Migrating to Apollo server v4; ValidationError

[alexbjorlig]

Hi there.

I was looking into upgrading our Apollo server, from v3 to v4. According to the docs here, it's mentioned that ValidationError is no more.

So my question is, how would you refactor this code from apollo server v3?

import { ValidationError } from 'apollo-server';

throw new ValidationError('some-error');

Our project uses the above pattern in 144 files 🤣

[glasser]

See this section:

You can replace this with

import { GraphQLError } from 'graphql';
import { ApolloServerErrorCode } from '@apollo/server/errors';
throw new GraphQLError("some error", {
  extensions: {
    code:  ApolloServerErrorCode.GRAPHQL_VALIDATION_FAILED',
  },
);

Or if you'd like, just define your own class:

import { GraphQLError } from 'graphql';
import { ApolloServerErrorCode } from '@apollo/server/errors';
class ValidationError extends GraphQLError {
  constructor(message: string) {
    super(message, { extensions: { code: ApolloServerErrorCode.GRAPHQL_VALIDATION_FAILED } });
  }
}

We wanted to move away from the exported error class approach because it led to people trying to do instanceof ValidationError checks which could run into trouble if you accidentally ended up with multiple copies of apollo-server-errors installed (which was more likely in AS3 with its many-package structure than in AS4 where most code is in @apollo/server).

[alexbjorlig]

This worked really well, I could do search and replace. Thanks 👍 Probably going to ask a couple of other questions, but very helpful!