Update readthedocs-environment.json file when env vars are added/deleted

readthedocs/doc_builder/python_environments.py

@@ -149,6 +149,7 @@ def is_obsolete(self):
         * the Python version (e.g. 2.7, 3, 3.6, etc)
         * the Docker image name
         * the Docker image hash
+        * the environment variables hash
 
         :returns: ``True`` when it's obsolete and ``False`` otherwise
 
@@ -174,6 +175,7 @@ def is_obsolete(self):
 
         env_python = environment_conf.get('python', {})
         env_build = environment_conf.get('build', {})
+        envvars_hash = environment_conf.get('envvars_hash', None)
 
         # By defaulting non-existent options to ``None`` we force a wipe since
         # we don't know how the environment was created
@@ -193,12 +195,18 @@ def is_obsolete(self):
         # (e.g. ``2`` or ``3``) we won't know exactly which exact version was
         # used to create the venv but we can still compare it against the new
         # one coming from the project version config.
+        print(envvars_hash, self._get_envvars_hash())
         return any([
             env_python_version != self.config.python_full_version,
             env_build_image != build_image,
             env_build_hash != image_hash,
+            envvars_hash != self._get_envvars_hash(),
         ])
 
+    def _get_envvars_hash(self):
+        env_vars = self.version.project.environmentvariable_set.values_list('name', 'value')
+        return hash(tuple(env_vars))
+
     def save_environment_json(self):
         """
         Save on builders disk data about the environment used to build docs.
@@ -208,6 +216,7 @@ def save_environment_json(self):
         - python.version
         - build.image
         - build.hash
+        - envvars_hash
         """
         data = {
             'python': {
@@ -224,6 +233,10 @@ def save_environment_json(self):
                 },
             })
 
+        data.update({
+            'envvars_hash': self._get_envvars_hash(),
+        })
+
         with open(self.environment_json_path(), 'w') as fpath:
             # Compatibility for Py2 and Py3. ``io.TextIOWrapper`` expects
             # unicode but ``json.dumps`` returns str in Py2.

readthedocs/rtd_tests/tests/test_doc_building.py

@@ -1476,6 +1476,9 @@ def test_save_environment_json(self, load_config):
             python_env.save_environment_json()
             json_data = json.load(open(python_env.environment_json_path()))
 
+        envvars = self.version.project.environmentvariable_set.values_list('name', 'value')
+        envvars_hash = hash(tuple(envvars))
+
         expected_data = {
             'build': {
                 'image': 'readthedocs/build:2.0',
@@ -1484,6 +1487,7 @@ def test_save_environment_json(self, load_config):
             'python': {
                 'version': 2.7,
             },
+            'envvars_hash': envvars_hash
         }
         self.assertDictEqual(json_data, expected_data)
 
@@ -1610,9 +1614,10 @@ def test_is_obsolete_with_json_same_data_as_version(self, load_config):
             build_env=self.build_env,
             config=config,
         )
-        env_json_data = '{"build": {"image": "readthedocs/build:2.0", "hash": "a1b2c3"}, "python": {"version": 3.5}}'  # noqa
-        with patch('os.path.exists') as exists, patch('readthedocs.doc_builder.python_environments.open', mock_open(read_data=env_json_data)) as _open:  # noqa
+        env_json_data = '{"build": {"image": "readthedocs/build:2.0", "hash": "a1b2c3"}, "python": {"version": 3.5}, "envvars_hash": 1234}'  # noqa
+        with patch('os.path.exists') as exists, patch('readthedocs.doc_builder.python_environments.PythonEnvironment._get_envvars_hash') as get_hash, patch('readthedocs.doc_builder.python_environments.open', mock_open(read_data=env_json_data)) as _open:  # noqa
             exists.return_value = True
+            get_hash.return_value = 1234
             self.assertFalse(python_env.is_obsolete)
 
     @mock.patch('readthedocs.doc_builder.config.load_config')