New tests and small fixes while comparing against the V2 spec

Fixes #391

endpoints/v2/tag.py

@@ -1,19 +1,48 @@
 # XXX This code is not yet ready to be run in production, and should remain disabled until such
 # XXX time as this notice is removed.
 
-from flask import jsonify
+from flask import jsonify, request, url_for
 
+from app import get_app_url
 from endpoints.v2 import v2_bp, require_repo_read
+from endpoints.v2.errors import NameUnknown
 from auth.jwt_auth import process_jwt_auth
 from endpoints.decorators import anon_protect
 from data import model
 
+def _add_pagination(query, url):
+  limit = request.args.get('n', None)
+  page = request.args.get('page', 1)
+
+  if limit is None:
+    return None, query
+
+  url = get_app_url() + url
+  query = query.paginate(page, limit)
+  link = url + '?n=%s&last=%s; rel="next"' % (limit, page + 1)
+  return link, query
+
+
 @v2_bp.route('/<namespace>/<repo_name>/tags/list', methods=['GET'])
 @process_jwt_auth
 @require_repo_read
 @anon_protect
 def list_all_tags(namespace, repo_name):
-  return jsonify({
+  repository = model.repository.get_repository(namespace, repo_name)
+  if repository is None:
+    raise NameUnknown()
+
+  query = model.tag.list_repository_tags(namespace, repo_name)
+
+  url = url_for('v2.list_all_tags', namespace=namespace, repo_name=repo_name)
+  link, query = _add_pagination(query, url)
+
+  response = jsonify({
     'name': '{0}/{1}'.format(namespace, repo_name),
-    'tags': [tag.name for tag in model.tag.list_repository_tags(namespace, repo_name)],
+    'tags': [tag.name for tag in query],
   })
+
+  if link is not None:
+    response.headers['Link'] = link
+
+  return response