Dynamic messages

Great work with this module!

There is one thing missing, though: I would like to have dynamic messages for my errors when possible. To make that happen, message option could be received as function.

As you don’t expose ApolloError, things are harder they it should to increment your lib. Here is a work around I’m using to achieve it:

const createDynamicError = (name, opts = {}) => class CustomError {
  constructor (...args) {
    const config = typeof opts === 'string' || typeof opts === 'function'
      ? { message: opts }
      : opts

    if (typeof config.message === 'function') {
      config.message = config.message(...args)
    }

    return new (createError(name, config))(...args.slice(-1))
  }
}

You could then use it like so:

const UserNotFoundError = createCustomError('UserNotFoundError', {
  message: username => `User ${username} not found`
})

// Or, shurtcuted:
const UserNotFoundError = createCustomError('UserNotFoundError', username => `User ${username} not found`)

// And use it like that:
new UserNotFoundError('lucas')

// Or, with data as in the original createError:
new UserNotFoundError('lucas', { data: { foo: 'bar' } })

Hope it helps someone 😉

[thebigredgeek]

I’m closing this for now, since there doesn’t seem to be any interest in moving forward

[thebigredgeek]

@scf4 I mostly agree, but I also don’t feel overly pained about adding this if enough people want it. I personally render the messages directly in the client, because my current app doesn’t have to worry about i18n etc. That said, there is nothing stopping anyone from using a factory function to return errors with dynamic messages without baking any new functionality into the lib.