On Wed, Aug 9, 2017 at 11:40 AM, Tom Bentley <t.j.bent...@gmail.com> wrote: > > There are responses with detailed error messages as well as the codes, > CreateTopicsResponse, {Describe|Alter}ConfigsResponse, and the responses > for managing ACLs for instance. To be honest, I assumed including a message > was the norm. In this case, however, I don't think there is any extra > detail to include beyond the error itself, so I've removed it from the KIP. >
We started sending back actual error messages when we introduced the Create Topic Policy as the errors are custom and much more helpful if a string can be sent back. In general, I think it would be better if we had an optional error message for all request types as error codes alone sometimes result in people having to check the broker logs. Examples that come to mind are Group Coordinator Not Available and Invalid Request. For the latter, we want to include what was invalid and it's not practical to have an error code for every possible validation error (this becomes more obvious once we start adding admin protocol APIs). Ismael