wsk: return 200 whenever we have a response from the app

We were returning the same status code as we got from DEEPaaS. This
makes OpenWhisk fail, since OpenWisk takes this status and returns an
unexpected failure. Now we always return 200 if we got a response from
the API (regardless of a success or not), 500 otherwise

Author: alvarolopez

deepaas/openwhisk/handle.py

@@ -125,7 +125,7 @@ async def invoke(app, request, args):
     else:
         body = base64.b64encode(response.text)
 
-    return response.status, {
+    return {
         'headers': dict(response.headers),
         'statusCode': response.status,
         'body': body

deepaas/openwhisk/proxy.py

@@ -86,10 +86,12 @@ async def run(request):
             return error_bad_request()
 
     try:
-        status, result = await handle.invoke(APP, req_clone, args)
-        response = web.json_response(result, status=status)
+        result = await handle.invoke(APP, req_clone, args)
+        # NOTE(aloga): we got a response, even if it is a failure, therefore we
+        # return a 200 error
+        response = web.json_response(result, status=200)
     except Exception as e:
-        raise e
+        # NOTE(aloga): something weird happened server-side, return a 500.
         response = web.json_response(
             {'error': 'Internal error. {}'.format(e)},
             status=500