Decorate existing network interface?

[thebigredgeek]

Very pleased with this package. Glad I won't need to roll my own solution haha. I was wondering if we could expose a higher-order function to decorate an existing network interface? I am currently doing the following for subscriptions:

import { print } from 'graphql-tag/printer';

// quick way to add the subscribe and unsubscribe functions to the network interface
export default function addGraphQLSubscriptions(networkInterface, wsClient) {
  return Object.assign(networkInterface, {
    subscribe(request, handler) {
      return wsClient.subscribe({
        query: print(request.query),
        variables: request.variables,
      }, handler);
    },
    unsubscribe(id) {
      wsClient.unsubscribe(id);
    },
  });
}

It seems like this will be a normal pattern moving forward for extended the default apollo network interface. I don't think it would be too difficult to expose an interface for something like this, and I am willing to submit a PR if you don't have time for it.

Thoughts @HriBB ?

[HriBB]

@thebigredgeek yeah I am busy these days, so go for it!

I am already extending HTTPFetchNetworkInterface (here), so it should be easy to create a HOC to decorate existing interface. My initial implementation included a middleware for the NetworkInterface, but the problem is this line, because it's not possible to override 'Content-Type` easily. One more thing we need to consider is batching. Also I want to wait till the API is finalized.

[jaydenseric]

To get batching to work, you need to use createBatchingNetworkInterface.

I can't work out how to get both custom interfaces to work together:

import ApolloClient, {createBatchingNetworkInterface} from 'apollo-client'
import createNetworkInterface from 'apollo-upload-network-interface'

Does this mean there is no way to get this project to work with batching?

[HriBB]

@jaydenseric there is now way to make this project work with batching ATM. Personally I don't need it, but you are welcome to make a PR ;) Hopefully the apollo team will add official support for file uploads. If not, we can implement batching once the API is finalized and the client hits v1.0.