Subscriptions not working with Prisma 2 and Nexus?

Question

Subscriptions with Nexus are undocumented but I searched Github and tried every example in the book. It's just not working for me.

I have cloned Prisma2 GraphQL boilerplate project & my files are as follows:

prisma/schema.prisma

datasource db {
  provider = "sqlite"
  url      = "file:dev.db"
  default  = true
}

generator photon {
  provider = "photonjs"
}

generator nexus_prisma {
  provider = "nexus-prisma"
}

model Pokemon {
  id      String         @default(cuid()) @id @unique
  number  Int            @unique
  name    String
  attacks PokemonAttack?
}

model PokemonAttack {
  id      Int      @id
  special Attack[]
}

model Attack {
  id     Int    @id
  name   String
  damage String
}

src/index.js

const { GraphQLServer } = require('graphql-yoga')
const { join } = require('path')
const { makeSchema, objectType, idArg, stringArg, subscriptionField } = require('@prisma/nexus')
const Photon = require('@generated/photon')
const { nexusPrismaPlugin } = require('@generated/nexus-prisma')

const photon = new Photon()

const nexusPrisma = nexusPrismaPlugin({
  photon: ctx => ctx.photon,
})

const Attack = objectType({
  name: "Attack",
  definition(t) {
    t.model.id()
    t.model.name()
    t.model.damage()
  }
})

const PokemonAttack = objectType({
  name: "PokemonAttack",
  definition(t) {
    t.model.id()
    t.model.special()
  }
})

const Pokemon = objectType({
  name: "Pokemon",
  definition(t) {
    t.model.id()
    t.model.number()
    t.model.name()
    t.model.attacks()
  }
})

const Query = objectType({
  name: 'Query',
  definition(t) {
    t.crud.findManyPokemon({
      alias: 'pokemons'
    })
    t.list.field('pokemon', {
      type: 'Pokemon',
      args: {
        name: stringArg(),
      },
      resolve: (parent, { name }, ctx) => {
        return ctx.photon.pokemon.findMany({
          where: {
              name
          }
        })
      },
    })
  },
})

const Mutation = objectType({
  name: 'Mutation',
  definition(t) {
    t.crud.createOnePokemon({ alias: 'addPokemon' })
  },
})

const Subscription = subscriptionField('newPokemon', {
  type: 'Pokemon',
  subscribe: (parent, args, ctx) => {
    return ctx.photon.$subscribe.pokemon()
  },
  resolve: payload => payload
})

const schema = makeSchema({
  types: [Query, Mutation, Subscription, Pokemon, Attack, PokemonAttack, nexusPrisma],
  outputs: {
    schema: join(__dirname, '/schema.graphql')
  },
  typegenAutoConfig: {
    sources: [
      {
        source: '@generated/photon',
        alias: 'photon',
      },
    ],
  },
})

const server = new GraphQLServer({
  schema,
  context: request => {
    return {
      ...request,
      photon,
    }
  },
})

server.start(() => console.log(`🚀 Server ready at http://localhost:4000`))

The related part is the Subscription which I don't know why it's not working or how it's supposed to work.

I searched Github for this query which results in all projects using Subscriptions .

I also found out this commit in this project to be relevant to my answer. Posting the related code here for brevity:

import { subscriptionField } from 'nexus';
import { idArg } from 'nexus/dist/core';
import { Context } from './types';

 export const PollResultSubscription = subscriptionField('pollResult', {
  type: 'AnswerSubscriptionPayload',
  args: {
    pollId: idArg(),
  },
  subscribe(_: any, { pollId }: { pollId: string }, context: Context) {
    // Subscribe to changes on answers in the given poll
    return context.prisma.$subscribe.answer({
      node: { poll: { id: pollId } },
    });
  },
  resolve(payload: any) {
    return payload;
  },
});

Which is similar to what I do. But they do have AnswerSubscriptionPayload & I don't get any generated type that contains Subscription in it.

How do I solve this? I think I am doing everything right but it's still not working. Every example on GitHub is similar to above & even I am doing the same thing.

Any suggestions?

Edit: Subscriptions aren't implemented yet :(

Answer 1

I seem to have got this working despite subscriptions not being implemented. I have a working pubsub proof of concept based off the prisma2 boilerplate and Ben Awad's video tutorial https://youtu.be/146AypcFvAU . Should be able to get this up and running with redis and websockets to handle subscriptions until the prisma2 version is ready.

https://github.com/ryanking1809/prisma2_subscriptions

Answer 2

Subscriptions aren't implemented yet.

I've opened up an issue to track it.

I'll edit this answer as soon as it's implemented in Prisma 2.