testAlternateMergeSchemas.ts

/* tslint:disable:no-unused-expression */

import { expect } from 'chai';
import {
  graphql,
  GraphQLSchema,
  ExecutionResult,
  subscribe,
  parse,
} from 'graphql';
import mergeSchemas from '../stitching/mergeSchemas';
import {
  transformSchema,
  FilterRootFields,
  RenameTypes,
  RenameRootFields,
} from '../transforms';
import {
  propertySchema,
  bookingSchema,
  subscriptionSchema,
  subscriptionPubSub,
  subscriptionPubSubTrigger,
} from './testingSchemas';
import { forAwaitEach } from 'iterall';

let linkSchema = `
  """
  A new type linking the Property type.
  """
  type LinkType {
    test: String
    """
    The property.
    """
    property: Properties_Property
  }

  interface Node {
    id: ID!
  }

  extend type Bookings_Booking implements Node {
    """
    The property of the booking.
    """
    property: Properties_Property
  }

  extend type Properties_Property implements Node {
    """
    A list of bookings.
    """
    bookings(
      """
      The maximum number of bookings to retrieve.
      """
      limit: Int
    ): [Bookings_Booking]
  }

  extend type Query {
    linkTest: LinkType
    node(id: ID!): Node
    nodes: [Node]
  }

  extend type Bookings_Customer implements Node
`;

describe('merge schemas through transforms', () => {
  let mergedSchema: GraphQLSchema;

  before(async () => {
    // namespace and strip schemas
    const transformedPropertySchema = transformSchema(propertySchema, [
      new FilterRootFields(
        (operation: string, rootField: string) =>
          'Query.properties' === `${operation}.${rootField}`,
      ),
      new RenameTypes((name: string) => `Properties_${name}`),
      new RenameRootFields((name: string) => `Properties_${name}`),
    ]);
    const transformedBookingSchema = transformSchema(bookingSchema, [
      new FilterRootFields(
        (operation: string, rootField: string) =>
          'Query.bookings' === `${operation}.${rootField}`,
      ),
      new RenameTypes((name: string) => `Bookings_${name}`),
      new RenameRootFields(
        (operation: string, name: string) => `Bookings_${name}`,
      ),
    ]);
    const transformedSubscriptionSchema = transformSchema(subscriptionSchema, [
      new FilterRootFields(
        (operation: string, rootField: string) =>
          // must include a Query type otherwise graphql will error
          'Query.notifications' === `${operation}.${rootField}` ||
          'Subscription.notifications' === `${operation}.${rootField}`,
      ),
      new RenameTypes((name: string) => `Subscriptions_${name}`),
      new RenameRootFields(
        (operation: string, name: string) => `Subscriptions_${name}`),
    ]);

    mergedSchema = mergeSchemas({
      schemas: [
        transformedPropertySchema,
        transformedBookingSchema,
        transformedSubscriptionSchema,
        linkSchema,
      ],
      resolvers: {
        Query: {
          // delegating directly, no subschemas or mergeInfo
          node(parent, args, context, info) {
            if (args.id.startsWith('p')) {
              return info.mergeInfo.delegateToSchema({
                schema: propertySchema,
                operation: 'query',
                fieldName: 'propertyById',
                args,
                context,
                info,
                transforms: transformedPropertySchema.transforms,
              });
            } else if (args.id.startsWith('b')) {
              return info.mergeInfo.delegateToSchema({
                schema: bookingSchema,
                operation: 'query',
                fieldName: 'bookingById',
                args,
                context,
                info,
                transforms: transformedBookingSchema.transforms,
              });
            } else if (args.id.startsWith('c')) {
              return info.mergeInfo.delegateToSchema({
                schema: bookingSchema,
                operation: 'query',
                fieldName: 'customerById',
                args,
                context,
                info,
                transforms: transformedBookingSchema.transforms,
              });
            } else {
              throw new Error('invalid id');
            }
          },
        },
        Properties_Property: {
          bookings: {
            fragment: 'fragment PropertyFragment on Property { id }',
            resolve(parent, args, context, info) {
              return info.mergeInfo.delegateToSchema({
                schema: bookingSchema,
                operation: 'query',
                fieldName: 'bookingsByPropertyId',
                args: {
                  propertyId: parent.id,
                  limit: args.limit ? args.limit : null,
                },
                context,
                info,
                transforms: transformedBookingSchema.transforms,
              });
            },
          },
        },
        Bookings_Booking: {
          property: {
            fragment: 'fragment BookingFragment on Booking { propertyId }',
            resolve(parent, args, context, info) {
              return info.mergeInfo.delegateToSchema({
                schema: propertySchema,
                operation: 'query',
                fieldName: 'propertyById',
                args: {
                  id: parent.propertyId,
                },
                context,
                info,
                transforms: transformedPropertySchema.transforms,
              });
            },
          },
        },
      },
    });
  });

