I want to check a case that certain routes are calling the correct controller use Jest specific (mock or spy).
It is case specific for unit testing. Somebody can help me how to check it use jest. I don't need verify kind of
expect (status code or res object) i need to check if controller have been called.
Thanks!
For instance:
// todoController.js
function todoController (req, res) {
res.send('Hello i am todo controller')
}
// index.spec.js
const express = require('express');
const request = require('request-promise');
const todoController = require('./todoController');
jest.mock('./todoController');
const app = express();
app.get('/todo', todoController)
test('If certain routes are calling the correct controller , controller should to have been called times one.', async() => {
await request({url: 'http://127.0.0.1/todo'})
expect(todoController).toHaveBeenCalledTimes(1);
})
Actually if you search, there are many references out there.
In the following, I share a few ways that I know.
One of the big conceptual leaps to testing Express applications with mocked request/response is understanding how to mock a chained
API eg. res.status(200).json({ foo: 'bar' }).
First you can make some kind of interceptor, this is achieved by returning the res instance from each of its methods:
// util/interceptor.js
module.exports = {
mockRequest: () => {
const req = {}
req.body = jest.fn().mockReturnValue(req)
req.params = jest.fn().mockReturnValue(req)
return req
},
mockResponse: () => {
const res = {}
res.send = jest.fn().mockReturnValue(res)
res.status = jest.fn().mockReturnValue(res)
res.json = jest.fn().mockReturnValue(res)
return res
},
// mockNext: () => jest.fn()
}
The Express user-land API is based around middleware. AN middleware that takes a request (usually called req), a response (usually called res ) and a next (call next middleware) as parameters.
And then you have controller like this :
// todoController.js
function todoController (req, res) {
if (!req.params.id) {
return res.status(404).json({ message: 'Not Found' });
}
res.send('Hello i am todo controller')
}
They are consumed by being “mounted” on an Express application (app) instance (in app.js):
// app.js
const express = require('express');
const app = express();
const todoController = require('./todoController');
app.get('/todo', todoController);
Using the mockRequest and mockResponse we’ve defined before, then we’ll asume that res.send() is called with the right payload ({ data }).
So on your test file :
// todo.spec.js
const { mockRequest, mockResponse } = require('util/interceptor')
const controller = require('todoController.js')
describe("Check method \'todoController\' ", () => {
test('should 200 and return correct value', async () => {
let req = mockRequest();
req.params.id = 1;
const res = mockResponse();
await controller.todoController(req, res);
expect(res.send).toHaveBeenCalledTimes(1)
expect(res.send.mock.calls.length).toBe(1);
expect(res.send).toHaveBeenCalledWith('Hello i am todo controller');
});
test('should 404 and return correct value', async () => {
let req = mockRequest();
req.params.id = null;
const res = mockResponse();
await controller.todoController(req, res);
expect(res.status).toHaveBeenCalledWith(404);
expect(res.json).toHaveBeenCalledWith({ message: 'Not Found' });
});
});
This is only 1 approach to testing Express handlers and middleware. The alternative is to fire up the Express server.
Related
I am new to Node.js and Jest unit test cases. I have tried to call Jest for controller.js. It is working for one endpoint for another endpoint the controller is making a call to service.
I have not used the mock. Direct call from Jest I have tried. But 'request.on' has not been covered from Jest. I tried all combinations but no luck. I am adding the code details below.
Please let me know how to call 'request.on' from Jest or how to make calls to Service using mock.
controller.js
'use strict'
const service = require('./service/serviceClass');
const control = {
serve: (req, res) => {
service.serve(req, res);
},
}
module.exports = control;
serviceClass.js
require("dotenv").config();
const firebase = require('firebase-admin');
let fbMap = new Map();
function fbInit(){
let fbAdmin = firebase.initializeApp({
credential: firebase.credential.cert('service.json');
});
fbMap.set('fb', fbAdmin);
}
let serve = {
serve: (req, res, next) => {
fbInit();
const body = [];
req.on('data', (chunk) => body.push(chunk))
req.on('end', () => {
const reqString = Buffer.concat(body).toString();
var id = JSON.parse(reqString).firebaseId;
if(id !=== undefined){
var fire = fbMap.get('fb');
fire.auth().getUser(id).then((user)=>{
if(user != null){
console.log("email of the user:"+user.email);
}
)};
}
}
}
}
module.exports=serve;
It would be great if I get the help to either make 'mock' calls for service or how to make the code cover for 'request.on' from Jest.
I use gRPC but I have a problem initializing the service in Next.js app.
