error-handling-options-nestjs-prisma.ts

// https://www.apollographql.com/docs/apollo-server/data/errors/#unauthenticated

// Using types and unions
// https://blog.logrocket.com/handling-graphql-errors-like-a-champ-with-unions-and-interfaces/

// Wrap mutation with result{user, errors}
// https://stackoverflow.com/a/55532706

// UserInputError
// ValidationError
// ForbiddenError

// #1
throw new UserInputError('User with this slug already exists!')

// #2 
throw new ApolloError('My error message', 'MY_ERROR_CODE', myCustomExtensions);

// #3
import { ApolloError } from 'apollo-server-errors';

export class MyError extends ApolloError {
  constructor(message: string) {
    super(message, 'MY_ERROR_CODE');

    Object.defineProperty(this, 'name', { value: 'MyError' });
  }
}

throw new MyError('My error message')

// Pipes #1
@UsePipes(new JoiValidationPipe(createCatSchema))
async create(@Body() createCatDto: CreateCatDto) {
  this.catsService.create(createCatDto);
}

// Pipes #2
@Mutation(returns => Group)
async createGroup(
  @Args('group', new ValidationPipe())
  input: CreateGroupInput,
)


// catch-all setup for ApolloServer
formatError(err) {
  if (err.originalError instanceof AuthenticationError) {
    return new Error('Different authentication error message!');
  }
},
  
  
// ONLY CATCH SPECIFIC ERRORS AND RE-THROW OTHERS
try {
  myroutine(); // There's a couple of errors thrown here
} catch (e) {
  if (e instanceof TypeError) {
    // A TypeError
  } else if (e instanceof RangeError) {
    // Handle the RangeError
  } else if (e instanceof EvalError) {
    // you guessed it: EvalError
  } else if (typeof e === "string") {
    // The error is a string
  } else if (axios.isAxiosError(e)) {
    // axios does an error check for us!
  } else {
    // everything else  
    logMyErrors(e);
  }
}