Using pattern in subscription and knowing destination topic about graphql-redis-subscriptions

[davidyaha]

Hey @tomasAlabes!
Thanks for your interest and sorry for the lack of examples but for your first question, I think this will work:

mySubscription: {
  subscribe: (_, args) => pubsub.asyncIterator(`project.${args.id}.*`, { pattern: true }),
  resolve: (payload: any, args, context, info) => {
    return payload;
  }
}

If that ends up working, would you consider adding that example to the README?

Regarding your second question, I'm afraid there's no elegant way of doing that without changing the way graphql-js calls the subscriptions resolver. That basically means opening a PR for that.

What is your use case? I wonder if that will be a common enough case to make that change.

[tomasAlabes]

Hi @davidyaha, thanks for your response! Indeed your pattern option worked :) I will create a PR to add it to the readme. Any other option that people should know?

On the 2nd point, in my subscription I send a union of types to the client, so depending on the topic from which I get the message, is the graphql type I'm sending to the client. At the moment I'm sending some metadata in the event itself and from that I create the right gql type. Maybe it's useful to add the topic in the context? Idk. But at least that's my use case.

[davidyaha]

Glad to hear it worked 🎉
A PR with an example would be great!

As far I understand it should be a PR to graphql-js so we should define the use case a bit. Basically what we need is a way to push to the AsyncIterable metadata to be added to something like info variable.

Maybe open a RFC issue on https://github.com/graphql/graphql-js and get some feedback on the idea?

[tomasAlabes]

Created the PR with the example. Thanks for the tip.
I will analyze if the RFC is strong enough and maybe ask there what they think.

Keep up the good work :)

[davidyaha]

Thanks @tomasAlabes!