  // FIXME fragemnt replacements
  it('node should work', async () => {
    const result = await graphql(
      mergedSchema,
      `
        query($pid: ID!, $bid: ID!) {
          property: node(id: $pid) {
            __typename
            ... on Properties_Property {
              name
              bookings {
                startTime
                endTime
              }
            }
          }
          booking: node(id: $bid) {
            __typename
            ... on Bookings_Booking {
              startTime
              endTime
              property {
                id
                name
              }
            }
          }
        }
      `,
      {},
      {},
      {
        pid: 'p1',
        bid: 'b1',
      },
    );

    expect(result).to.deep.equal({
      data: {
        booking: {
          __typename: 'Bookings_Booking',
          endTime: '2016-06-03',
          property: {
            id: 'p1',
            name: 'Super great hotel',
          },
          startTime: '2016-05-04',
        },
        property: {
          __typename: 'Properties_Property',
          bookings: [
            {
              endTime: '2016-06-03',
              startTime: '2016-05-04',
            },
            {
              endTime: '2016-07-03',
              startTime: '2016-06-04',
            },
            {
              endTime: '2016-09-03',
              startTime: '2016-08-04',
            },
          ],
          name: 'Super great hotel',
        },
      },
    });
  });

  it('local subscriptions should work even if root fields are renamed', done => {
    const originalNotification = {
      notifications: {
        text: 'Hello world',
      },
    };

    const transformedNotification = {
      Subscriptions_notifications: originalNotification.notifications
    };

    const subscription = parse(`
      subscription Subscription {
        Subscriptions_notifications {
          text
        }
      }
    `);

    let notificationCnt = 0;
    subscribe(mergedSchema, subscription)
      .then(results => {
        forAwaitEach(
          results as AsyncIterable<ExecutionResult>,
          (result: ExecutionResult) => {
            expect(result).to.have.property('data');
            expect(result.data).to.deep.equal(transformedNotification);
            !notificationCnt++ ? done() : null;
          },
        ).catch(done);
      }).then(() => {
        subscriptionPubSub.publish(subscriptionPubSubTrigger, originalNotification);
      }).catch(done);
  });
});

describe('interface resolver inheritance', () => {
  const testSchemaWithInterfaceResolvers = `
    interface Node {
      id: ID!
    }
    type User implements Node {
      id: ID!
      name: String!
    }
    type Query {
      user: User!
    }
    schema {
      query: Query
    }
  `;
  const user = { _id: 1, name: 'Ada', type: 'User' };
  const resolvers = {
    Node: {
      __resolveType: ({ type }: { type: string }) => type,
      id: ({ _id }: { _id: number }) => `Node:${_id}`,
    },
    User: {
      name: ({ name }: { name: string}) => `User:${name}`
    },
    Query: {
      user: () => user
    }
  };

  it('copies resolvers from interface', async () => {
    const mergedSchema = mergeSchemas({
      schemas: [
        // pull in an executable schema just so mergeSchema doesn't complain
        // about not finding default types (e.g. ID)
        propertySchema,
        testSchemaWithInterfaceResolvers
      ],
      resolvers,
      inheritResolversFromInterfaces: true
    });
    const query = `{ user { id name } }`;
    const response = await graphql(mergedSchema, query);
    expect(response).to.deep.equal({
      data: {
        user: {
          id: `Node:1`,
          name: `User:Ada`
        }
      }
    });
  });

  it('does not copy resolvers from interface when flag is false',
async () => {
    const mergedSchema = mergeSchemas({
      schemas: [
        // pull in an executable schema just so mergeSchema doesn't complain
        // about not finding default types (e.g. ID)
        propertySchema,
        testSchemaWithInterfaceResolvers
      ],
      resolvers,
      inheritResolversFromInterfaces: false
    });
    const query = `{ user { id name } }`;
    const response = await graphql(mergedSchema, query);
    expect(response.errors.length).to.equal(1);
    expect(response.errors[0].message).to.equal('Cannot return null for ' +
      'non-nullable field User.id.');
    expect(response.errors[0].path).to.deep.equal(['user', 'id']);
  });

  it('does not copy resolvers from interface when flag is not provided',
async () => {
    const mergedSchema = mergeSchemas({
      schemas: [
        // pull in an executable schema just so mergeSchema doesn't complain
        // about not finding default types (e.g. ID)
        propertySchema,
        testSchemaWithInterfaceResolvers
      ],
      resolvers
    });
    const query = `{ user { id name } }`;
    const response = await graphql(mergedSchema, query);
    expect(response.errors.length).to.equal(1);
    expect(response.errors[0].message).to.equal('Cannot return null for ' +
      'non-nullable field User.id.');
    expect(response.errors[0].path).to.deep.equal(['user', 'id']);
  });
});