Nest.js + Apollo GraphQL Federation + subscription

[adamatti]

Is there an existing issue that is already proposing this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe it

Not exactly a problem, but today graphql subscription is not supported using federation.

There is a explicit throw in the code about it here

    // class ApolloFederationDriver
    if (options.installSubscriptionHandlers || options.subscriptions) {
      // TL;DR <https://github.com/apollographql/apollo-server/issues/2776>
      throw new Error(
        'No support for subscriptions yet when using Apollo Federation',
      );
    }

Describe the solution you'd like

Graphql clients will be able to use subscription calling the federated service/gateway

Teachability, documentation, adoption, migration strategy

Not 100% sure how it would be implemented.
IMHO, no migration is needed

What is the motivation / use case for changing the behavior?

We have a microservices infrastructure and would like to have different services exposing subscriptions, so the client (ui / front) would be able to subscribe only knowing the federation gateway endpoint

[kamilmysliwiec]

Duplicate nestjs/graphql#2879