Codegen from Apollo executableSchema object

[piglovesyou]

This is a feature proposal which would be the third option of service to achieve codegen.

Problem

I need to launch a GraphQL server on CI even though I don't need it.

• I don't want to include any auto-generated files including introspection schema files in Git
• I'd like to pass static type checking on CI with type files in __generated__.
• So I need to do Codegen on CI
• To do that, currently I need to do the following steps in yarn codegen:
  1. Start GraphQL server with my executableSchema object
  2. Run apollo client:codegen command
  3. Stop the server

Launching a server is redundant, since we have apollo-link-schema which make it possible to communicate with GraphQL without HTTP servers.

Solution

Why don't we accept the third option for service in apollo.config.js like this:

const { makeExecutableSchema } = require('graphql-tools');
const { default as schema } = require('./src/data/schema');

module.exports = {
  service: {
    executableSchema: {
      schema: makeExecutableSchema(schema),
      context: {},
    },
  },
};

which is passed as a parameter to SchemaLink of apollo-link-schema.

I know Apollo Tooling avoids implementing Apollo Server-specific features, but I think it's efficient for Apollo toolset users.