Cache downloaded roles & collections

Populate the cache the first time the job is run for a revision
that needs them, and for future runs for that revision just
copy it into the private directory.

Delete the cache on project deletion.

awx/playbooks/project_update.yml

@@ -1,6 +1,7 @@
 ---
 # The following variables will be set by the runner of this playbook:
 # project_path: PROJECTS_DIR/_local_path_
+# project_cache: CACHE_DIR/.__awx_cache/_local_path_
 # scm_url: https://server/repo
 # insights_url: Insights service URL (from configuration)
 # scm_branch: branch/tag/revision (HEAD if unset)
@@ -116,13 +117,17 @@
   tasks:
 
     - block:
+        - name: set content cache location
+          set_fact:
+            cache_dir: "{{ project_cache }}/{{ scm_branch }}"
+
         - name: detect requirements.yml
           stat:
             path: '{{project_path|quote}}/roles/requirements.yml'
           register: doesRequirementsExist
 
         - name: fetch galaxy roles from requirements.yml
-          command: ansible-galaxy role install -r roles/requirements.yml -p {{roles_destination|quote}}{{ ' -' + 'v' * ansible_verbosity if ansible_verbosity else '' }}
+          command: ansible-galaxy role install -r roles/requirements.yml -p {{ cache_dir }}/requirements_roles {{ ' -' + 'v' * ansible_verbosity if ansible_verbosity else '' }}
           args:
             chdir: "{{project_path|quote}}"
           register: galaxy_result
@@ -132,18 +137,27 @@
             ANSIBLE_FORCE_COLOR: false
             GIT_SSH_COMMAND: "ssh -o StrictHostKeyChecking=no"
 
+        - name: populate job directory with needed roles
+          synchronize:
+            src: "{{ cache_dir }}/requirements_roles"
+            dest: "{{ roles_destination }}"
+
       when: roles_enabled|bool
       tags:
         - install_roles
 
     - block:
+        - name: set content cache location
+          set_fact:
+            cache_dir: "{{ project_cache }}/{{ scm_branch }}"
+
         - name: detect collections/requirements.yml
           stat:
             path: '{{project_path|quote}}/collections/requirements.yml'
           register: doesCollectionRequirementsExist
 
         - name: fetch galaxy collections from collections/requirements.yml
-          command: ansible-galaxy collection install -r collections/requirements.yml -p {{collections_destination|quote}}{{ ' -' + 'v' * ansible_verbosity if ansible_verbosity else '' }}
+          command: ansible-galaxy collection install -r collections/requirements.yml -p {{ cache_dir }}/requirements_collections {{ ' -' + 'v' * ansible_verbosity if ansible_verbosity else '' }}
           args:
             chdir: "{{project_path|quote}}"
           register: galaxy_collection_result
@@ -151,9 +165,14 @@
           changed_when: "'Installing ' in galaxy_collection_result.stdout"
           environment:
             ANSIBLE_FORCE_COLOR: false
-            ANSIBLE_COLLECTIONS_PATHS: "{{ collections_destination }}"
+            ANSIBLE_COLLECTIONS_PATHS: "{{ cache_dir }}/requirements_collections"
             GIT_SSH_COMMAND: "ssh -o StrictHostKeyChecking=no"
 
+        - name: populate job directory with needed collections
+          synchronize:
+            src: "{{ cache_dir }}/requirements_collections"
+            dest: "{{ collections_destination }}"
+
       when:
         - "ansible_version.full is version_compare('2.8', '>=')"
         - collections_enabled|bool