如何使用jest模拟Auth0 MangementClient？

Question

这也是Auth0 node-auth0 library上的一个问题。用例是，我通过Terraform使用Auth0 create Actions API，并希望能够针对这些操作编写测试。

在本例中，我希望能够在不使用实际值的情况下测试onExecutePostLogin。

// auth0-post-login.js

exports.onExecutePostLogin = async (event, api) => {
  const userId = event.user.user_id

  const ManagementClient = require('auth0').ManagementClient
  const management = new ManagementClient({
    domain: event.secrets.domain,
    clientId: event.secrets.clientId,
    clientSecret: event.secrets.clientSecret,
    audience: `https://${event.secrets.domain}/api/v2/`,
    scope: 'read:users',
  })

  const params = { id: userId, page: 0, per_page: 50, include_totals: false }
  let userPermissions = await management.getUserPermissions(params)
  const map = require('array-map')
  const permissions = map(userPermissions, function(permission) {
    return permission.permission_name
  })

  api.accessToken.setCustomClaim('https://example.com/access', permissions.join(' '))
}

其中一个主要问题是，像getUserPermissions这样的函数是通过它们的实用程序包装器创建的：

utils.wrapPropertyMethod(ManagementClient, 'getUserPermissions', 'users.getPermissions');

这会导致jest在查找函数时出现问题。

Answer 1

为了实现像getUserPermissions这样的函数，我需要覆盖ManagementClient的实现。这使我能够将getUserPermissions定义为模拟函数。

import { onExecutePostLogin } from './auth0-post-login'

const mockManagementClient = jest.fn()
const mockGetUserPermissions = jest.fn()

jest.mock('auth0', () => {
  return {
    ManagementClient: (opts) => {
      mockManagementClient(opts)
      return {
        getUserPermissions: (params) => {
          return mockGetUserPermissions(params)
        },
      }
    },
  }
})

describe('onExecutePostLogin', () => {
  const mockSetCustomClaim = jest.fn()

  beforeEach(() => {
    mockSetCustomClaim.mockClear()
    mockManagementClient.mockClear()
    mockGetUserPermissions.mockClear()
    mockGetUserPermissions.mockReturnValue([
      {
        permission_name: 'read:foo',
      },
      {
        permission_name: 'update:bar',
      },
    ])
  })

  const event = {
    user: {
      user_id: 'abcd123',
    },
    secrets: {
      domain: 'test-example.us.auth0.com',
      clientId: 'a-client-id',
      clientSecret: 'a-client-secret',
    },
  }

  const api = {
    accessToken: {
      setCustomClaim: mockSetCustomClaim,
    },
  }

  it('initializes a ManagementClient', async () => {
    await onExecutePostLogin(event, api)

    expect(mockManagementClient).toHaveBeenCalledWith({
      domain: event.secrets.domain,
      clientId: event.secrets.clientId,
      clientSecret: event.secrets.clientSecret,
      audience: `https://${event.secrets.domain}/api/v2/`,
      scope: 'read:users',
    })
  })

  it('gets users permissions', async () => {
    await onExecutePostLogin(event, api)

    expect(mockGetUserPermissions).toHaveBeenCalledWith(
      { id: event.user.user_id, page: 0, per_page: 50, include_totals: false },
    )
  })

  it('sets custom claims', async () => {
    await onExecutePostLogin(event, api)

    const expectedPermissions = 'read:foo update:bar'
    expect(mockSetCustomClaim).toHaveBeenCalledWith(
      'https://example.com/access', expectedPermissions,
    )
  })
})

Answer 2

我做了一些类似于stsmurf的事情来模拟Auth0方法的响应。

我有一个文件，其中存储了我的帮助器方法，比如“按名称查找角色”

// helper.ts

import { ManagementClient } from 'auth0';

export const getRoleByName = async (roleName: string) => {
  const api = new ManagementClient({
    clientId: clientId,
    clientSecret: clientSecret,
    domain: domain,
  });

  const roles = await api.getRoles();
  const role = roles.find((r) => r.name == roleName);
  if (!role) throw new Error('Role not found');

  return role;
};

// helper.test.ts

import { Role } from 'auth0';

import { getRoleByName } from './helpers';

const mockGetRoles = jest.fn();
jest.mock('auth0', () => {
  return {
    ManagementClient: jest.fn().mockImplementation(() => {
      return {
        getRoles: mockGetRoles,
      };
    }),
  };
});

describe('Get role', () => {
  beforeAll(() => {
    const dummyRoles: Role[] = [
      { id: 'fake_id_1', description: 'Fake role nr 1', name: 'Fake Role 1' },
      { id: 'fake_id_2', description: 'Fake role nr 2', name: 'Fake Role 2' },
    ];
    mockGetRoles.mockImplementation(() => dummyRoles);
  });

  it('can return a role if it exists', async () => {
    const expectedResult: Role = {
      id: 'fake_id_1',
      description: 'Fake role nr 1',
      name: 'Fake Role 1',
    };
    const result = await getRoleByName('Fake Role 1');

    expect(expectedResult).toEqual(result);
  });

  it('will throw an error when a role is not found', async () => {
    await expect(getRoleByName('Fake Role 3')).rejects.toThrowError();
  });
});