模拟内部 axios.create()

Question

我正在使用 jest 和 axios-mock-adapter 来测试 axios 异步操作创建者中的 axios API 调用。

当我使用使用 axios.create() 创建的 axios 实例时，我无法让它们工作：

import axios from 'axios';

const { REACT_APP_BASE_URL } = process.env;

export const ajax = axios.create({
  baseURL: REACT_APP_BASE_URL,
});

我会在我的async action creator 中使用它，例如：

import { ajax } from '../../api/Ajax'

export function reportGet(data) {
  return async (dispatch, getState) => {
    dispatch({ type: REQUEST_TRANSACTION_DATA })

    try {
      const result = await ajax.post(
         END_POINT_MERCHANT_TRANSACTIONS_GET,
         data,
      )
      dispatch({ type: RECEIVE_TRANSACTION_DATA, data: result.data })
      return result.data
    } catch (e) {
      throw new Error(e);
    }
  }
}

这是我的测试文件：

import {
  reportGet,
  REQUEST_TRANSACTION_DATA,
  RECEIVE_TRANSACTION_DATA,
} from '../redux/TransactionRedux'
import configureMockStore from 'redux-mock-store'
import thunk from 'redux-thunk'
import { END_POINT_MERCHANT_TRANSACTIONS_GET } from 'src/utils/apiHandler'
import axios from 'axios'
import MockAdapter from 'axios-mock-adapter'

const middlewares = [thunk]
const mockStore = configureMockStore(middlewares)
const store = mockStore({ transactions: {} })

test('get report data', async () => {
  let mock = new MockAdapter(axios)

  const mockData = {
    totalSalesAmount: 0
  }

  mock.onPost(END_POINT_MERCHANT_TRANSACTIONS_GET).reply(200, mockData)

  const expectedActions = [
    { type: REQUEST_TRANSACTION_DATA },
    { type: RECEIVE_TRANSACTION_DATA, data: mockData },
  ]

  await store.dispatch(reportGet())
  expect(store.getActions()).toEqual(expectedActions)
})

我只得到一个操作Received: [{"type": "REQUEST_TRANSACTION_DATA"}]，因为ajax.post 出现错误。

我已经尝试了很多方法来模拟 axios.create 无济于事，但我并不真正知道我在做什么。感谢任何帮助。

Answer 1

好的，我明白了。这是我修复它的方法！我最终为axios 做了没有任何模拟库！

在src/__mocks__ 中为axios 创建一个模拟：

// src/__mocks__/axios.ts

const mockAxios = jest.genMockFromModule('axios')

// this is the key to fix the axios.create() undefined error!
mockAxios.create = jest.fn(() => mockAxios)

export default mockAxios

然后在您的测试文件中，要点如下：

import mockAxios from 'axios'
import configureMockStore from 'redux-mock-store'
import thunk from 'redux-thunk'

// for some reason i need this to fix reducer keys undefined errors..
jest.mock('../../store/rootStore.ts')

// you need the 'async'!
test('Retrieve transaction data based on a date range', async () => {
  const middlewares = [thunk]
  const mockStore = configureMockStore(middlewares)
  const store = mockStore()

  const mockData = {
    'data': 123
  }

  /** 
   *  SETUP
   *  This is where you override the 'post' method of your mocked axios and return
   *  mocked data in an appropriate data structure-- {data: YOUR_DATA} -- which
   *  mirrors the actual API call, in this case, the 'reportGet'
   */
  mockAxios.post.mockImplementationOnce(() =>
    Promise.resolve({ data: mockData }),
  )

  const expectedActions = [
    { type: REQUEST_TRANSACTION_DATA },
    { type: RECEIVE_TRANSACTION_DATA, data: mockData },
  ]

  // work
  await store.dispatch(reportGet())

  // assertions / expects
  expect(store.getActions()).toEqual(expectedActions)
  expect(mockAxios.post).toHaveBeenCalledTimes(1)
})

Answer 2

如果您需要创建 Jest 测试，该测试在特定测试中使用 create 模拟 axios（并且不需要所有测试用例的模拟 axios，如其他答案中所述) 你也可以使用：

const axios = require("axios");

jest.mock("axios");

beforeAll(() => {
    axios.create.mockReturnThis();
});

test('should fetch users', () => {
    const users = [{name: 'Bob'}];
    const resp = {data: users};
    axios.get.mockResolvedValue(resp);

    // or you could use the following depending on your use case:
    // axios.get.mockImplementation(() => Promise.resolve(resp))

    return Users.all().then(data => expect(data).toEqual(users));
});

这里是没有create 的Axios mocking in Jest 的相同示例的链接。不同的是要加axios.create.mockReturnThis()

Answer 3

在您的 mockAdapter 中，您模拟了错误的实例。您应该改为模拟 ajax。像这样，const mock = MockAdapter(ajax) 这是因为您现在不是在模拟 axios 实例，而是在模拟 ajax，因为它是您用来发送请求的那个，也就是说，您在执行 export const ajax = axios.create...so 时创建了一个名为 ajax 的 axios 实例，因为您'在你的代码中做const result = await ajax.post，它应该被模拟的axios的ajax实例，而不是axios在这种情况下。

Answer 4

我有另一个解决方案。

import {
  reportGet,
  REQUEST_TRANSACTION_DATA,
  RECEIVE_TRANSACTION_DATA,
} from '../redux/TransactionRedux'
import configureMockStore from 'redux-mock-store'
import thunk from 'redux-thunk'
import { END_POINT_MERCHANT_TRANSACTIONS_GET } from 'src/utils/apiHandler'
// import axios from 'axios'
import { ajax } from '../../api/Ajax' // axios instance
import MockAdapter from 'axios-mock-adapter'

const middlewares = [thunk]
const mockStore = configureMockStore(middlewares)
const store = mockStore({ transactions: {} })

test('get report data', async () => {
  // let mock = new MockAdapter(axios)
  let mock = new MockAdapter(ajax) // this here need to mock axios instance

  const mockData = {
    totalSalesAmount: 0
  }

  mock.onPost(END_POINT_MERCHANT_TRANSACTIONS_GET).reply(200, mockData)

  const expectedActions = [
    { type: REQUEST_TRANSACTION_DATA },
    { type: RECEIVE_TRANSACTION_DATA, data: mockData },
  ]

  await store.dispatch(reportGet())
  expect(store.getActions()).toEqual(expectedActions)
})

Answer 5

这是我对 axios 的模拟

export default {
    defaults:{
        headers:{
            common:{
                "Content-Type":"",
                "Authorization":""
            }
        }
  },
  get: jest.fn(() => Promise.resolve({ data: {} })),
  post: jest.fn(() => Promise.resolve({ data: {} })),
  put: jest.fn(() => Promise.resolve({ data: {} })),
  delete: jest.fn(() => Promise.resolve({ data: {} })),
  create: jest.fn(function () {
      return {
          interceptors:{
              request : {  
                  use: jest.fn(() => Promise.resolve({ data: {} })),
              }
          },

          defaults:{
                headers:{
                    common:{
                        "Content-Type":"",
                        "Authorization":""
                    }
                }
          },
          get: jest.fn(() => Promise.resolve({ data: {} })),
          post: jest.fn(() => Promise.resolve({ data: {} })),
          put: jest.fn(() => Promise.resolve({ data: {} })),
          delete: jest.fn(() => Promise.resolve({ data: {} })),
      }
  }),
};

Answer 6

以下代码有效！

   jest.mock("axios", () => {
        return {
            create: jest.fn(() => axios),
            post: jest.fn(() => Promise.resolve()),
        };
    });