Learning Contexts, New XBlock Runtime, Blockstore API Client + Content Libraries

https://github.com/edx/edx-platform/pull/20645

This introduces:
* A new XBlock runtime that can read and write XBlocks that are persisted using
  Blockstore instead of Modulestore. The new runtime is currently isolated so
  that it can be tested without risk to the current courseware/runtime.
* Content Libraries v2, which store XBlocks in Blockstore not modulestore
* An API Client for Blockstore
* "Learning Context" plugin API. A learning context is a more abstract concept
  than a course; it's a collection of XBlocks that serves some learning purpose.

cms/envs/common.py

@@ -1201,6 +1201,9 @@ INSTALLED_APPS = [
     'openedx.core.djangoapps.course_groups',  # not used in cms (yet), but tests run
     'xblock_config.apps.XBlockConfig',
 
+    # New (Blockstore-based) XBlock runtime
+    'openedx.core.djangoapps.xblock.apps.StudioXBlockAppConfig',
+
     # Maintenance tools
     'maintenance',
     'openedx.core.djangoapps.util.apps.UtilConfig',
@@ -1683,6 +1686,13 @@ DATABASE_ROUTERS = [
 ############################ Cache Configuration ###############################
 
 CACHES = {
+    'blockstore': {
+        'KEY_PREFIX': 'blockstore',
+        'KEY_FUNCTION': 'util.memcache.safe_key',
+        'LOCATION': ['localhost:11211'],
+        'TIMEOUT': '86400',  # This data should be long-lived for performance, BundleCache handles invalidation
+        'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
+    },
     'course_structure_cache': {
         'KEY_PREFIX': 'course_structure',
         'KEY_FUNCTION': 'util.memcache.safe_key',

cms/envs/devstack.py

@@ -181,6 +181,9 @@ IDA_LOGOUT_URI_LIST = [
     'http://localhost:18150/logout/',  # credentials
 ]
 
+############################### BLOCKSTORE #####################################
+BLOCKSTORE_API_URL = "http://edx.devstack.blockstore:18250/api/v1/"
+
 #####################################################################
 
 # pylint: disable=wrong-import-order, wrong-import-position

cms/envs/production.py

@@ -404,6 +404,12 @@ XBLOCK_FIELD_DATA_WRAPPERS = ENV_TOKENS.get(
 
 CONTENTSTORE = AUTH_TOKENS['CONTENTSTORE']
 DOC_STORE_CONFIG = AUTH_TOKENS['DOC_STORE_CONFIG']
+
+############################### BLOCKSTORE #####################################
+BLOCKSTORE_API_URL = ENV_TOKENS.get('BLOCKSTORE_API_URL', None)  # e.g. "https://blockstore.example.com/api/v1/"
+# Configure an API auth token at (blockstore URL)/admin/authtoken/token/
+BLOCKSTORE_API_AUTH_TOKEN = AUTH_TOKENS.get('BLOCKSTORE_API_AUTH_TOKEN', None)
+
 # Datadog for events!
 DATADOG = AUTH_TOKENS.get("DATADOG", {})
 DATADOG.update(ENV_TOKENS.get("DATADOG", {}))

cms/envs/test.py

@@ -182,6 +182,12 @@ CACHES = {
     },
 }
 
+############################### BLOCKSTORE #####################################
+# Blockstore tests
+RUN_BLOCKSTORE_TESTS = os.environ.get('EDXAPP_RUN_BLOCKSTORE_TESTS', 'no').lower() in ('true', 'yes', '1')
+BLOCKSTORE_API_URL = os.environ.get('EDXAPP_BLOCKSTORE_API_URL', "http://edx.devstack.blockstore-test:18251/api/v1/")
+BLOCKSTORE_API_AUTH_TOKEN = os.environ.get('EDXAPP_BLOCKSTORE_API_AUTH_TOKEN', 'edxapp-test-key')
+
 ################################# CELERY ######################################
 
 CELERY_ALWAYS_EAGER = True

cms/urls.py

@@ -56,6 +56,7 @@ urlpatterns = [
         contentstore.views.component_handler, name='component_handler'),
     url(r'^xblock/resource/(?P<block_type>[^/]*)/(?P<uri>.*)$',
         openedx.core.djangoapps.common_views.xblock.xblock_resource, name='xblock_resource_url'),
+    url(r'', include('openedx.core.djangoapps.xblock.rest_api.urls', namespace='xblock_api')),
     url(r'^not_found$', contentstore.views.not_found, name='not_found'),
     url(r'^server_error$', contentstore.views.server_error, name='server_error'),
     url(r'^organizations$', OrganizationListView.as_view(), name='organizations'),