Add index_links option to zuul manifest

This allows a deployer to indicate that they prefer the Zuul
dashboard to link to "dir/index.html" rather than just "/dir" when
displaying directory entries in the log browser.  This helps with
log storage systems which do not automatically serve index.html
files at directory urls.

Change-Id: I0444798c689667e51d8761a20b661f8a9b90323d

roles/generate-zuul-manifest/README.rst

@@ -26,3 +26,9 @@ display logs from a build.
    :default: zuul_manifest
 
    The artifact type to return to Zuul.
+
+.. zuul:rolevar:: generate_zuul_manifest_index_links
+   :default: False
+
+   If True, the Zuul dashboard will link to "index.html" for directory
+   entries; if False, it will link to the bare directory.

roles/generate-zuul-manifest/defaults/main.yaml

@@ -2,3 +2,4 @@ generate_zuul_manifest_root: "{{ zuul.executor.log_root }}"
 generate_zuul_manifest_filename: "zuul-manifest.json"
 generate_zuul_manifest_output: "{{ zuul.executor.log_root }}/{{ generate_zuul_manifest_filename }}"
 generate_zuul_manifest_type: "zuul_manifest"
+generate_zuul_manifest_index_links: False

roles/generate-zuul-manifest/library/generate_manifest.py

@@ -87,10 +87,11 @@ def walk(root, original_root=None):
     return data
 
 
-def run(root_path, output):
+def run(root_path, output, index_links):
     data = walk(root_path, root_path)
     with open(output, 'w') as f:
-        f.write(json.dumps({'tree': data}))
+        f.write(json.dumps({'tree': data,
+                            'index_links': index_links}))
 
 
 def ansible_main():
@@ -98,11 +99,12 @@ def ansible_main():
         argument_spec=dict(
             root=dict(type='path'),
             output=dict(type='path'),
+            index_links=dict(type='bool', default=False),
         )
     )
 
     p = module.params
-    run(p.get('root'), p.get('output'))
+    run(p.get('root'), p.get('output'), p.get('index_links'))
 
     module.exit_json(changed=True)
 
@@ -117,13 +119,15 @@ def cli_main():
                         help='Root of upload directory')
     parser.add_argument('output',
                         help='Output file path')
+    parser.add_argument('index_links', action='store_true',
+                        help='Link to index.html instead of dirs')
 
     args = parser.parse_args()
 
     if args.verbose:
         logging.basicConfig(level=logging.DEBUG)
 
-    run(args.root, args.output)
+    run(args.root, args.output, args.index_links)
 
 
 if __name__ == '__main__':

roles/generate-zuul-manifest/tasks/main.yaml

@@ -10,5 +10,6 @@
         artifacts:
           - name: Zuul Manifest
             url: "{{ generate_zuul_manifest_filename }}"
+            index_links: "{{ generate_zuul_manifest_index_links }}"
             metadata:
               type: "{{ generate_zuul_manifest_type }}"