Correctly handling multiple calls to parse_config()

To solve this, we maintain the list of DefaultNameFactory used in by trainer_config_helper,
and reset the state at the beginning of each parse_config call.

Change-Id: I13c7574dc8f0b6bc6f6b7c92eb425e2c52c926e8

python/paddle/trainer/config_parser.py

@@ -3364,6 +3364,14 @@ def my_fatal(s):
     logger.critical(s)
     raise Exception()
 
+_parse_config_hooks = set()
+def register_parse_config_hook(f):
+    """
+    Register a hook function for parse_config. parse_config will invoke the hook
+    at the beginning of parse. This make it possible to reset global state for
+    for constructing the model.
+    """
+    _parse_config_hooks.add(f)
 
 def parse_config(config_file, config_arg_str):
     '''
@@ -3371,6 +3379,8 @@ def parse_config(config_file, config_arg_str):
     passed to config script as a dictionary CONFIG_ARGS
     '''
     init_config_environment()
+    for hook in _parse_config_hooks:
+        hook()
 
     config_args = {}
 

python/paddle/trainer_config_helpers/default_decorators.py

@@ -78,6 +78,17 @@ class DefaultNameFactory(object):
         """
         pass
 
+    def reset(self):
+        self.__counter__ = 0
+
+
+_name_factories = []
+
+def reset_hook():
+    for factory in _name_factories:
+        factory.reset()
+
+register_parse_config_hook(reset_hook)
 
 def wrap_name_default(name_prefix=None):
     """
@@ -95,7 +106,9 @@ def wrap_name_default(name_prefix=None):
     :return: a decorator to set default name
     :rtype: callable
     """
-    return wrap_param_default(["name"], DefaultNameFactory(name_prefix))
+    factory = DefaultNameFactory(name_prefix)
+    _name_factories.append(factory)
+    return wrap_param_default(["name"], factory)
 
 
 def wrap_param_attr_default(param_names=None, default_factory=None):

python/paddle/trainer_config_helpers/tests/CMakeLists.txt

@@ -4,6 +4,11 @@ add_test(NAME layers_test
         python ${PROJ_ROOT}/python/paddle/trainer_config_helpers/tests/layers_test.py
     WORKING_DIRECTORY ${PROJ_ROOT}/python/paddle)
 
+add_test(NAME test_reset_hook
+  COMMAND ${PROJ_ROOT}/paddle/.set_python_path.sh -d ${PROJ_ROOT}/python/
+        python ${PROJ_ROOT}/python/paddle/trainer_config_helpers/tests/test_rest_hook.py
+    WORKING_DIRECTORY ${PROJ_ROOT}/python/paddle)
+
 if (PROTOBUF_3)
   add_paddle_exe(protobuf_equal
     ProtobufEqualMain.cpp)

python/paddle/trainer_config_helpers/tests/test_reset_hook.py

+# Copyright PaddlePaddle contributors. All Rights Reserved
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import unittest
+from paddle.trainer.config_parser import parse_config
+
+class TestParse(unittest.TestCase):
+
+    def test_parse(self):
+        a = parse_config(
+            'trainer_config_helpers/tests/layers_test_config.py', '')
+        b = parse_config(
+            'trainer_config_helpers/tests/layers_test_config.py', '')
+        self.assertEqual(a, b)
+
+
+if __name__ == '__main__':
+    unittest.main()