2 files changed, 210 insertions, 0 deletions

diff --git a/src/mailman/core/initialize.py b/src/mailman/core/initialize.py
index 5da2209fd..39a6ab078 100644
--- a/src/mailman/core/initialize.py
+++ b/src/mailman/core/initialize.py
@@ -50,6 +50,32 @@ from mailman.utilities.modules import call_name
 
 
 
+def search_for_configuration_file():
+    """Search the file system for a configuration file to use.
+
+    This is only called if the -C command line argument was not given.
+    """
+    config_path = os.getenv('MAILMAN_CONFIG_FILE')
+    # Both None and the empty string are considered "missing".
+    if config_path and os.path.exists(config_path):
+        return config_path
+    # ./mailman.cfg
+    config_path = os.path.abspath('mailman.cfg')
+    if os.path.exists(config_path):
+        return config_path
+    # ~/.mailman.cfg
+    config_path = os.path.join(os.getenv('HOME'), '.mailman.cfg')
+    if os.path.exists(config_path):
+        return config_path
+    # /etc/mailman.cfg
+    config_path = '/etc/mailman.cfg'
+    if os.path.exists(config_path):
+        return config_path
+    # Are there any others we should search by default?
+    return None
+
+
+
 # These initialization calls are separated for the testing framework, which
 # needs to do some internal calculations after config file loading and log
 # initialization, but before database initialization.  Generally all other
@@ -78,6 +104,11 @@ def initialize_1(config_path=None, propagate_logs=None):
     # restrictive permissions in order to handle private archives, but it
     # handles that correctly.
     os.umask(007)
+    # config_path will be set if the command line argument -C is given.  That
+    # case overrides all others.  When not given on the command line, the
+    # configuration file is searched for in the file system.
+    if config_path is None:
+        config_path = search_for_configuration_file()
     mailman.config.config.load(config_path)
     # Create the queue and log directories if they don't already exist.
     mailman.config.config.ensure_directories_exist()
diff --git a/src/mailman/tests/test_configfile.py b/src/mailman/tests/test_configfile.py
new file mode 100644
index 000000000..fa89a1ba8
--- /dev/null
+++ b/src/mailman/tests/test_configfile.py
@@ -0,0 +1,179 @@
+# Copyright (C) 2009 by the Free Software Foundation, Inc.
+#
+# This file is part of GNU Mailman.
+#
+# GNU Mailman is free software: you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option)
+# any later version.
+#
+# GNU Mailman 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 General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Test configuration file searching."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'test_suite',
+    ]
+
+
+import os
+import shutil
+import tempfile
+import unittest
+
+from contextlib import contextmanager
+
+from mailman.core.initialize import search_for_configuration_file
+
+
+
+# Here are a couple of context managers that make our tests easier to read.
+@contextmanager
+def fakedirs(path):
+    """Create and clean up a directory hierarchy."""
+    os.makedirs(path)
+    yield
+    shutil.rmtree(path)
+
+
+@contextmanager
+def hackenv(envar, new_value):
+    """Hack the environment temporarily, then reset it."""
+    old_value = os.getenv(envar)
+    os.environ[envar] = new_value
+    try:
+        yield
+    finally:
+        if old_value is None:
+            del os.environ[envar]
+        else:
+            os.environ[envar] = old_value
+
+
+@contextmanager
+def chdir(new_cwd):
+    """Change to the directory, then back again."""
+    old_cwd = os.getcwd()
+    os.chdir(new_cwd)
+    try:
+        yield
+    finally:
+        os.chdir(old_cwd)
+
+
+
+class TestConfigFileBase(unittest.TestCase):
+    """Common test infrastructure."""
+
+    def setUp(self):
+        self._root = tempfile.mkdtemp()
+
+    def tearDown(self):
+        shutil.rmtree(self._root)
+
+    def _make_fake(self, path):
+        if path.startswith('/'):
+            path = path[1:]
+        return os.path.join(self._root, path)
+
+
