Clean up developer mode logic

Fixes the ability to deploy a venv in cases where:
1) developer_mode is not enabled
2) A cached venv is not downloaded from the repo server

Additional cleanup to the developer_mode venv deployment
logic is implemented by adding a *_venv_download var
which is used to decouple developer_mode from the
cached venv extraction process so that a deployer
can force venv builds in-place (disable cached
venv usage) without enabling developer mode
constraints.

Change-Id: I3e8d45aae6dbfb7fc3627f3dfb7e7352cf7b426a

defaults/main.yml

@@ -44,6 +44,9 @@ designate_bin: "/openstack/venvs/designate-{{ designate_venv_tag }}/bin"
 #  designate_etc_dir: "/usr/local/etc/designate"
 designate_etc_dir: "{{ designate_bin | dirname }}/etc/designate"
 
+# venv_download, even when true, will use the fallback method of building the
+# venv from scratch if the venv download fails.
+designate_venv_download: "{{ not designate_developer_mode | bool }}"
 # URL of the pre-built virtualenv
 designate_venv_download_url: http://127.0.0.1/venvs/untagged/ubuntu/designate.tgz
 
@@ -151,4 +154,3 @@ designate_policy_overrides: {}
 designate_designate_conf_overrides: {}
 designate_api_paste_ini_overrides: {}
 designate_rootwrap_conf_overrides: {}
-

tasks/designate_install.yml

@@ -44,14 +44,13 @@
     dest: "/var/cache/{{ designate_venv_download_url | basename }}"
     checksum: "sha1:{{ lookup('url', designate_venv_download_url | replace('tgz', 'checksum')) }}"
   register: designate_get_venv
-  when: not designate_developer_mode | bool
+  when: designate_venv_download | bool
 
 - name: Remove existing venv
   file:
     path: "{{ designate_bin | dirname }}"
     state: absent
-  when:
-    - designate_get_venv | changed
+  when: designate_get_venv | changed
 
 - name: Create designate venv dir
   file:
@@ -59,18 +58,14 @@
     state: directory
     mode: "0755"
   register: designate_venv_dir
-  when:
-    - not designate_developer_mode | bool
-    - designate_get_venv | changed
+  when: designate_get_venv | changed
 
 - name: Unarchive pre-built venv
   unarchive:
     src: "/var/cache/{{ designate_venv_download_url | basename }}"
     dest: "{{ designate_bin | dirname }}"
     copy: "no"
-  when:
-    - not designate_developer_mode | bool
-    - designate_get_venv | changed or designate_venv_dir | changed
+  when: designate_get_venv | changed
   notify:
     - Restart designate services
 
@@ -88,13 +83,11 @@
   until: install_packages|success
   retries: 5
   delay: 2
-  when: designate_developer_mode | bool
+  when: designate_get_venv | failed or designate_get_venv | skipped
   notify:
     - Restart designate services
 
 - name: Update virtualenv path
   command: >
     virtualenv-tools --update-path=auto --reinitialize {{ designate_bin | dirname }}
-  when:
-    - not designate_developer_mode | bool
-    - designate_get_venv | changed or designate_venv_dir | changed
+  when: designate_get_venv | changed