Ever tried to create custom error types in Node.js and wished it should be this simple?
var MyError = Error.extend('MyError');
throw MyError('wow')
npm install extend-error
and in your app.js, just require('extend-error'). It will provide you an extend() method for the Error type.
- extend() takes two arguments : subTypeName & errorCode [optional]
- it returns the newly created error type
something useful
var AppError = Error.extend('AppError', 500);
var ClientError = Error.extend('ClientError', 400);
extend ClientError further for specific http types
var HttpNotFound = ClientError.extend('HttpNotFoundError', 404);
var HttpUnauthorized = ClientError.extend('HttpUnauthorized', 401);
throw new AppError('unable to connect db due to error: ' err);
throw new ClientError({'message':'required field missing', field: 'email'})
throw new HttpNotFound('no post found with id: ' id);
throw new HttpNotFound({'message': 'no such post', 'id': id});
throw ClientError('bad request');
throw an error in controller
var err = HttpNotFound('user profile not found');
throw err;
(or)
callback(err)
handle it easily in global error handler (in case of express.js error middleware)
if (err instanceof ClientError) {
//send out the actual message
res.send(err.code, err.message);
} else {
//send out a generic message
res.send(500, 'oops! something went wrong');
log.error(err);
}