+class TestConfigFileSearch(TestConfigFileBase):
+    """Test various aspects of searching for configuration files.
+
+    Note that the command line -C option is not tested here.
+    """
+
+    def test_current_working_directory(self):
+        fake_cwd = '/home/alex/mailman/hacking'
+        fake_testdir = self._make_fake(fake_cwd)
+        config_file = os.path.join(fake_testdir, 'mailman.cfg')
+        with fakedirs(fake_testdir):
+            # Write a mostly empty configuration file.
+            with open(os.path.join(fake_testdir, 'mailman.cfg'), 'w') as fp:
+                print >> fp, '# Fake mailman.cfg file'
+            with chdir(fake_testdir):
+                self.assertEqual(search_for_configuration_file(), config_file)
+
+
+class TestConfigFileSearchWithChroot(TestConfigFileBase):
+    """Like `TestConfigFileSearch` but with a special os.path.exists()."""
+
+    def setUp(self):
+        TestConfigFileBase.setUp(self)
+        # We can't actually call os.chroot() unless we're root.  Neither can
+        # we write to say /etc/mailman.cfg without being root (of course we
+        # wouldn't want to even if we could).  The easiest way to fake a file
+        # system that we can write to and test is to hack os.path.exists() to
+        # prepend a temporary directory onto the path it tests.
+        self._os_path_exists = os.path.exists
+        def exists(path):
+            # Strip off the leading slash, otherwise we'll end up with path.
+            return self._os_path_exists(self._make_fake(path))
+        os.path.exists = exists
+
+    def tearDown(self):
+        os.path.exists = self._os_path_exists
+        TestConfigFileBase.tearDown(self)
+
+    def test_baseline(self):
+        # With nothing set, and no configuration files, just return None.
+        self.assertEqual(search_for_configuration_file(), None)
+
+    def test_environment_variable_to_missing_path(self):
+        # Test that $MAILMAN_CONFIG_FILE pointing to a non-existent path still
+        # returns None.
+        with hackenv('MAILMAN_CONFIG_FILE', '/does/not/exist'):
+            self.assertEqual(search_for_configuration_file(), None)
+
+    def test_environment_variable(self):
+        # Test that $MAILMAN_CONFIG_FILE pointing to an existing path returns
+        # that path.
+        fake_home = '/home/geddy/testing/mailman'
+        fake_testdir = self._make_fake(fake_home)
+        config_file = os.path.join(fake_home, 'mailman.cfg')
+        with fakedirs(fake_testdir):
+            # Write a mostly empty configuration file.
+            with open(os.path.join(fake_testdir, 'mailman.cfg'), 'w') as fp:
+                print >> fp, '# Fake mailman.cfg file'
+            with hackenv('MAILMAN_CONFIG_FILE', config_file):
+                self.assertEqual(search_for_configuration_file(), config_file)
+
+    def test_home_dot_file(self):
+        # Test ~/.mailman.cfg
+        fake_home = '/home/neil'
+        fake_testdir = self._make_fake(fake_home)
+        config_file = os.path.join(fake_home, '.mailman.cfg')
+        with fakedirs(fake_testdir):
+            # Write a mostly empty configuration file.
+            with open(os.path.join(fake_testdir, '.mailman.cfg'), 'w') as fp:
+                print >> fp, '# Fake mailman.cfg file'
+            with hackenv('HOME', '/home/neil'):
+                self.assertEqual(search_for_configuration_file(), config_file)
+
+    def test_etc_file(self):
+        # Test /etc/mailman.cfg
+        fake_etc = '/etc'
+        fake_testdir = self._make_fake(fake_etc)
+        config_file = os.path.join(fake_etc, 'mailman.cfg')
+        with fakedirs(fake_testdir):
+            # Write a mostly empty configuration file.
+            with open(os.path.join(fake_testdir, 'mailman.cfg'), 'w') as fp:
+                print >> fp, '# Fake mailman.cfg file'
+            self.assertEqual(search_for_configuration_file(), config_file)
+
+
+
+def test_suite():
+    suite = unittest.TestSuite()
+    suite.addTest(unittest.makeSuite(TestConfigFileSearch))
+    suite.addTest(unittest.makeSuite(TestConfigFileSearchWithChroot))
+    return suite