Schema configuration example for commit "Create schema2.js for getting more granular schema configuration" (https://github.com/nodkz/graffiti-mongoose/commit/08aa4a394c8b53a442ec05929f1b0035418a1ae0).

app_schema.js

// This gist is a draft solution for extending graphQL schemas generated by graffiti.

import { getSchema, addMongooseModel, getGQType, getExistedType } from 'lib/graffiti-mongoose/src/schema/schema2';
import { User } from 'app/_schema/mongoose/user';
import { Cv } from 'app/_schema/mongoose/cv';
import { UserData } from 'app/_schema/mongoose/userData';

import ExtraFieldsWrapper from 'lib/graffiti-mongoose/src/wrappers/extra-fields';
import getFieldList from 'lib/graffiti-mongoose/src/query/projection';

addMongooseModel(User);

// add mongoose model `UserData` to graffiti-models cache. 
// Second param `false` said that this model should not be resolved in the root queries.
addMongooseModel(UserData, false);

let CvWrapped = Cv;

// This is graffiti wrapper for mongoose model, which add one more field `userData` to `Cv` type in graphql.
CvWrapped = new ExtraFieldsWrapper(CvWrapped, {
  extraFields: {
    userData: {
      type: getGQType(UserData), // this is gq type generator from mongoose model, which was added to graffiti model cache
      description: 'Current user data for this object',
      resolve(obj, args, ast) {
        const userId = '56fa846b47c6c2be5bee528a';
        return UserDataByRef.findByUser(userId).select(getFieldList(ast)).limit(1).then(
          (result) => {
            if (result && result[0]) {
              return {
                ...result[0].toObject(),
                _type: UserDataByRef.modelName,
              };
            }

            return null;
          }
        );
      },
    },
  },
});

const UserDataInterface = new GraphQLInterfaceType({
  name: 'UserDatable',
  description: 'An object with user data (fav, notes, etc)',
  fields: () => ({
    userData: {
      type: getGQType(UserData),
      description: 'Current user data (fav, notes) for this object',
    },
  }),
  resolveType: (obj) => (obj._type ? getExistedType(obj._type) : null),
});

// wrapper for adding interfaces
CvWrapped = new ExtraInterfacesWrapper(CvWrapped, { extraInterfaces: [UserDataInterface] });

// after wrapping mongoose model `Cv` we add it to graffiti models
addMongooseModel(CvWrapped);

// getSchema accept only options, because internally use models which was added via `addMongooseModel(MongooseModel, true);`
const Schema = getSchema();
export default Schema;