Support externally hosted comprehensive themes

The old Stanford-style themes can be pulled in from an external Git
repo; no such provision was previously available for comprehensive
themes.

* Introduce two new configuration variables:
- EDXAPP_COMPREHENSIVE_THEME_SOURCE_REPO: Git repo for the
  comprehensive theme
- EDXAPP_COMPREHENSIVE_THEME_VERSION: Git branch, tag, or revision to
  check out from the repo

* Introduce a new task, "checkout comprehensive theme", doing the
equivalent of the previously existing "checkout theme" task. Check out
the theme repo to EDXAPP_COMPREHENSIVE_THEME_DIR. If
EDXAPP_COMPREHENSIVE_THEME_SOURCE_REPO is unset, continue to assume
that EDXAPP_COMPREHENSIVE_THEME_DIR already exists and is populated
with a comprehensive theme.

* Rename the "checkout theme" task to "checkout Stanford-style theme".

AUTHORS

@@ -51,3 +51,4 @@ Steven Burch <stv@stanford.edu>
 Dan Powell <dan@abakas.com>
 Omar Al-Ithawi <oithawi@qrf.org>
 David Adams<dcadams@stanford.edu>
+Florian Haas <florian@hastexo.com>

playbooks/roles/edxapp/defaults/main.yml

@@ -537,7 +537,14 @@ EDXAPP_PROCTORING_BACKEND_PROVIDER:
   options: {}
 
 # Comprehensive Theming
+# Full path to the comprehensive theme directory
 EDXAPP_COMPREHENSIVE_THEME_DIR: ""
+# Git repo for the comprehensive theme (if using a comprehensive theme
+# other than the ones bundled with edx/platform)
+EDXAPP_COMPREHENSIVE_THEME_SOURCE_REPO: ""
+# Git branch, tag, or revision to check out from
+# EDXAPP_COMPREHENSIVE_THEME_SOURCE_REPO
+EDXAPP_COMPREHENSIVE_THEME_VERSION: ""
 
 # SAML KEYS
 EDXAPP_SOCIAL_AUTH_SAML_SP_PRIVATE_KEY: ''

playbooks/roles/edxapp/tasks/deploy.yml

@@ -83,7 +83,7 @@
     - install
     - install:code
 
-- name: checkout theme
+- name: checkout Stanford-style theme
   git: >
     dest={{ edxapp_app_dir }}/themes/{{ edxapp_theme_name }}
     repo={{ edxapp_theme_source_repo }}
@@ -98,6 +98,21 @@
     - install
     - install:code
 
+- name: checkout comprehensive theme
+  git: >
+    dest={{ EDXAPP_COMPREHENSIVE_THEME_DIR }}
+    repo={{ EDXAPP_COMPREHENSIVE_THEME_SOURCE_REPO }}
+    version={{ EDXAPP_COMPREHENSIVE_THEME_VERSION }}
+    accept_hostkey=yes
+  when: EDXAPP_COMPREHENSIVE_THEME_SOURCE_REPO != ''
+  sudo_user: "{{ edxapp_user }}"
+  environment:
+    GIT_SSH: "{{ edxapp_git_ssh }}"
+  register: edxapp_theme_checkout
+  tags:
+    - install
+    - install:code
+
 - name: Stat each requirements file with Github URLs to ensure it exists
   stat: path="{{ item }}"
   with_items: "{{ edxapp_requirements_with_github_urls }}"