Use upper-constraints file in developer mode

Last week, keystone was failing to install in developer mode due to us
not specifying upper constraints.  This was due to an upcapped version
of pysaml2 being installed which is causing problems.  This commit first
clones the requirements repo and then uses the upper constraints file
when installing packages.

Note that we only update pip_install_options when in developer mode if
the constraints aren't already set.  This is because in developer mode
you could have a container with multiple services running on it and the
pip_install_options fact would get updated when already set, resulting
in pip failing to install packages.

Change-Id: If2e7036d02a94bee67df12a610b0110434410777
Partial-Bug: #1553963

defaults/main.yml

@@ -25,6 +25,8 @@ cache_timeout: 600
 
 nova_git_repo: https://git.openstack.org/openstack/nova
 nova_git_install_branch: master
+nova_requirements_git_repo: https://git.openstack.org/openstack/requirements
+nova_requirements_git_install_branch: master
 nova_developer_mode: false
 nova_developer_constraints:
   - "git+{{ nova_git_repo }}@{{ nova_git_install_branch }}#egg=nova"

tasks/nova_install.yml

@@ -56,15 +56,30 @@
     - nova-install
     - nova-pip-packages
 
-- name: Set constraint file fact for developer mode
-  set_fact:
-    pip_install_options: "{{ pip_install_options|default('') }} --constraint /opt/developer-pip-constraints.txt"
+- name: Clone requirements git repository
+  git:
+    repo: "{{ nova_requirements_git_repo }}"
+    dest: "/opt/requirements"
+    clone: yes
+    update: yes
+    version: "{{ nova_requirements_git_install_branch }}"
   when:
     - nova_developer_mode | bool
   tags:
     - nova-install
     - nova-pip-packages
 
+- name: Add constraints to pip_install_options fact for developer mode
+  set_fact:
+    pip_install_options: "{{ pip_install_options|default('') }} --constraint /opt/developer-pip-constraints.txt --constraint /opt/requirements/upper-constraints.txt"
+  when:
+    - nova_developer_mode | bool
+    - "'/opt/developer-pip-constraints.txt' not in pip_install_options|default('')"
+    - "'/opt/requirements/upper-constraints.txt' not in pip_install_options|default('')"
+  tags:
+    - nova-install
+    - nova-pip-packages
+
 - name: Install requires pip packages
   pip:
     name: "{{ item }}"

tests/test.yml

@@ -201,6 +201,7 @@
     keystone_venv_tag: "testing"
     keystone_developer_mode: true
     keystone_git_install_branch: a55128044f763f5cfe2fdc57c738eaca97636448
+    keystone_requirements_git_install_branch: 332278d456e06870150835564342570ec9d5f5a0
     keystone_auth_admin_token: "SuperSecreteTestToken"
     keystone_auth_admin_password: "SuperSecretePassword"
     keystone_service_password: "secrete"
@@ -296,6 +297,7 @@
     nova_venv_tag: "testing"
     nova_developer_mode: true
     nova_git_install_branch: deb1ee440923b0b292f3536a2f8bda672c03984a
+    nova_requirements_git_install_branch: 332278d456e06870150835564342570ec9d5f5a0
     nova_service_password: "secrete"
     nova_container_mysql_password: "SuperSecrete"
     nova_api_container_mysql_password: "SuperSecrete"