用于API的NodeJS中的Stub DynamoDB

我有一个问题是存根调用DynamoDB进行API测试。我正在使用无服务器的mocha，并希望从端到端的角度测试我的API。项目结构并不简单，但在API文件本身内部，我对不同的类文件进行单独调用以实际使用DynamoDB函数。我们假设它是一个库。所以，我不能使用aws-sdk-mock，因为要求“AWS服务需要在被测试的函数内初始化以便模拟SDK方法”不是我的情况。我如何测试我的API和存根调用DynamoDB？现在测试实际上正在工作，但它实际上调用了我想要避免的数据库：

const isStub = true;

const mochaPlugin = require('serverless-mocha-plugin');
const chaiExclude = require('chai-exclude');

const sinon = require('sinon');

mochaPlugin.chai.use(chaiExclude);

const expect = mochaPlugin.chai.expect;
const assert = mochaPlugin.chai.assert;

let createHandler = mochaPlugin.getWrapper('postStory', '/../../functions/create/create.js', 'handler');

const { constants } = require('core/index');

const localConstants = require('../utils/constants');

const AWS = require('aws-sdk');
const AWSMock = require('aws-sdk-mock');

describe('create', () => {

    let dynamoSpy = sinon.spy();

    before((done) => {
        if (isStub) {
            AWSMock.mock('DynamoDB.DocumentClient', 'put', dynamoSpy);
        }
        done();
    });
    after((done) => {
        if (isStub) {
            assert.isTrue(dynamoSpy.calledOnce, 'should make at least one call to DynamoDB via AWS SDK');
            AWSMock.restore('DynamoDB.DocumentClient', 'put');
            sinon.reset();
        }
        done();
    });

    it('should pass object with correct values to save', function () {
        return createHandler.run(require('../events/create/create.json')).then((response) => {
            console.log(response);
            expect(response.statusCode).to.equal(201);
        });
    });

我有同样的问题，我通过使用sinon解决它，请看看如何存根Dynamo功能，然后测试你想要的任何东西：

import {expect} from 'chai';
import * as AWS from 'aws-sdk';
import * as sinon from 'sinon';

let result = {
  // your result
}
let sinonSandbox;

beforeEach((done) => {
    sinonSandbox = sinon.createSandbox();
    done();
})

afterEach((done) => {
    sinonSandbox.restore()
    done();
})

it('your test', async () => {
    sinonSandbox.stub(AWS.DynamoDB.DocumentClient.prototype, 'put').returns({
        promise: function () {
            return Promise.resolve(result);
        }
    });

    return createHandler.run(require('../events/create/create.json')).then((response) => {
        console.log(response);
        expect(response.statusCode).to.equal(201);
    });
});

在这个例子中，我存储了promise实现，我相信你可以使用这样的回调来存储put：

sinonSandbox.stub(AWS.DynamoDB.DocumentClient.prototype, 'put').returns((params,callback) => {
    callback(null,result);
});