Add jsonp decorator

CLOSE T110

source: http://flask.pocoo.org/snippets/79/

swh/web/ui/controller.py

@@ -13,6 +13,7 @@ from flask import make_response
 from swh.core.hashutil import ALGORITHMS
 from swh.web.ui.main import app
 from swh.web.ui import service, query
+from swh.web.ui.decorators import jsonp
 
 
 hash_filter_keys = ALGORITHMS
@@ -287,6 +288,7 @@ def revision_at_origin(timestamp, origin_type, origin_url):
 
 
 @app.route('/api/1/stat/counters')
+@jsonp
 def api_stats():
     """Return statistics as a JSON object"""
     return jsonify(service.stat_counters())

swh/web/ui/decorators.py

+# Copyright (C) 2015  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU Affero General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+
+from functools import wraps
+from flask import request, current_app
+
+
+def jsonp(func):
+    """Wraps JSONified output for JSONP requests."""
+    @wraps(func)
+    def decorated_function(*args, **kwargs):
+        callback = request.args.get('callback', False)
+        if callback:
+            res = func(*args, **kwargs)
+            if hasattr(res, 'data'):  # for a response object, data
+                data = res.data
+                if isinstance(data, bytes):  # we're dealing in utf-8 bytes
+                    data = data.decode('utf-8')
+                else:
+                    data = str(data)
+            else:  # fallback case...
+                data = str(res)
+
+            content = ''.join([str(callback), '(', data, ')'])
+            return current_app.response_class(
+                content,
+                mimetype='application/javascript')
+        return func(*args, **kwargs)
+    return decorated_function