subscriptions_apollo.js

# Comment on a repository, returns the new comment
submitComment(
  # The full repository name from GitHub, e.g. "apollostack/GitHunt-API"
  repoFullName: String!,
  # The text content for the new comment
  commentContent: String!
): Comment

type Subscription {
  # Subscription fires on every comment added
  commentAdded(repoFullName: String!): Comment
}

// later in the file

submitComment(root, { repoFullName, commentContent }, context) {
  return Promise.resolve()
    .then(() => (
      # create comment
      )
    ))
    .then((comment) => {
      // publish subscription notification
      pubsub.publish('commentAdded', comment);
      return comment;
    });
},

// and then in a totally separate file

import { PubSub, SubscriptionManager } from 'graphql-subscriptions';
import schema from './schema';

const pubsub = new PubSub();
const subscriptionManager = new SubscriptionManager({
  schema,
  pubsub,
  setupFunctions: {
    commentAdded: (options, args) => ({
      commentAdded: comment => comment.repository_name === args.repoFullName,
    }),
  },
});

export { subscriptionManager, pubsub };