_foreign_key_parser_old():
 
 
 def build_foreign_key_parser():
-    left = pp.Literal('(').suppress()
-    right = pp.Literal(')').suppress()
-    attribute_name = pp.Word(pp.srange('[a-z]'), pp.srange('[a-z0-9_]'))
-    new_attrs = pp.Optional(left + pp.delimitedList(attribute_name) + right).setResultsName('new_attrs')
     arrow = pp.Literal('->').suppress()
     lbracket = pp.Literal('[').suppress()
     rbracket = pp.Literal(']').suppress()
     option = pp.Word(pp.srange('[a-zA-Z]'))
     options = pp.Optional(lbracket + pp.delimitedList(option) + rbracket).setResultsName('options')
     ref_table = pp.restOfLine.setResultsName('ref_table')
-    return new_attrs + arrow + options + ref_table
+    return arrow + options + ref_table
 
 
 def build_attribute_parser():
@@ -96,16 +92,16 @@ def compile_foreign_key(line, context, attributes, primary_key, attr_sql, foreig
     from .table import Table
     from .query import Projection
 
-    new_style = False   # See issue #436.  Old style to be deprecated in a future release
+    new_style = True   # See issue #436.  Old style to be deprecated in a future release
     try:
-        result = foreign_key_parser_old.parseString(line)
-    except pp.ParseException as err:
+        result = foreign_key_parser.parseString(line)
+    except pp.ParseException:
         try:
-            result = foreign_key_parser.parseString(line)
+            result = foreign_key_parser_old.parseString(line)
         except pp.ParseBaseException as err:
-            raise DataJointError('Parsing error in line "%s". %s.' % (line, err))
+            raise DataJointError('Parsing error in line "%s". %s.' % (line, err)) from None
         else:
-            new_style = True
+            new_style = False
     try:
         ref = eval(result.ref_table, context)
     except Exception if new_style else NameError:
@@ -129,7 +125,7 @@ def compile_foreign_key(line, context, attributes, primary_key, attr_sql, foreig
 
     # check that dependency is of supported type
     if (not isinstance(ref, (Table, Projection)) or len(ref.restriction) or
-            (isinstance(ref, Projection) and (not isinstance(ref._arg, Table) or not len(ref._arg.restriction)))):
+            (isinstance(ref, Projection) and (not isinstance(ref._arg, Table) or len(ref._arg.restriction)))):
         raise DataJointError('Dependency "%s" is not supported (yet). Use a base table or its projection.' %
                              result.ref_table)
 

datajoint/table.py

@@ -488,15 +488,14 @@ def describe(self, context=None, printout=True):
                                 props=index_props,
                                 class_name=lookup_class_name(parent_name, context) or parent_name)
                         else:
-                            # expression foreign key
+                            # projected foreign key
                             parent_name = list(self.connection.dependencies.in_edges(parent_name))[0][0]
                             lst = [(attr, ref) for attr, ref in fk_props['attr_map'].items() if ref != attr]
-                            definition += '({attr_list}) ->{props} {class_name}{ref_list}\n'.format(
+                            definition += '->{props} {class_name}.proj({proj_list})\n'.format(
                                 attr_list=', '.join(r[0] for r in lst),
                                 props=index_props,
                                 class_name=lookup_class_name(parent_name, context) or parent_name,
-                                ref_list=('' if len(attributes_thus_far) - len(attributes_declared) == 1
-                                          else '(%s)' % ','.join(r[1] for r in lst)))
+                                proj_list=','.join('{}="{}"'.format(a,b) for a, b in lst))
                             attributes_declared.update(fk_props['attr_map'])
             if do_include:
                 attributes_declared.add(attr.name)

tests/schema.py

@@ -260,7 +260,7 @@ class SigTermTable(dj.Computed):
     -> SimpleSource
     """
 
-    def _make_tuples(self, key):
+    def make(self, key):
         os.kill(os.getpid(), signal.SIGTERM)
 
 
@@ -271,12 +271,13 @@ class DecimalPrimaryKey(dj.Lookup):
     """
     contents = zip((0.1, 0.25, 3.99))
 
+
 @schema
 class IndexRich(dj.Manual):
     definition = """
     -> Experiment
     ---
-    (first) ->[unique, nullable] User
+    -> [unique, nullable] User.proj(first="username")
     first_date : date
     value : int
     index (first_date, value)

tests/schema_advanced.py

@@ -108,8 +108,9 @@ class LocalSynapse(dj.Manual):
 
 @schema
 class GlobalSynapse(dj.Manual):
+    # Mix old-style and new-style projected foreign keys
     definition = """
     # a synapse within the slice
-    (pre_slice, pre_cell) -> Cell(slice, cell)
+    -> Cell.proj(pre_slice="slice", pre_cell="cell")
     (post_slice, post_cell)-> Cell(slice, cell)
     """