Get edx-platform unit tests to run

We manage to get unit tests to run in a dedicated openedx-test container. Only
35 tests are failing (out of 17k). I suspect these tests are also failing in
the devstack.

CHANGELOG.md

@@ -4,6 +4,8 @@ Note: Breaking changes between versions are indicated by "💥".
 
 ## Unreleased
 
+- [Feature] Add a `tutor images build --target=...` argument for [multi-stage Docker builds](https://docs.docker.com/develop/develop-images/multistage-build/).
+- [Feature] Create a test version of the openedx-dev Docker image for running edx-platform unit tests.
 - [Security] Apply security patch [26112](https://github.com/edx/edx-platform/pull/26112)
 - [Bugfix] Fix `local exec` command which crashed with a `AttributeError`.
 

docs/dev.rst

@@ -236,3 +236,35 @@ You should then specify the settings to use on the host::
 From then on, all ``dev`` commands will use the ``mysettings`` module. For instance::
 
     tutor dev runserver lms
+
+Running edx-platform unit tests
+-------------------------------
+
+It's possible to run the full set of unit tests that ship with `edx-platform <https://github.com/edx/edx-platform/>`__. To do so, you should first build the "test" target of the "openedx-dev" Docker image::
+
+    tutor images build --target=test openedx-dev
+
+.. warning::
+    Don't forget to re-build the development image afterwards if you'd like to run ``dev`` commands again! To do so, run ``tutor images build openedx-dev`` after you are done testing.
+
+Then, run unit tests with ``pytest`` commands::
+
+    # Run a test container
+    tutor dev run lms bash
+
+    # Run tests on common apps
+    unset DJANGO_SETTINGS_MODULE
+    export EDXAPP_TEST_MONGO_HOST=mongodb
+    pytest common
+    pytest openedx
+
+    # Run tests on LMS
+    export DJANGO_SETTINGS_MODULE=lms.envs.tutor.test
+    pytest lms
+
+    # Run tests on CMS
+    export DJANGO_SETTINGS_MODULE=cms.envs.tutor.test
+    pytest cms
+
+.. note::
+    Getting all edx-platform unit tests to pass on Tutor is currently a work-in-progress. Some unit tests are still failing. If you manage to fix some of these, please report your findings in the `Tutor forums <https://discuss.overhang.io>`__.

tutor/commands/images.py

@@ -45,8 +45,12 @@ def images_command():
     multiple=True,
     help="Set a custom host-to-IP mapping (host:ip).",
 )
+@click.option(
+    "--target",
+    help="Set the target build stage to build.",
+)
 @click.pass_obj
-def build(context, image_names, no_cache, build_args, add_hosts):
+def build(context, image_names, no_cache, build_args, add_hosts, target):
     config = tutor_config.load(context.root)
     command_args = []
     if no_cache:
@@ -55,6 +59,8 @@ def build(context, image_names, no_cache, build_args, add_hosts):
         command_args += ["--build-arg", build_arg]
     for add_host in add_hosts:
         command_args += ["--add-host", add_host]
+    if target:
+        command_args += ["--target", target]
     for image in image_names:
         build_image(context.root, config, image, *command_args)
 

tutor/templates/apps/openedx/settings/cms/test.py

@@ -0,0 +1 @@
+{% include "apps/openedx/settings/partials/common_test.py" %}

tutor/templates/apps/openedx/settings/lms/test.py

@@ -0,0 +1 @@
+{% include "apps/openedx/settings/partials/common_test.py" %}

tutor/templates/apps/openedx/settings/partials/common_test.py

@@ -0,0 +1,9 @@
+# TODO clean this up
+import os
+os.environ["EDXAPP_TEST_MONGO_HOST"] = "mongodb"
+
+from ..test import *
+
+# Fix MongoDb connection credentials
+DOC_STORE_CONFIG["user"] = None
+DOC_STORE_CONFIG["password"] = None

tutor/templates/build/openedx-dev/Dockerfile

@@ -1,4 +1,4 @@
-FROM {{ DOCKER_IMAGE_OPENEDX }}
+FROM {{ DOCKER_IMAGE_OPENEDX }} as base
 MAINTAINER Overhang.io <contact@overhang.io>
 
 # Install useful system requirements
@@ -28,5 +28,15 @@ RUN chmod a+x /openedx/bin/*
 ARG USERID=1000
 RUN create-user.sh $USERID
 
+######## Test image
+FROM base as test
+
+# Run all tests by default
+ENTRYPOINT ["docker-entrypoint-test.sh"]
+CMD pytest
+
+######## Development image
+FROM base as dev
+
 # Default django settings
 ENV SETTINGS tutor.development

tutor/templates/build/openedx-dev/bin/docker-entrypoint-test.sh

@@ -0,0 +1,8 @@
+#!/bin/sh -e
+
+# Unset service variantm, which otherwise causes some unit tests to fail
+unset SERVICE_VARIANT
+# This variable should be set adequately depending on the set of unit tests to run
+unset DJANGO_SETTINGS_MODULE
+
+exec "$@"

tutor/templates/dev/docker-compose.yml

@@ -3,8 +3,6 @@ version: "3.7"
 x-openedx-service:
   &openedx-service
   image: {{ DOCKER_IMAGE_OPENEDX_DEV }}
-  environment:
-    SETTINGS: ${TUTOR_EDX_PLATFORM_SETTINGS:-tutor.development}
   volumes:
     # Settings & config
     - ../apps/openedx/settings/lms/:/openedx/edx-platform/lms/envs/tutor/:ro