Field resolution to error

[mmjd]

Hi

If in schema.js, I resolve userType to a graphqlError by throwing an exception, nothing is rendered at all and renderError of routes is not called.

I get the following error in browser:

[HMR] Waiting for update signal from WDS... asyncToGenerator.js:20 Uncaught (in promise) undefined step @ asyncToGenerator.js:20 (anonymous) @ asyncToGenerator.js:30 Promise rejected (async) settle @ asyncGenerator.js:71 resume @ asyncGenerator.js:57 (anonymous) @ asyncGenerator.js:51 Promise rejected (async) settle @ asyncGenerator.js:71 resume @ asyncGenerator.js:57 (anonymous) @ asyncGenerator.js:51 Promise rejected (async) onError @ QuerySubscription.js:66 (anonymous) @ RelayNetwork.js:76 Promise resolved (async) executeImpl @ execute.js:133 execute @ execute.js:102 Object.defineProperty.value @ graphql.js:78 graphqlImpl @ graphql.js:62 graphql @ graphql.js:50 fetchQuery @ createFetch.js:14 requestStream @ RelayNetwork.js:59 streamQuery @ RelayModernEnvironment.js:115 (anonymous) @ QuerySubscription.js:35 F @ _export.js:35 fetch @ QuerySubscription.js:30 (anonymous) @ Resolver.js:41 _callee$ @ Resolver.js:40 tryCatch @ runtime.js:65 invoke @ runtime.js:303 prototype.(anonymous function) @ runtime.js:117 resume @ asyncGenerator.js:44 (anonymous) @ asyncGenerator.js:37 F @ _export.js:35 send @ asyncGenerator.js:24 exports.default.AsyncGenerator.next @ asyncGenerator.js:105 _callee$ @ resolveRenderArgs.js:3 tryCatch @ runtime.js:65 invoke @ runtime.js:303 prototype.(anonymous function) @ runtime.js:117 resume @ asyncGenerator.js:44 (anonymous) @ asyncGenerator.js:37 F @ _export.js:35 send @ asyncGenerator.js:24 exports.default.AsyncGenerator.next @ asyncGenerator.js:105 _callee$ @ createBaseRouter.js:11 tryCatch @ runtime.js:65 invoke @ runtime.js:303 prototype.(anonymous function) @ runtime.js:117 step @ asyncToGenerator.js:17 (anonymous) @ asyncToGenerator.js:35 F @ _export.js:35 (anonymous) @ asyncToGenerator.js:14 resolveMatch @ createBaseRouter.js:11 componentDidMount @ createBaseRouter.js:58 (anonymous) @ ReactCompositeComponent.js:264 measureLifeCyclePerf @ ReactCompositeComponent.js:75 (anonymous) @ ReactCompositeComponent.js:263 notifyAll @ CallbackQueue.js:76 close @ ReactReconcileTransaction.js:80 closeAll @ Transaction.js:209 perform @ Transaction.js:156 batchedMountComponentIntoNode @ ReactMount.js:126 perform @ Transaction.js:143 batchedUpdates @ ReactDefaultBatchingStrategy.js:62 batchedUpdates @ ReactUpdates.js:97 _renderNewRootComponent @ ReactMount.js:319 _renderSubtreeIntoContainer @ ReactMount.js:401 render @ ReactMount.js:422 (anonymous) @ client.js:45 __webpack_require__ @ bootstrap 8dbbe51…:659 fn @ bootstrap 8dbbe51…:85 (anonymous) @ amd-options.js:2 __webpack_require__ @ bootstrap 8dbbe51…:659 module.exports @ bootstrap 8dbbe51…:708 (anonymous) @ bootstrap 8dbbe51…:708 client?dc71:41 [WDS] Hot Module Replacement enabled.

which is caused by QuerySubscriber --> fetch--> onError() --> reject()

graphql response is as follows:

response json: { errors: [ { message: 'this is my error message', locations: [Object], path: [Object] } ], data: { viewer: { id: 'VXNlcjptZQ==', todos: null, numTodos: 2, numCompletedTodos: 1 } } } response json: { errors: [ { message: 'this is my error message', locations: [Object], path: [Object] } ], data: { viewer: { todos: null, id: 'VXNlcjptZQ==', numTodos: 2, numCompletedTodos: 1 } } }

[taion]

For consistency with <QueryRenderer>, data fetching errors don't yield router-level errors unless you rethrow in prerender. Just handle error rendering in the render callback as with <QueryRenderer>.

[mmjd]

I added both route-level render and top-level renderError functions but in case of graphql error response, none of the methods are called with error argument. I see the following error in console:

Uncaught (in promise) undefined

I'am stuck for handling graphql errors from server:

{ errors: [ { message: 'my custom error message' } ] }

would you please make an advise?

[taion]

I took a closer look.

Per facebook/relay#1913, your network layer actually needs to throw if you get any errors from your back end.

Separately, https://github.com/4Catalyzer/found-relay/pull/38/files#diff-0c098dedebf1347f99e1bf83329ad9d2R65 fixes a typo that would cause rendering to fail entirely when queries have errors. That is fixed in the newest alpha: https://github.com/4Catalyzer/found-relay/releases/tag/v0.3.0-alpha.3.

[mmjd]

thank you very much for your help. now, when both data and error are not null, route-level render error is populated with error but when only error exists and data is null in response, the following error is raised in console:

Uncaught (in promise) Error: Objects are not valid as a React child (found: RelayNetwork: No data returned for operationroutes_TodoApp_Query`, got error(s):
global error message

See the error source property for more information.). If you meant to render a collection of children, use an array instead or wrap the object using createFragment(object) from the React add-ons. Check the render method of SnapshotRenderer.
at invariant (invariant.js:44)
at traverseAllChildrenImpl (traverseAllChildren.js:144)
at traverseAllChildrenImpl (traverseAllChildren.js:93)
at traverseAllChildren (traverseAllChildren.js:172)
at flattenChildren (flattenChildren.js:66)
at ReactDOMComponent._reconcilerUpdateChildren (ReactMultiChild.js:202)
at ReactDOMComponent._updateChildren (ReactMultiChild.js:310)
at ReactDOMComponent.updateChildren (ReactMultiChild.js:297)
at ReactDOMComponent._updateDOMChildren (ReactDOMComponent.js:942)
at ReactDOMComponent.updateComponent (ReactDOMComponent.js:760)
`
and renderError is not called. would you please have a look? thank you.

[taion]

You need to actually render something in render. Regardless, renderError will not be called unless you throw an HttpError in prerender.