graphql__egghead_tutorial/src/node.js

'use strict';

const {
  nodeDefinitions,
  fromGlobalId
} = require('graphql-relay');

// At this point, videoType is not yet defined because of the require loop.

const { getObjectById } = require('./data');

const { nodeInterface, nodeField } = nodeDefinitions(
  // Load an object from its id.
  globalId => {
    const { type, id } = fromGlobalId(globalId);
    return getObjectById(type.toLowerCase(), id);
  },
  // Returns the object type.
  object => {
    // But this import is done after the whole loading require loop has completed.
    const { videoType } = require('../index');

    if (object.title) {
      return videoType;
    }

    return null;
  }
);

exports.nodeInterface = nodeInterface;
exports.nodeField = nodeField;