next-deploy/packages/aws-lambda-builder/__tests__/default-handler/default-handler.test.ts

import { handler } from '../../src/default-handler';
import { createCloudFrontEvent } from '../test-utils';
import {
  CloudFrontRequest,
  CloudFrontResultResponse,
  CloudFrontHeaders,
  CloudFrontOrigin,
} from 'aws-lambda';

jest.mock('../../src/manifest.json', () => require('./default-build-manifest.json'), {
  virtual: true,
});

jest.mock('../../src/prerender-manifest.json', () => require('./prerender-manifest.json'), {
  virtual: true,
});

const mockPageRequire = (mockPagePath: string): void => {
  jest.mock(
    `../../src/${mockPagePath}`,
    () => require(`../shared-fixtures/built-artifact/${mockPagePath}`),
    {
      virtual: true,
    }
  );
};

describe('Lambda@Edge', () => {
  describe('Routing', () => {
    describe('HTML pages routing', () => {
      it.each`
        path                                               | expectedPage
        ${'/'}                                             | ${'/index.html'}
        ${'/index'}                                        | ${'/index.html'}
        ${'/terms'}                                        | ${'/terms.html'}
        ${'/users/batman'}                                 | ${'/users/[user].html'}
        ${'/users/test/catch/all'}                         | ${'/users/[...user].html'}
        ${'/john/123'}                                     | ${'/[username]/[id].html'}
        ${'/tests/prerender-manifest/example-static-page'} | ${'/tests/prerender-manifest/example-static-page.html'}
      `('serves page $expectedPage from S3 for path $path', async ({ path, expectedPage }) => {
        const event = createCloudFrontEvent({
          uri: path,
          host: 'mydistribution.cloudfront.net',
        });

        const result = await handler(event);

        const request = result as CloudFrontRequest;

        expect(request.origin).toEqual({
          s3: {
            authMethod: 'origin-access-identity',
            domainName: 'my-bucket.s3.amazonaws.com',
            path: '/static-pages',
            region: 'us-east-1',
          },
        });
        expect(request.uri).toEqual(expectedPage);
        expect(request.headers.host[0].key).toEqual('host');
        expect(request.headers.host[0].value).toEqual('my-bucket.s3.amazonaws.com');
      });
    });

    describe('Public files routing', () => {
      it('serves public file from S3 /public folder', async () => {
        const event = createCloudFrontEvent({
          uri: '/manifest.json',
          host: 'mydistribution.cloudfront.net',
        });

        const result = await handler(event);

        const request = result as CloudFrontRequest;

        expect(request.origin).toEqual({
          s3: {
            authMethod: 'origin-access-identity',
            domainName: 'my-bucket.s3.amazonaws.com',
            path: '/public',
            region: 'us-east-1',
          },
        });
        expect(request.uri).toEqual('/manifest.json');
      });
    });

    describe('SSR pages routing', () => {
      it.each`
        path                              | expectedPage
        ${'/abc'}                         | ${'pages/[root].js'}
        ${'/blog/foo'}                    | ${'pages/blog/[id].js'}
        ${'/customers'}                   | ${'pages/customers/index.js'}
        ${'/customers/superman'}          | ${'pages/customers/[customer].js'}
        ${'/customers/superman/howtofly'} | ${'pages/customers/[customer]/[post].js'}
        ${'/customers/superman/profile'}  | ${'pages/customers/[customer]/profile.js'}
        ${'/customers/test/catch/all'}    | ${'pages/customers/[...catchAll].js'}
      `('renders page $expectedPage for path $path', async ({ path, expectedPage }) => {
        const event = createCloudFrontEvent({
          uri: path,
          host: 'mydistribution.cloudfront.net',
        });

        mockPageRequire(expectedPage);

        const response = await handler(event);

        const cfResponse = response as CloudFrontResultResponse;
        const decodedBody = new Buffer(cfResponse.body as string, 'base64').toString('utf8');

        expect(decodedBody).toEqual(expectedPage);
        expect(cfResponse.status).toEqual(200);
      });
    });

    describe('Data Requests', () => {
      it.each`
        path                                                      | expectedPage
        ${'/_next/data/build-id/customers.json'}                  | ${'pages/customers/index.js'}
        ${'/_next/data/build-id/customers/superman.json'}         | ${'pages/customers/[customer].js'}
        ${'/_next/data/build-id/customers/superman/profile.json'} | ${'pages/customers/[customer]/profile.js'}
      `('serves json data for path $path', async ({ path, expectedPage }) => {
        const event = createCloudFrontEvent({
          uri: path,
          host: 'mydistribution.cloudfront.net',
        });

        mockPageRequire(expectedPage);

        const result = await handler(event);

        const response = result as CloudFrontResultResponse;
        const decodedBody = new Buffer(response.body as string, 'base64').toString('utf8');

        const headers = response.headers as CloudFrontHeaders;
        expect(headers['content-type'][0].value).toEqual('application/json');
        expect(JSON.parse(decodedBody)).toEqual({
          page: expectedPage,
        });
        expect(response.status).toEqual(200);
      });
    });

    it('uses default s3 endpoint when bucket region is us-east-1', async () => {
      const event = createCloudFrontEvent({
        uri: '/terms',
        host: 'mydistribution.cloudfront.net',
        s3Region: 'us-east-1',
      });

      const result = await handler(event);

      const request = result as CloudFrontRequest;
      const origin = request.origin as CloudFrontOrigin;

      expect(origin.s3).toEqual(
        expect.objectContaining({
          domainName: 'my-bucket.s3.amazonaws.com',
        })
      );
      expect(request.headers.host[0].key).toEqual('host');
      expect(request.headers.host[0].value).toEqual('my-bucket.s3.amazonaws.com');
    });

    it('uses regional endpoint when bucket region is not us-east-1', async () => {
      const event = createCloudFrontEvent({
        uri: '/terms',
        host: 'mydistribution.cloudfront.net',
        s3DomainName: 'my-bucket.s3.amazonaws.com',
        s3Region: 'eu-west-1',
      });

      const result = await handler(event);

      const request = result as CloudFrontRequest;
      const origin = request.origin as CloudFrontOrigin;

      expect(origin).toEqual({
        s3: {
          authMethod: 'origin-access-identity',
          domainName: 'my-bucket.s3.eu-west-1.amazonaws.com',
          path: '/static-pages',
          region: 'eu-west-1',
        },
      });
      expect(request.uri).toEqual('/terms.html');
      expect(request.headers.host[0].key).toEqual('host');
      expect(request.headers.host[0].value).toEqual('my-bucket.s3.eu-west-1.amazonaws.com');
    });
  });

  it("renders 404 page if request path can't be matched to any page / api routes", async () => {
    const event = createCloudFrontEvent({
      uri: '/page/does/not/exist',
      host: 'mydistribution.cloudfront.net',
    });

    mockPageRequire('pages/_error.js');

    const response = (await handler(event)) as CloudFrontResultResponse;
    const body = response.body as string;
    const decodedBody = new Buffer(body, 'base64').toString('utf8');

    expect(decodedBody).toEqual('pages/_error.js');
    expect(response.status).toEqual(200);
  });
});