Goal: Create client service only once in app and use it in getServerSideProps (app doesn't use client-side routing).
For example, we have a service generated with grpc-tools (only available on SSR) and then I just want to initialize it somewhere. At first I thought it can be realized in a custom server.js:
const { credentials } = require('#grpc/grpc-js');
const express = require("express");
const next = require("next");
const { MyserviceClient } = require('./gen/myservice_grpc_pb');
const dev = process.env.NODE_ENV !== "production";
const app = next({ dev });
const handle = app.getRequestHandler();
// Init & Export
exports.myService = new MyserviceClient(
'http://localhost:3000',
credentials.createInsecure(),
);
(async () => {
await app.prepare();
const server = express();
server.get("*", (req, res) => handle(req, res));
server.listen(process.env.PORT, () => {
console.log(`Listening at http://localhost:${process.env.PORT}`);
});
})();
And then use it on the homepage, for example:
import React from 'react';
const { GetSmthRequest } = require('../gen/myservice_pb');
const { myService } = require('../server.js');
const IndexPage = () => (
<div>
<span>My HomePage</span>
</div>
)
const getServerSideProps = async () => {
const request = new GetSmthRequest();
request.setSomeStuff('random');
myService.getStmh(GetSmthRequest, (err, res) => {
//...
})
return {
props: {
}
}
}
export default IndexPage;
But for some reason it's not possible to initialize the client service in the server.js.
Also I tried doing it with next.config.js:
const { credentials } = require('#grpc/grpc-js');
const { MyserviceClient } = require('./gen/myservice_grpc_pb');
module.exports = {
serverRuntimeConfig: {
myService: new MyserviceClient(
'http://localhost:3000',
credentials.createInsecure(),
),
},
};
This solution works, so I can use the service through serverRuntimeConfig, thereby initializing it only once in the entire application, but when I make a request somewhere using getServerSideProps, I get an error:
Request message serialization failure: Expected argument of type ...
Error explanation: (https://stackoverflow.com/a/50845069/9464680)
That error message indicates that message serialization
(transformation of the message object passed to gRPC into binary data)
failed. This generally happens because the message object doesn't
match the expected message type or is otherwise invalid
Does anyone know why I am getting this error?
It's also interesting to see some examples of using Next.js with grpc-node.
For such a case you can use Node.js global
I'm using Axios to query an endpoint in my backend. When I try and do this, I get a 404 not found. If I copy/paste the uri it gives in the error from the console and try and access it directly in the browser it connects fine and does not give me an error (instead giving me an empty object which is expected).
Below is my Axios code
axios.post("/api/myEndpoint", { id: this.userID })
.then((response) => {
this.property = response.data.property;
})
.catch((errors) => {
console.log(errors);
router.push("/");
});
Below is the route definition in my backend
const myEndpointRoute = require('../api/myEndpoint.js')();
exprApp.use('/api/myEndpoint', myEndpointRoute);
For reference, the uri is 'http://localhost:3000/api/myEndpoint'. I can access this uri completely fine in the browser but Axios returns a 404 as described above. It is for this reason that I'm confident this is an issue in the frontend, however I have set up this Axios request in the same way as the many others I have and they all work fine.
Edit: here's the rest of the backend
myEndpoint.js
module.exports = function() {
const express = require('express'), router = express.Router();
const authMiddleware = require('../loaders/authMiddleware.js')();
router.get('/', authMiddleware, async function(req, res) {
const id = req.body.id;
const property = await require('../services/myEndpointService.js')
(id).catch((e) => { console.log(e) });
res.send({ property: property });
});
return router;
};
myEndpointService.js
module.exports = async function(id) {
const results = await require('../models/getMyEndpointProperty')(id);
return results;
};
getMyEndpointProperty
module.exports = async function(id) {
const pool = require('../loaders/pool.js')();
const res = await pool.query(`SELECT * FROM myTable WHERE id = ${id};`);
return res.rows;
};
myEndpoint.js defines only a GET method but your axios call sends a POST in the frontend. Try changing (or adding) the express route:
// notice the `.post`
router.post('/', authMiddleware, async function(req, res) {
...
})
It worked when you manually tested it in the browser for this reason as well, since the browser sent a GET request.
I need to change a route params at runtime in nodejs.
In my code I set a route using:
const troutes = require('./src/routes/testroutes')(page,sessionId)
app.use('/teste' + sessionId, troutes)
But, in runtime, sometimes the "page" object param is recreated and it becomes invalid. But the "sessionId" param is the same, no changes.
