- [feature] Added include_symbol option to

  EnvironmentContext.configure(),
  specifies a callable which will include/exclude tables
  in their entirety from the autogeneration process
  based on name.  #27

Author: zzzeek

CHANGES

@@ -1,5 +1,11 @@
 0.3.6
 =====
+- [feature] Added include_symbol option to
+  EnvironmentContext.configure(),
+  specifies a callable which will include/exclude tables
+  in their entirety from the autogeneration process
+  based on name.  #27
+
 - [feature] Added year, month, day, hour, minute, second
   variables to file_template.  #59
 

alembic/autogenerate.py

@@ -102,9 +102,11 @@ def compare_metadata(context, metadata):
 # top level
 
 def _produce_migration_diffs(context, template_args,
-                                imports, _include_only=()):
+                                imports, include_symbol=None):
     opts = context.opts
     metadata = opts['target_metadata']
+    include_symbol = opts.get('include_symbol', include_symbol)
+
     if metadata is None:
         raise util.CommandError(
                 "Can't proceed with --autogenerate option; environment "
@@ -116,7 +118,7 @@ def _produce_migration_diffs(context, template_args,
 
     diffs = []
     _produce_net_changes(connection, metadata, diffs,
-                                autogen_context, _include_only)
+                                autogen_context, include_symbol)
     template_args[opts['upgrade_token']] = \
             _indent(_produce_upgrade_commands(diffs, autogen_context))
     template_args[opts['downgrade_token']] = \
@@ -145,17 +147,22 @@ def _indent(text):
 # walk structures
 
 def _produce_net_changes(connection, metadata, diffs, autogen_context,
-                            include_only=None):
+                            include_symbol=None):
     inspector = Inspector.from_engine(connection)
     # TODO: not hardcode alembic_version here ?
     conn_table_names = set(inspector.get_table_names()).\
                             difference(['alembic_version'])
-    if include_only:
-        conn_table_names = conn_table_names.intersection(include_only)
+
 
     metadata_table_names = OrderedSet([table.name
                                 for table in metadata.sorted_tables])
 
+    if include_symbol:
+        conn_table_names = set(name for name in conn_table_names
+                            if include_symbol(name))
+        metadata_table_names = OrderedSet(name for name in metadata_table_names
+                                if include_symbol(name))
+
     _compare_tables(conn_table_names, metadata_table_names,
                     inspector, metadata, diffs, autogen_context)
 

alembic/environment.py

@@ -208,6 +208,7 @@ def configure(self,
             tag=None,
             template_args=None,
             target_metadata=None,
+            include_symbol=None,
             compare_type=False,
             compare_server_default=False,
             upgrade_token="upgrades",
@@ -355,6 +356,21 @@ def my_compare_server_default(context, inspected_column,
          execute
          the two defaults on the database side to compare for equivalence.
 
+        :param include_symbol: A callable function which, given a table name
+         and optional schema name, returns ``True`` or ``False``, indicating
+         if the given table should be considered in the autogenerate sweep.
+         E.g.::
+
+            def include_symbol(tablename, schema=None):
+                return tablename not in ("skip_table_one", "skip_table_two")
+
+            context.configure(
+                # ...
+                include_symbol = include_symbol
+            )
+
+         .. versionadded:: 0.3.6
+
         :param upgrade_token: When autogenerate completes, the text of the
          candidate upgrade operations will be present in this template
          variable when ``script.py.mako`` is rendered.  Defaults to
@@ -408,6 +424,7 @@ def my_compare_server_default(context, inspected_column,
         if template_args and 'template_args' in opts:
             opts['template_args'].update(template_args)
         opts['target_metadata'] = target_metadata
+        opts['include_symbol'] = include_symbol
         opts['upgrade_token'] = upgrade_token
         opts['downgrade_token'] = downgrade_token
         opts['sqlalchemy_module_prefix'] = sqlalchemy_module_prefix

tests/test_autogenerate.py

@@ -164,9 +164,10 @@ def _get_model_schema(cls):
     def test_boolean_gen_upgrade(self):
         template_args = {}
         autogenerate._produce_migration_diffs(self.context,
-            template_args, set(), _include_only=['sometable'])
+            template_args, set(),
+            include_symbol=lambda name: name == 'sometable')
         eq_(
-            template_args['upgrades'],
+            re.sub(r"u'", "'", template_args['upgrades']),
             "### commands auto generated by Alembic - please adjust! ###\n"
             "    op.create_table('sometable',\n"
             "    sa.Column('id', sa.Integer(), nullable=False),\n"
@@ -181,16 +182,17 @@ def test_boolean_gen_downgrade(self):
 
         template_args = {}
         autogenerate._produce_migration_diffs(self.context,
-            template_args, set(), _include_only=['someothertable'])
+            template_args, set(),
+            )
         eq_(
-            template_args['downgrades'],
+            re.sub(r"u'", "'", template_args['downgrades']),
             "### commands auto generated by Alembic - please adjust! ###\n"
             "    op.create_table('someothertable',\n"
-            "    sa.Column(u'id', mysql.INTEGER(display_width=11), "
+            "    sa.Column('id', mysql.INTEGER(display_width=11), "
                 "nullable=False),\n"
-            "    sa.Column(u'value', mysql.TINYINT(display_width=1), "
+            "    sa.Column('value', mysql.TINYINT(display_width=1), "
             "nullable=True),\n"
-            "    sa.PrimaryKeyConstraint(u'id')\n    )\n"
+            "    sa.PrimaryKeyConstraint('id')\n    )\n"
             "    op.drop_table('sometable')\n"
             "    ### end Alembic commands ###"
         )
@@ -331,6 +333,28 @@ def test_render_diffs(self):
     op.drop_table('item')
     ### end Alembic commands ###""")
 
+    def test_include_symbol(self):
+        context = MigrationContext.configure(
+            connection=self.bind.connect(),
+            opts={
+                'compare_type': True,
+                'compare_server_default': True,
+                'target_metadata': self.m2,
+                'include_symbol': lambda name, schema=None:
+                                    name in ('address', 'order'),
+                'upgrade_token': "upgrades",
+                'downgrade_token': "downgrades",
+                'alembic_module_prefix': 'op.',
+                'sqlalchemy_module_prefix': 'sa.',
+            }
+        )
+        template_args = {}
+        autogenerate._produce_migration_diffs(context, template_args, set())
+        assert "alter_column('user'" not in template_args['upgrades']
+        assert "alter_column('user'" not in template_args['downgrades']
+        assert "alter_column('order'" in template_args['upgrades']
+        assert "alter_column('order'" in template_args['downgrades']
+
     def test_skip_null_type_comparison_reflected(self):
         diff = []
         autogenerate._compare_type("sometable", "somecol",