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

readthedocs/doc_builder/python_environments.py

@@ -3,6 +3,7 @@
 """An abstraction over virtualenv and Conda environments."""
 
 import copy
+import hashlib
 import itertools
 import json
 import logging
@@ -149,6 +150,7 @@ 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 +176,7 @@ def is_obsolete(self):
 
         env_python = environment_conf.get('python', {})
         env_build = environment_conf.get('build', {})
+        env_vars_hash = environment_conf.get('env_vars_hash', None)
 
         # By defaulting non-existent options to ``None`` we force a wipe since
         # we don't know how the environment was created
@@ -197,8 +200,39 @@ def is_obsolete(self):
             env_python_version != self.config.python_full_version,
             env_build_image != build_image,
             env_build_hash != image_hash,
+            env_vars_hash != self._get_env_vars_hash(),
         ])
 
+    def _get_env_vars(self):
+        """
+        Returns environment variables with their values of the associated project.
+
+        If there are no environment variables, it returns None.
+        """
+        env_vars = self.version.project.environmentvariable_set.values_list('name', 'value')
+        if env_vars.exists():
+            return tuple(env_vars)
+
+    def _get_env_vars_hash(self):
+        """
+        Returns the sha256 hash of all the environment variables and their values.
+
+        If there are no environment variables, it returns the sha256 hash of 'None'.
+        """
+        env_vars = self._get_env_vars()
+        m = hashlib.sha256()
+        if env_vars:
+            for env_var in env_vars:
+                hash_str = '_{var}_{value}_'.format(
+                    var=env_var[0],
+                    value=env_var[1]
+                )
+                m.update(hash_str.encode('utf-8'))
+        else:
+            m.update('None'.encode('utf-8'))
+
+        return m.hexdigest()
+
     def save_environment_json(self):
         """
         Save on builders disk data about the environment used to build docs.
@@ -208,11 +242,13 @@ def save_environment_json(self):
         - python.version
         - build.image
         - build.hash
+        - env_vars_hash
         """
         data = {
             'python': {
                 'version': self.config.python_full_version,
             },
+            'env_vars_hash': self._get_env_vars_hash(),
         }
 
         if isinstance(self.build_env, DockerBuildEnvironment):

readthedocs/rtd_tests/tests/test_doc_building.py

@@ -5,6 +5,7 @@
 * raw subprocess calls like .communicate expects bytes
 * the Command wrappers encapsulate the bytes and expose unicode
 """
+import hashlib
 import json
 import os
 import re
@@ -30,7 +31,7 @@
 )
 from readthedocs.doc_builder.exceptions import BuildEnvironmentError
 from readthedocs.doc_builder.python_environments import Conda, Virtualenv
-from readthedocs.projects.models import Project
+from readthedocs.projects.models import Project, EnvironmentVariable
 from readthedocs.rtd_tests.mocks.environment import EnvironmentMockGroup
 from readthedocs.rtd_tests.mocks.paths import fake_paths_lookup
 from readthedocs.rtd_tests.tests.test_config_integration import create_load
@@ -1469,13 +1470,21 @@ def test_save_environment_json(self, load_config):
             config=config,
         )
 
+        self.assertFalse(self.pip.environmentvariable_set.all().exists())
+        get(EnvironmentVariable, project=self.pip, name='ABCD', value='1234')
+        env_var_str = '_ABCD_1234_'
+        m = hashlib.sha256()
+        m.update(env_var_str.encode('utf-8'))
+        env_vars_hash = m.hexdigest()
+
         with patch(
                 'readthedocs.doc_builder.python_environments.PythonEnvironment.environment_json_path',
                 return_value=tempfile.mktemp(suffix='envjson'),
         ):
             python_env.save_environment_json()
             json_data = json.load(open(python_env.environment_json_path()))
 
+
         expected_data = {
             'build': {
                 'image': 'readthedocs/build:2.0',
@@ -1484,6 +1493,7 @@ def test_save_environment_json(self, load_config):
             'python': {
                 'version': 2.7,
             },
+            'env_vars_hash': env_vars_hash
         }
         self.assertDictEqual(json_data, expected_data)
 
@@ -1610,7 +1620,15 @@ 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
+
+        self.assertFalse(self.pip.environmentvariable_set.all().exists())
+        get(EnvironmentVariable, project=self.pip, name='HELLO', value='WORLD')
+        env_var_str = '_HELLO_WORLD_'
+        m = hashlib.sha256()
+        m.update(env_var_str.encode('utf-8'))
+        env_vars_hash = m.hexdigest()
+
+        env_json_data = '{{"build": {{"image": "readthedocs/build:2.0", "hash": "a1b2c3"}}, "python": {{"version": 3.5}}, "env_vars_hash": "{}"}}'.format(env_vars_hash)  # 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
             exists.return_value = True
             self.assertFalse(python_env.is_obsolete)