Then I create a new "page" and need remake the route, because the old route has a invalid page.
if I use:
let page={newpage};
const troutes = require('./src/routes/testroutes')(page,sessionId);
My urls don´t work because the route use the old invalid "page" param object.
How could I delete or change the old route and use the new route with the new "page" object?
//server.js
const express = require('express')
const app = express()
const server = require('http').Server(app)
const port = 3001
const host = 'http://localhost'
const callbackUrl = `${host}:${port}`;
let page={page};
let sessionId='sessionId';
const troutes = require('./src/routes/testroutes')(page,sessionId)
app.use('/teste' + sessionId, troutes)
....
});
//routes.js
const express = require('express');
const router = express.Router();
module.exports = function (page,sessionId) {
router.get('/'+sessionId+'/getMyNumber', async (req, res) => {
const cc = await page.evaluate(() => {
return getMyNumber();
});
console.log(cc);
res.send({ "data": cc });
});
return router;
}
since you called require('./src/routes/testroutes')(page,sessionId) method only once in file, it loads only once. so passed parameters/initializations within function executed only once.
the router which is initialized and returned is used for further request processing.So new request will only trigger method of router.
if you want page to be dynamic, it would work if you move page inside router, instead of passing it from wrapper function as below.
const express = require('express');
const router = express.Router();
module.exports = function (sessionId) {
router.get('/'+sessionId+'/getMyNumber', async (req, res) => {
let page = {newPage}
const cc = await page.evaluate(() => {
return getMyNumber();
});
console.log(cc);
res.send({ "data": cc });
});
return router;
}
I have an ExpressJS routing for my API and I want to call it from within NodeJS
var api = require('./routes/api')
app.use('/api', api);
and inside my ./routes/api.js file
var express = require('express');
var router = express.Router();
router.use('/update', require('./update'));
module.exports = router;
so if I want to call /api/update/something/:withParam from my front end its all find, but I need to call this from within another aspect of my NodeJS script without having to redefine the whole function again in 2nd location
I have tried using the HTTP module from inside but I just get a "ECONNREFUSED" error
http.get('/api/update/something/:withParam', function(res) {
console.log("Got response: " + res.statusCode);
res.resume();
}).on('error', function(e) {
console.log("Got error: " + e.message);
});
I understand the idea behind Express is to create routes, but how do I internally call them
The 'usual' or 'correct' way to handle this would be to have the function you want to call broken out by itself, detached from any route definitions. Perhaps in its own module, but not necessarily. Then just call it wherever you need it. Like so:
function updateSomething(thing) {
return myDb.save(thing);
}
// elsewhere:
router.put('/api/update/something/:withParam', function(req, res) {
updateSomething(req.params.withParam)
.then(function() { res.send(200, 'ok'); });
});
// another place:
function someOtherFunction() {
// other code...
updateSomething(...);
// ..
}
This is an easy way to do an internal redirect in Express 4:
The function that magic can do is: app._router.handle()
Testing: We make a request to home "/" and redirect it to otherPath "/other/path"
var app = express()
function otherPath(req, res, next) {
return res.send('ok')
}
function home(req, res, next) {
req.url = '/other/path'
/* Uncomment the next line if you want to change the method */
// req.method = 'POST'
return app._router.handle(req, res, next)
}
app.get('/other/path', otherPath)
app.get('/', home)
I've made a dedicated middleware for this : uest.
Available within req it allows you to req.uest another route (from a given route).
It forwards original cookies to subsequent requests, and keeps req.session in sync across requests, for ex:
app.post('/login', async (req, res, next) => {
const {username, password} = req.body
const {body: session} = await req.uest({
method: 'POST',
url: '/api/sessions',
body: {username, password}
}).catch(next)
console.log(`Welcome back ${session.user.firstname}!`
res.redirect('/profile')
})
It supports Promise, await and error-first callback.
See the README for more details
Separate your app and server files with the app being imported into the server file.
In the place you want to call your app internally, you can import you app as well as 'request' from 'supertest'. Then you can write
request(app).post('/someroute').send({
id: 'ecf8d501-5abe-46a9-984e-e081ac925def',
etc....
});`
This is another way.
const app = require('express')()
const axios = require('axios')
const log = console.log
const PORT = 3000
const URL = 'http://localhost:' + PORT
const apiPath = (path) => URL + path
app.get('/a', (req, res) => {
res.json('yoy')
})
app.get('/b', async (req, res) => {
let a = await axios.get(apiPath('/a'))
res.json(a.data)
})
app.listen(PORT)