diff --git a/endpoints/api/globalmessages.py b/endpoints/api/globalmessages.py
index 0ed868836..43ea58083 100644
--- a/endpoints/api/globalmessages.py
+++ b/endpoints/api/globalmessages.py
@@ -102,7 +102,10 @@ class GlobalUserMessages(ApiResource):
       abort(404)
 
     if SuperUserPermission().can():
-      model.create_message(request.get_json()['message'])
+      message_req = request.get_json()['message']
+      message = model.create_message(message_req['severity'], message_req['media_type'], message_req['content'])
+      if message is None:
+        abort(400)
       return make_response('', 201)
 
     abort(403)
diff --git a/endpoints/api/globalmessages_models_interface.py b/endpoints/api/globalmessages_models_interface.py
index b3b556ffc..679462c1d 100644
--- a/endpoints/api/globalmessages_models_interface.py
+++ b/endpoints/api/globalmessages_models_interface.py
@@ -23,17 +23,32 @@ class GlobalMessage(
 
 @add_metaclass(ABCMeta)
 class GlobalMessageDataInterface(object):
+  """
+  Data interface for globalmessages API
+  """
   
   @abstractmethod
   def get_all_messages(self):
-    pass
+    """
+    
+    Returns:
+    list(GlobalMessage)
+    """
   
   @abstractmethod
-  def create_message(self):
-    pass
+  def create_message(self, severity, media_type_name, content):
+    """
+    
+    Returns:
+    GlobalMessage or None
+    """
   
   @abstractmethod
-  def delete_message(self):
-    pass
+  def delete_message(self, uuid):
+    """
+    
+    Returns:
+    void
+    """
   
   
\ No newline at end of file
diff --git a/endpoints/api/globalmessages_models_pre_oci.py b/endpoints/api/globalmessages_models_pre_oci.py
index 9a91ee0e7..d9a623f1b 100644
--- a/endpoints/api/globalmessages_models_pre_oci.py
+++ b/endpoints/api/globalmessages_models_pre_oci.py
@@ -8,13 +8,21 @@ class GlobalMessagePreOCI(GlobalMessageDataInterface):
     messages = model.message.get_messages()
     return [self._message(m) for m in messages]
   
-  def create_message(self, content):
-    model.message.create([content])
+  def create_message(self, severity, media_type_name, content):
+    message = {
+      'severity': severity,
+      'media_type': media_type_name,
+      'content': content
+    }
+    messages = model.message.create([message])
+    return self._message(messages[0])
   
   def delete_message(self, uuid):
     model.message.delete_message([uuid])
   
   def _message(self, message_obj):
+    if message_obj is None:
+      return None
     return GlobalMessage(
       uuid=message_obj.uuid,
       content=message_obj.content,