README.md

graphql-middleware-error-handler

This is a generic GraphQL middleware to handle errors that happen in resolvers.

It can be used with any error logging service (e.g. Sentry, Bugsnag).

Usage

This example uses graphql-yoga but it should be compatible with any other library that supports graphql-middleware.

import { GraphQLServer } from 'graphql-yoga';
import { errorHandler } from 'graphql-middleware-error-handler';

const typeDefs = `
  type Query {
    info: String!
    error: String!
  }
`;

const resolvers = {
  Query: {
    hello: () => 'I am a GraphQL Server',
    error: () => {
      throw new Error('This was not supposed to happen');
    },
  },
};

const errorHandlerMiddleware = errorHandler({
  onError: (error, context) => {
    // send error anywhere
  },
  captureReturnedErrors: true,
  forwardErrors: false,
});

const server = GraphQLServer({
  typeDefs,
  resolvers,
  middlewares: [errorHandlerMiddleware],
});

server.start(() => 'Server running');

Options

onError

The only required option, the function that is called when an error occurs. It's called with the error as first argument, and the GraphQL context as the second.

captureReturnedErrors

Determines if a resolver returns an error instead of throwing one it should also be captured. Defaults to false.

forwardErrors

Determines if the error should be rethrown after is was captured by the middleware. Defaults to false.

License

This project is licensed under the MIT License.