fixed issue 1318, as_yaml, thanks Alan

gluon/serializers.py

@@ -19,6 +19,11 @@ except ImportError:
     except:
         import contrib.simplejson as json_parser    # fallback to pure-Python module
 
+have_yaml = True
+try:
+    import yaml
+except ImportError:
+    have_yaml = False
 
 def loads_json(o):
     # deserialize a json string
@@ -119,3 +124,14 @@ def rss(feed):
                            pubDate=entry.get('created_on', now)
                            ) for entry in feed.get('entries', [])])
     return rss.to_xml(encoding='utf-8')
+
+def yaml(data):
+    if have_yaml:
+        return yaml.dump(data)
+    else: raise ImportError("No YAML serializer available")
+
+def loads_yaml(data):
+    if have_yaml:
+        return yaml.load(data)
+    else: raise ImportError("No YAML serializer available")
+