Actions: use local plinth in development mode

Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

actions/test_path

@@ -0,0 +1,24 @@
+#!/usr/bin/python3
+# -*- mode: python -*-
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+"""
+Helper to test whether action scripts use the correct PYTHONPATH.
+"""
+
+import plinth
+print(plinth.__file__)

plinth/actions.py

@@ -168,17 +168,33 @@ def _run(action, options=None, input=None, run_in_background=False,
         cmd += list(options)  # No escaping necessary
 
     # Contract 1: commands can run via sudo.
+    sudo_call = []
     if run_as_root:
-        cmd = ['sudo', '-n'] + cmd
+        sudo_call = ['sudo', '-n']
     elif become_user:
-        cmd = ['sudo', '-n', '-u', become_user] + cmd
+        sudo_call = ['sudo', '-n', '-u', become_user]
+    if cfg.develop and sudo_call:
+        # Passing 'env' does not work with sudo, so append the PYTHONPATH
+        # as part of the command
+        pythonpath = _get_local_pythonpath()
+        sudo_call += ["PYTHONPATH=%s" % pythonpath]
+    if sudo_call:
+        cmd = sudo_call + cmd
 
     LOGGER.info('Executing command - %s', cmd)
 
     # Contract 3C: don't interpret shell escape sequences.
     # Contract 5 (and 6-ish).
-    proc = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE,
-                            stderr=subprocess.PIPE, shell=False)
+    kwargs = {
+        "stdin": subprocess.PIPE,
+        "stdout": subprocess.PIPE,
+        "stderr": subprocess.PIPE,
+        "shell": False,
+    }
+    if cfg.develop:
+        # In development mode pass on local pythonpath to access Plinth
+        kwargs['env'] = {'PYTHONPATH': _get_local_pythonpath()}
+    proc = subprocess.Popen(cmd, **kwargs)
 
     if not run_in_background:
         output, error = proc.communicate(input=input)
@@ -192,3 +208,17 @@ def _run(action, options=None, input=None, run_in_background=False,
         return output
     else:
         return proc
+
+def _get_local_pythonpath():
+    """Use local plinth folder in pythonpath instead of system plinth"""
+    pythonpath = cfg.root
+    try:
+        current_pythonpath = os.environ['PYTHONPATH']
+    except KeyError:
+        pass
+    else:
+        current_pythonpath = current_pythonpath.strip(os.path.pathsep)
+        if current_pythonpath:
+            pythonpath += os.path.pathsep.join([pythonpath,
+                                               current_pythonpath])
+    return pythonpath

plinth/tests/test_actions.py

@@ -44,11 +44,11 @@ class TestActions(unittest.TestCase):
         """Initial setup for all the classes."""
         cls.action_directory = tempfile.TemporaryDirectory()
         cfg.actions_dir = cls.action_directory.name
+        actions_dir = os.path.join(os.path.dirname(__file__), '..', '..',
+            'actions')
 
-        shutil.copy(
-            os.path.join(
-                os.path.dirname(__file__), '..', '..', 'actions', 'packages'),
-            cfg.actions_dir)
+        shutil.copy(os.path.join(actions_dir, 'packages'), cfg.actions_dir)
+        shutil.copy(os.path.join(actions_dir, 'test_path'), cfg.actions_dir)
         shutil.copy('/bin/echo', cfg.actions_dir)
         shutil.copy('/usr/bin/id', cfg.actions_dir)
 
@@ -166,3 +166,23 @@ class TestActions(unittest.TestCase):
         # An ActionError is raised in this case.
         with self.assertRaises(ActionError):
             superuser_run('packages', ['is-package-manager-busy'])
+
+    @unittest.skipUnless(euid == 0, 'Needs to be root')
+    def test_action_path(self):
+        """Test that in development mode, python action scripts get the
+        correct PYTHONPATH"""
+        try:
+            cfg.develop = True
+            self._clear_env()
+            plinth_path = run('test_path').strip()
+            su_plinth_path = superuser_run('test_path').strip()
+            self.assertTrue(plinth_path.startswith(cfg.root))
+            self.assertEquals(plinth_path, su_plinth_path)
+        finally:
+            cfg.develop = False
+
+    def _clear_env(self):
+        try:
+            del os.environ['PYTHONPATH']
+        except KeyError:
+            pass