Use host_vars for wheel builds

No need to use magic names since we now have host_vars, instead set
wheel_python explicitly.

Remove TODO comment.

Change-Id: I5051a32d843b106b013b94d57fd24b63896b741a

playbooks/wheel/post-base.yaml

@@ -1,9 +1,5 @@
 - hosts: all
   tasks:
-    - name: Select python version of build
-      set_fact:
-        wheel_python: "python{{ inventory_hostname[-1] }}"
-
     - name: Ensure build logs directory exists
       file:
         path: "{{ zuul.executor.log_root }}/{{ wheel_python }}"

roles/build-wheels/tasks/main.yaml

@@ -1,7 +1,3 @@
-- name: Select python version to build
-  set_fact:
-    wheel_python: "python{{ inventory_hostname[-1] }}"
-
 - name: Ensure wheel dir exists
   file:
     group: zuul

zuul.d/jobs.yaml

@@ -958,13 +958,12 @@
     description: |
       Build CentOS 7 wheels for OpenStaci CI mirrors.
     nodeset:
-      # NOTE: The python2 and python3 suffix are important, they select the
-      # version of python to build in each job. (we pull the last character of
-      # the inventory_hostname)
-      # TODO(mordred): Replace the suffix with host_vars once we have them.
       nodes:
         - name: wheel-mirror-centos-7-python2
           label: centos-7
+    host_vars:
+      wheel-mirror-ubuntu-centos-7-python2:
+        wheel_python: python2
 
 - job:
     name: publish-wheel-mirror-centos-7
@@ -983,15 +982,16 @@
     description: |
       Build Ubuntu Trusty wheels for OpenStaci CI mirrors.
     nodeset:
-      # NOTE: The python2 and python3 suffix are important, they select the
-      # version of python to build in each job. (we pull the last character of
-      # the inventory_hostname)
-      # TODO(mordred): Replace the suffix with host_vars once we have them.
       nodes:
         - name: wheel-mirror-ubuntu-trusty-python2
           label: ubuntu-trusty
         - name: wheel-mirror-ubuntu-trusty-python3
           label: ubuntu-trusty
+    host_vars:
+      wheel-mirror-ubuntu-trusty-python2:
+        wheel_python: python2
+      wheel-mirror-ubuntu-trusty-python3:
+        wheel_python: python3
 
 - job:
     name: publish-wheel-mirror-ubuntu-trusty
@@ -1010,15 +1010,16 @@
     description: |
       Build Ubuntu Xenial wheels for OpenStaci CI mirrors.
     nodeset:
-      # NOTE: The python2 and python3 suffix are important, they select the
-      # version of python to build in each job. (we pull the last character of
-      # the inventory_hostname)
-      # TODO(mordred): Replace the suffix with host_vars once we have them.
       nodes:
         - name: wheel-mirror-ubuntu-xenial-python2
           label: ubuntu-xenial
         - name: wheel-mirror-ubuntu-xenial-python3
           label: ubuntu-xenial
+    host_vars:
+      wheel-mirror-ubuntu-xenial-python2:
+        wheel_python: python2
+      wheel-mirror-ubuntu-xenial-python3:
+        wheel_python: python3
 
 - job:
     name: publish-wheel-mirror-ubuntu-xenial