tests: Do not always fetch the get-pip.py script during tests

Since we are testing the idempotence of this role, we shouldn't
fetch the get-pip.py script on every iteration so we set the variable
to 'false'. Moreover, we bump the PIP version to 9.0.3 since this is
what is currently being deployed on the hosts. Finally, get-pip.py
uses --force-reinstall by default which means that everything is being
reinstalled all the time and this breaks idempotence. We can fix that by
simply checking if a suitable version of PIP is installed and then use
it to do a proper upgrade.

Change-Id: I998182eca9851d2cc745930fc73ca37bfefd0951

tasks/install_source.yml

@@ -16,7 +16,7 @@
 - block:
     - name: Install PIP
       command: >
-        python /opt/get-pip.py {{ (pip_install_upper_constraints is defined) |
+        {{ pip_install_script.stdout }} {{ (pip_install_upper_constraints is defined) |
                                   ternary('--constraint ' ~ pip_install_upper_constraints | default(''), '') }}
                                {{ pip_source_install_options }}
                                {{ pip_get_pip_options }}

tasks/main.yml

@@ -34,9 +34,22 @@
   tags:
     - pip_install-install
 
+- name: Determine PIP installation script
+  shell: >
+    if [[ $(set -o pipefail; pip --version 2>/dev/null | awk '{print $2}' | cut -d. -f1) -ge 7 ]]; then
+        echo "$(which pip) install --upgrade"
+    else
+        echo "python /opt/get-pip.py"
+    fi
+  args:
+    executable: /bin/bash
+  register: pip_install_script
+  changed_when: False
+
 - include_tasks: "install_{{ pip_offline_install | ternary('offline', 'online') }}.yml"
   tags:
     - pip_install-install
+  when: pip_install_script.find('get-pip.py') != -1 # skip get-pip.py if a suitable pip is installed
 
 - include_tasks: install_source.yml
   tags:

tests/test.yml

@@ -17,8 +17,9 @@
   hosts: localhost
   connection: local
   vars:
+    pip_get_pip_force: no
     pip_packages:
-      - "pip==8.0.3"
+      - "pip==9.0.3"
     pip_install_upper_constraints: "http://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt"
   roles:
     - role: "pip_install"
@@ -44,4 +45,4 @@
         that:
           - "pip_dir.stat.isdir"
           - "pip_selfcheck_file.stat.exists"
-          - "pip_version.stdout | search('8.0.3')"
+          - "pip_version.stdout | search('9.0.3')"