Changes for Ansible 2.4

Squashed changes:
   - Use 'inventory' instead of 'hostfile' in ansible.cfg.

     'hostfile' is deprecated.

   - Use 'os.environ.copy()' in zuul_return.py since this causes 2.4 to
     throw an exception now deep within module.exit_json().

Change-Id: I0a52c9e169a54d24a7b361010045fb10211418b7

playbooks/zuul-stream/templates/ansible.cfg.j2

@@ -1,5 +1,5 @@
 [defaults]
-hostfile = {{ ansible_user_dir }}/inventory.yaml
+inventory = {{ ansible_user_dir }}/inventory.yaml
 gathering = smart
 gather_subset = !all
 lookup_plugins = {{ ansible_user_dir }}/src/git.openstack.org/openstack-infra/zuul/zuul/ansible/lookup

tools/test-logs.sh

@@ -42,7 +42,7 @@ fi
 
 cat >$WORK_DIR/ansible.cfg <<EOF
 [defaults]
-hostfile = $INVENTORY
+inventory = $INVENTORY
 gathering = smart
 gather_subset = !all
 fact_caching = jsonfile

zuul/ansible/library/zuul_return.py

@@ -63,7 +63,7 @@ def main():
         path = os.path.join(os.environ['ZUUL_JOBDIR'], 'work',
                             'results.json')
     set_value(path, p['data'], p['file'])
-    module.exit_json(changed=True, e=os.environ)
+    module.exit_json(changed=True, e=os.environ.copy())
 
 from ansible.module_utils.basic import *  # noqa
 from ansible.module_utils.basic import AnsibleModule

zuul/executor/server.py

@@ -1185,7 +1185,7 @@ class AnsibleJob(object):
             callback_path = self.executor_server.callback_dir
         with open(jobdir_playbook.ansible_config, 'w') as config:
             config.write('[defaults]\n')
-            config.write('hostfile = %s\n' % self.jobdir.inventory)
+            config.write('inventory = %s\n' % self.jobdir.inventory)
             config.write('local_tmp = %s/local_tmp\n' %
                          self.jobdir.ansible_cache_root)
             config.write('retry_files_enabled = False\n')