Fix setting of upper_constraints fact

The pip_constraint_update filter overrides pip versions from the second
provided list to the first. Update the 'Set upper constraints' task so
that upper-constraints correctly take priority over the local
requirements packages versions.

A test has been included to validate that the role built package
constraints file is correctly applying the upper-constraints from the
openstack requirements repo.

Closes-Bug: 1605846
Change-Id: I53864a34f3ba56a84ed658fa3952aba3c509e0b1

releasenotes/notes/repo-build-fix-upper-constraints-9e24c56520538df2.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - The ``repo_build`` role now correctly applies OpenStack requirements
+    upper-constraints when building Python wheels. This resolves
+    https://bugs.launchpad.net/openstack-ansible/+bug/1605846

tasks/repo_set_facts.yml

@@ -49,7 +49,7 @@
 
 - name: Set upper constraints
   set_fact:
-    upper_constraints: "{{ _upper_constraints | pip_constraint_update(local_requirement_normalized) }}"
+    upper_constraints: "{{ local_requirement_normalized | pip_constraint_update(_upper_constraints) }}"
   when: slurp_upper_constraints | success
   tags:
     - repo-set-constraints

tests/test-repo-build.yml

@@ -52,5 +52,31 @@
     - name: Ensure that the nova venv is NOT present
       assert:
         that: "'nova-{{ repo_build_release_tag }}.tgz' not in venv_folder_content.stdout"
+    - name: Slurp upper constraints
+      slurp:
+        src: "{{ repo_build_git_dir }}/requirements/upper-constraints.txt"
+      register: slurp_upper_constraints
+    - name: Slurp requirements constraints
+      slurp:
+        src: "{{ repo_build_release_path }}/{{ repo_build_release_tag }}/requirements_constraints.txt"
+      register: slurp_requirements_constraints
+    - name: Set fact for requirements constraints content
+      set_fact:
+         requirements_constraints_content: "{{ slurp_requirements_constraints.content | b64decode }}"
+    - name: Set fact for upper constraints dictionary
+      set_fact:
+        upper_constraints_dict: >
+          {%- set constraints = {} %}
+          {%- for package in slurp_upper_constraints.content | b64decode | splitlines %}
+          {%-    set name = package | regex_replace('===.*$','') %}
+          {%-    set version = package | regex_replace('^.*===','') %}
+          {%-    set _ = constraints.update({name:version}) %}
+          {%- endfor %}
+          {{- constraints -}}
+    - name: Ensure that requirements constraints is applying upper constraints
+      assert:
+       that: requirements_constraints_content.find( "{{ item.key }}<={{item.value}}" ) != -1
+      with_dict: upper_constraints_dict
+      when: requirements_constraints_content.find(item.key) != -1
   vars_files:
     - test-vars.yml