Add Promise Support to @graphql-tools/resolvers-composition

[zwymer]

I am trying to gate our GraphQL Mesh endpoint behind Launch Darkly feature flags. I am trying to use @graphql-tools/resolvers-composition to do so. Their NodeJS client is event-based which means I need to leverage promises / async functions in the resolversComposition function. A rough example looks like:

In my .mesh.yml

transforms:
  - resolversComposition:
      compositions:
        - resolver: 'Query.*'
          composer: can-access-feature#canAccessFeature
        - resolver: 'Mutation.*'
          composer: can-access-feature#canAccessFeature

In my can-access-feature.js

const ld = require('launchdarkly-node-server-sdk')
let ldClient;

const initLDClient = () => new Promise((resolve, reject) => {
    if (ldClient === undefined) {
        console.log('initializing ld client')
        ldClient = ld.init("sdk-XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXX");
        ldClient.once('ready', () => {
            console.log('ld client ready')
            return resolve(ldClient)
        })
    }
    return ldClient;
})

module.exports = {
    canAccessFeature: next => async (root, args, context, info) => {
        const ldContext = {
            "kind": 'user',
            "key": 'user-key-123abc',
            "name": 'Sandy'
        };

        ldClient = await initLDClient();

        const canAccessFlag = await ldClient.variation('flag-key-123abc', ldContext, true);
        if (canAccessFlag) {
            console.log('We can access our flag!')
            return next(root, args, context, info)            
        } else {
            console.log('No dice :(')
        }
    }
}

Is this a feature you all would consider?

Warm Regards,
Zach