Address review feedback and remove most of my deleted code :)

docs/yaml-config.rst

@@ -80,19 +80,20 @@ The ``build`` block configures specific aspects of the documentation build.
 build.image
 ```````````
 
-* Default: ``2.0``
+
+* Default: :djangosetting:`DOCKER_IMAGE`
 * Options: ``1.0``, ``2.0``, ``latest``
 
-The docker image to use for specific builds.
-This lets users specify a more experimental builder,
+The build image to use for specific builds.
+This lets users specify a more experimental build image,
 if they want to be on the cutting edge.
 
-Certain Python versions require a certain builder,
+Certain Python versions require a certain build image,
 as defined here::
 
-* '1.0': 2, 2.7, 3, 3.4
-* '2.0': 2, 2.7, 3, 3.5
-* 'latest': 2, 2.7, 3, 3.3, 3.4, 3.5, 3.6
+* `'1.0': 2, 2.7, 3, 3.4`
+* `'2.0': 2, 2.7, 3, 3.5`
+* `'latest': 2, 2.7, 3, 3.3, 3.4, 3.5, 3.6`
 
 .. code-block:: yaml
 

readthedocs/doc_builder/config.py

@@ -8,6 +8,8 @@ from builtins import filter, object
 from readthedocs_build.config import load as load_config
 from readthedocs_build.config import BuildConfig, ConfigError, InvalidConfig
 
+from .constants import DOCKER_BUILD_IMAGES, DOCKER_IMAGE
+
 
 class ConfigWrapper(object):
 
@@ -57,7 +59,7 @@ class ConfigWrapper(object):
                 list(
                     filter(
                         lambda x: x < ver + 1,
-                        self._yaml_config.PYTHON_SUPPORTED_VERSIONS,
+                        self._yaml_config.get_valid_python_versions(),
                     )))
         return 'python{0}'.format(ver)
 
@@ -133,8 +135,22 @@ def load_yaml_config(version):
     parsing consistent between projects.
     """
     checkout_path = version.project.checkout_path(version.slug)
+    env_config = {}
+
+    # Get build image to set up the python version validation. Pass in the
+    # build image python limitations to the loaded config so that the versions
+    # can be rejected at validation
+    build_image = DOCKER_BUILD_IMAGES.get(
+        version.project.container_image,
+        DOCKER_BUILD_IMAGES.get(DOCKER_IMAGE, None),
+    )
+    if build_image:
+        env_config = {
+            'python': build_image['python'],
+        }
+
     try:
-        sphinx_env_config = {}
+        sphinx_env_config = env_config.copy()
         sphinx_env_config.update({
             'output_base': '',
             'type': 'sphinx',
@@ -148,9 +164,8 @@ def load_yaml_config(version):
         # This is a subclass of ConfigError, so has to come first
         raise
     except ConfigError:
-        # Just fall back to defaults
         config = BuildConfig(
-            env_config={},
+            env_config=env_config,
             raw_config={},
             source_file='empty',
             source_position=0,

readthedocs/doc_builder/constants.py

@@ -33,6 +33,7 @@ DOCKER_SOCKET = getattr(
 )
 DOCKER_VERSION = getattr(settings, 'DOCKER_VERSION', 'auto')
 DOCKER_IMAGE = getattr(settings, 'DOCKER_IMAGE', 'readthedocs/build:2.0')
+DOCKER_BUILD_IMAGES = getattr(settings, 'DOCKER_BUILD_IMAGES', {})
 DOCKER_LIMITS = {'memory': '200m', 'time': 600}
 DOCKER_LIMITS.update(getattr(settings, 'DOCKER_LIMITS', {}))
 

readthedocs/rtd_tests/tests/test_config_wrapper.py

@@ -46,6 +46,54 @@ class LoadConfigTests(TestCase):
                            install_project=False, requirements_file='urls.py')
         self.version = get(Version, project=self.project)
 
+    def test_python_supported_versions_default_image_1_0(self, load_config):
+        load_config.side_effect = create_load()
+        self.project.container_image = 'readthedocs/build:1.0'
+        self.project.save()
+        config = load_yaml_config(self.version)
+        self.assertEqual(load_config.call_count, 1)
+        load_config.assert_has_calls([
+            mock.call(path=mock.ANY, env_config={
+                'python': {'supported_versions': [2, 2.7, 3, 3.4]},
+                'type': 'sphinx',
+                'output_base': '',
+                'name': mock.ANY
+            }),
+        ])
+        self.assertEqual(config.python_version, 2)
+
+    def test_python_supported_versions_image_2_0(self, load_config):
+        load_config.side_effect = create_load()
+        self.project.container_image = 'readthedocs/build:2.0'
+        self.project.save()
+        config = load_yaml_config(self.version)
+        self.assertEqual(load_config.call_count, 1)
+        load_config.assert_has_calls([
+            mock.call(path=mock.ANY, env_config={
+                'python': {'supported_versions': [2, 2.7, 3, 3.5]},
+                'type': 'sphinx',
+                'output_base': '',
+                'name': mock.ANY
+            }),
+        ])
+        self.assertEqual(config.python_version, 2)
+
+    def test_python_supported_versions_image_latest(self, load_config):
+        load_config.side_effect = create_load()
+        self.project.container_image = 'readthedocs/build:latest'
+        self.project.save()
+        config = load_yaml_config(self.version)
+        self.assertEqual(load_config.call_count, 1)
+        load_config.assert_has_calls([
+            mock.call(path=mock.ANY, env_config={
+                'python': {'supported_versions': [2, 2.7, 3, 3.3, 3.4, 3.5, 3.6]},
+                'type': 'sphinx',
+                'output_base': '',
+                'name': mock.ANY
+            }),
+        ])
+        self.assertEqual(config.python_version, 2)
+
     def test_python_default_version(self, load_config):
         load_config.side_effect = create_load()
         config = load_yaml_config(self.version)