Relay: No way to get an underlying GraphQL error from RelayMutationTransaction's onFailure

[LegNeato]

No way to get an underlying GraphQL error from RelayMutationTransaction's onFailure:

  doIt: Function = () => {
    Relay.Store.update(
      new CreateMyRelayMutation(), {
        onSuccess: this.onMutationSuccess,
        onFailure: this.onMutationFailure,
      },
    );
  };
  onMutationSuccess: Function = (response: CreateMyMutationResponse) => {
    // Do stuff.
  };
  onMutationFailure: Function = (transaction: RelayMutationTransaction) => {
    console.log(transaction.getError().message);
  };

The problem is transaction.getError() in the onFailure callback only gives me access to a Relay Error, which means I can't get at the underlying GraphQL Error:

Server request for mutation `MyComponent` failed for the following reasons:

1. Cannot get name.
   createMyInput!){createMy(input:$input_0){clientMuta
                             ^^^

GraphQL errors are likely more user friendly than the Relay errors. I think onFailure should get passed the underlying GraphQL errors somehow to let tools choose which (Relay or GraphQL) is important for their use-case.

[josephsavona]

Thanks for asking about this. Relay creates error objects with a source property that includes the original error information from the server, which can be accessed as transaction.getError().source. It's an object with all the error data returned from the server.

[LegNeato]

Ah sweet, that is exactly what I needed...guess I missed it. Thanks!

[shangxiao]

That's odd, I'm getting an object of type Response from my transaction.getError(). Any ideas on what I'm doing wrong? Running with the latest development snapshot.

[josephsavona]

@rapilabs are you using the default network layer? If yes, and the error property is not what's documented then it's a bug (and worth filing a new issue).

[mloncaric]

How would you show that message to the end user?
Components are updated only in case transaction was successful..

I was thinking about using redux for that, but.. that looks like an overkill.
(onFailure would dispatch an action, which would then in turn trigger the component update)

[wincent]

@mloncaric: You could use setState if you wanted to avoid involving any Redux/Flux actions.

[somit]

Using transaction.getError().source ..but should be included in docs...

[matart15]

@somit you saved me from writing a whole custom error handler.