From: W. Trevor King <wking@drexel.edu>
Date: Thu, 12 Aug 2010 17:59:26 +0000 (-0400)
Subject: Add hooke.compat.forking to fix Python's ImportError issue8534.
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=9ec54544d983489183076006c08124dc6ea3d8b5;p=hooke.git

Add hooke.compat.forking to fix Python's ImportError issue8534.

multiprocessing can have problems importing modules from child processes.  See
  http://bugs.python.org/issue8534
  http://code.google.com/p/hooke/issues/detail?id=40#c17
Importing hooke.compat.forking fixes this bug dynamically.
---

diff --git a/hooke/compat/forking.py b/hooke/compat/forking.py
new file mode 100644
index 0000000..9acf816
--- /dev/null
+++ b/hooke/compat/forking.py
@@ -0,0 +1,109 @@
+# Copyright (C) 2010 W. Trevor King <wking@drexel.edu>
+#
+# This file is part of Hooke.
+#
+# Hooke is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# Hooke is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
+# Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with Hooke.  If not, see
+# <http://www.gnu.org/licenses/>.
+
+"""Dynamically patch :func:`multiprocessing.forking.prepare`.
+
+`prepare` can have trouble `loading modules from .eggs`_ or
+`finding hooke on Windows`_.  Importing this module applies the
+suggested patch dynamically.
+
+.. _loading modules from .eggs: http://bugs.python.org/issue8534
+.. _finding hooke on Windows:
+  http://code.google.com/p/hooke/issues/detail?id=40#c17
+"""
+
+import multiprocessing.forking
+
+
+def prepare(data):
+    '''
+    Try to get current process ready to unpickle process object
+    '''
+    old_main_modules.append(sys.modules['__main__'])
+
+    if 'name' in data:
+        process.current_process().name = data['name']
+
+    if 'authkey' in data:
+        process.current_process()._authkey = data['authkey']
+
+    if 'log_to_stderr' in data and data['log_to_stderr']:
+        util.log_to_stderr()
+
+    if 'log_level' in data:
+        util.get_logger().setLevel(data['log_level'])
+
+    if 'sys_path' in data:
+        sys.path = data['sys_path']
+
+    if 'sys_argv' in data:
+        sys.argv = data['sys_argv']
+
+    if 'dir' in data:
+        os.chdir(data['dir'])
+
+    if 'orig_dir' in data:
+        process.ORIGINAL_DIR = data['orig_dir']
+
+    if 'main_path' in data:
+        main_path = data['main_path']
+        main_name = os.path.splitext(os.path.basename(main_path))[0]
+        if main_name == '__init__':
+            main_name = os.path.basename(os.path.dirname(main_path))
+
+        if main_name != 'ipython':
+            import imp
+
+            if main_path is None:
+                dirs = None
+            elif os.path.basename(main_path).startswith('__init__.py'):
+                dirs = [os.path.dirname(os.path.dirname(main_path))]
+            else:
+                dirs = [os.path.dirname(main_path)]
+
+            assert main_name not in sys.modules, main_name
+            
+            try:
+                main_module = __import__(main_name)
+            except ImportError:
+                file, path_name, etc = imp.find_module(main_name, dirs)
+                
+                try:
+                    # We would like to do "imp.load_module('__main__', ...)"
+                    # here.  However, that would cause 'if __name__ ==
+                    # "__main__"' clauses to be executed.
+                    main_module = imp.load_module(
+                        '__parents_main__', file, path_name, etc
+                        )
+                finally:
+                    if file:
+                        file.close()
+
+            sys.modules['__main__'] = main_module
+            main_module.__name__ = '__main__'
+
+            # Try to make the potentially picklable objects in
+            # sys.modules['__main__'] realize they are in the main
+            # module -- somewhat ugly.
+            for obj in main_module.__dict__.values():
+                try:
+                    if obj.__module__ == '__parents_main__':
+                        obj.__module__ = '__main__'
+                except Exception:
+                    pass
+multiprocessing.forking.prepare = prepare
diff --git a/hooke/hooke.py b/hooke/hooke.py
index d9def05..c4b2200 100644
--- a/hooke/hooke.py
+++ b/hooke/hooke.py
@@ -71,6 +71,7 @@ from . import playlist
 from . import plugin as plugin_mod
 from . import driver as driver_mod
 from . import ui
+from .compat import forking as forking  # dynamically patch multiprocessing.forking
 
 
 class Hooke (object):