@nyteshade/lattice-legacy/es6/GQLInterface.js

OO Underpinnings for ease of GraphQL Implementation

/**
 @namespace GQLInterface
 @flow
 */

import { GQLBase } from './GQLBase'
import { GraphQLInterfaceType } from 'graphql'

/**
 * Used by Lattice to implement interface types in the schema when necessary
 *
 * @class GQLInterface
 */
export class GQLInterface extends GQLBase {

  /**
   * This needs to be able to, depending on your implementors, identify
   * which on the data actually is given the model to work with.
   *
   * @memberof GQLInterface
   * @method ⌾⠀resolveType
   * @static
   *
   * @param {mixed} model the data you can use to instantiate the type of
   * object in question.
   * @return {string} a string matching the name of a defined GraphQL type
   * found elsewhere in your schema
   */
  static resolveType(model: mixed): string {
    throw new Error(`
      You must override "resolveType(model)" in your GQLInterface instance
      and determine the implementor type by the contents of the supplied
      model. Returning "null" when nothing matches.
    `);
  }

  /**
   * Denotes that this GQLBase descendent is describing a graphql
   * interface type.
   *
   * @memberof GQLInterface
   * @method ⬇︎⠀GQL_TYPE
   * @static
   * @const
   *
   * @return {Function} a type, such as `GraphQLObjectType` or
   * `GraphQLInterfaceType`
   */
  static get GQL_TYPE(): Function {
    return GraphQLInterfaceType;
  }
}