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How to stub a dependency in express middleware (express-validator/mocha/chai/sinon/proxyquire)

**Edit: Re-written with a simple example that works first:
So I've got a test file and 2 modules.
moduleA has a dependency, moduleB
// moduleA.js
const ModuleB = require('./moduleB');
function functionA() {
return 20 + ModuleB.functionB();
};
module.exports = { functionA };
// moduleB.js
const functionB = () => {
return 10;
}
module.exports = { functionB }
My test file stubs out functionB (returned from moduleB) using proxyquire:
const sinon = require('sinon');
const proxyquire = require('proxyquire');
describe('Unit Tests', function() {
it('should work', () => {
const mockedFn = sinon.stub();
mockedFn.returns(30);
const copyModuleA = proxyquire('./moduleA', {
'./moduleB': {
functionB: mockedFn
}
});
console.log(copyModuleA.functionA());
})
});
So it outputs 50 (stubbed functionB 30 + functionA 20)
Now I'm trying to take this example into my code:
moduleA in this case is a file called validation.js. It is dependent on moduleB, in this case a sequelize model, Person, with the function I want to mock: findOne
validation.js exports module.exports = { validateLogin };, a function that calls validate, which returns a function that uses Person.findOne()
So in my mind, as with the simple example, I need to create a stub, point to the validation module in proxyquire, and reference the dependency and its findOne function. Like this:
const stubbedFindOne = sinon.stub();
stubbedFindOne.resolves();
validationModule = proxyquire('../../utils/validation', {
'../models/Person': {
findOne: stubbedFindOne
}
});
This should stub Person.findOne in validation.js. But it doesn't seem to. And I have no idea why.
let validationModule;
describe('Unit Tests', () => {
before(() => {
const stubbedFindOne = sinon.stub();
stubbedFindOne.resolves();
validationModule = proxyquire('../../utils/validation', {
'../models/Person': {
findOne: stubbedFindOne
}
});
})
it.only('should return 422 if custom email validation fails', async() => {
const wrongEmailReq = { body: {email: 'nik#hotmail.com'} };
const res = {
statusCode: 500,
status: (code) => {this.statusCode = code; return this},
};
const validationFn = validationModule.validateLogin();
const wrongEmail = await validationFn(wrongEmailReq, res, ()=>{});
expect(wrongEmail.errors[0].msg).to.be.equal('Custom Authorisation Error');
return;
})
And this is my validation.js file:
const Person = require('../models/Person');
// parallel processing
const validate = validations => {
return async (req, res, next) => {
await Promise.all(validations.map(validation => validation.run(req)));
const errors = validationResult(req);
if (errors.isEmpty()) {
return next();
}
const error = new Error();
error.message = process.env.NODE_ENV === 'development'? 'Validation Failed':'Error';
error.statusCode = !errors.isEmpty()? 422:500;
error.errors = errors.array({onlyFirstError: true});
next(error);
return error;
};
};
const validateLogin = () => {
const validations = [
body('email')
.isString()
// snip
.custom(async (value, {req}) => {
try{
const person = await Person.findOne({ where: { email: value } });
if(!person) return Promise.reject('Custom Authorisation Error');
} catch(err) {
throw err;
}
})
.trim(),
];
return validate(validations);
}
module.exports = {
validateLogin
};

So the code in both the small sample and my app is correct, apart from how I stub the function. It shouldn't resolve or reject anything (I tried both out of desperation). It should return null in order to satisfy the conditional rather than jump to the catch block:
try{
const person = await Person.findOne({ where: { email: value } });
if(!person) return Promise.reject('Custom Authorisation Error');
} catch(err) {
throw err;
}
Hope the simple example helps someone else with proxyquire though

How to test firebase callable function with firestore

I have a firebase callable function like
exports.getUserInfo = functions.https.onCall(async (data, context) => {
const userIdRef = store.collection('UserID').doc('Document');
let res = null;
try {
res = await store.runTransaction(async t => {
const doc = await t.get(userIdRef);
currentUserId = doc.data().ID;
const newUserIdNum = currentUserId + 1;
await t.update(userIdRef, {ID: newUserIdNum});
let initUserData = {
'userID': newUserId,
}
return initUserData ;
});
console.log('Transaction success');
} catch (e) {
console.error('Transaction failure:', e);
}
return res;
})
but I am not sure how to create unit test about this. I want to mock UserID/Documment before I call
test.wrap(getUserInfo), like
const myFunctions = require('../index.js')
const getUserInfoWrapped = test.wrap(myFunctions.getUserInfo);
var assert = require('assert');
describe('User', function() {
describe('getUserInfo()', function() {
it('should create user', async function() {
// sample code, this won't work
const snapshot = test.firestore.makeDocumentSnapshot({ID: 1001}, 'UserID/Document');
const data = {}
const result = await getUserInfoWrapped (data, {});
assert.equal(result.userID, "1002");
});
});
});
seems this case not covered by firebase document
Reference:
https://firebase.google.com/docs/functions/unit-testing
https://github.com/firebase/firebase-functions-test/blob/c77aa92d345b8e4fb5ad98534989eb8dcf7d9bc4/spec/providers/https.spec.ts

Protractor - Failed: prop is not defined

Help please to find an error. I'm learning Protractor and try to create a simple test with Page Object.
//login_pageObject.js
let loginContainer = function() {
this.usernameInput = $("input.login-form-01");
this.passwordInput = $("input#login-form-02");
this.loginBtn = $("input.btn");
this.get = function() {
browser.get("https://www.cosmedicalsupplies.com/login.html");
};
this.setUsername = function(username) {
usernameInput.sendKeys(username);
};
this.setPassword = function(password) {
passwordInput.sendKeys(password);
};
this.clickOnLoginBtn = function() {
loginBtn.click();
};
};
module.exports = new loginContainer();
And
//login.js
let loginPage = require('../page_objects/login_pageObject.js');
describe('login_logout autotests', () => {
beforeEach(() => {
browser.ignoreSynchronization = true;
});
it("should sign in", () => {
loginPage.get();
loginPage.setUsername("test1");
loginPage.setPassword("test2");
loginPage.clickOnLoginBtn();
//expect.....
});
});
So, when I run this code, I have a "Failed: usernameInput is not defined" error. Where is mistake?

You need to refer to it as this.usernameInput.

How to pull out handler using module exports?

I am building a node application, and trying to neatly organize my code. I wrote a serial module that imports the serial libs and handles the connection. My intention was to write a basic module and then reuse it over and over again in different projects as needed. The only part that changes per use is how the incoming serial data is handled. For this reason I would like to pull out following handler and redefine it as per the project needs. How can I use module exports to redefine only this section of the file?
I have tried added myParser to exports, but that gives me a null and I would be out of scope.
Handler to redefine/change/overload for each new project
myParser.on('data', (data) => {
console.log(data)
//DO SOMETHING WITH DATA
});
Example usage: main.js
const serial = require('./serial');
const dataParser = require('./dataParser');
const serial = require('./serial');
//call connect with CL args
serial.connect(process.argv[2], Number(process.argv[3]))
serial.myParser.on('data',(data) => {
//Do something unique with data
if (dataParser.parse(data) == 0)
serial.send('Error');
});
Full JS Module below serial.js
const SerialPort = require('serialport');
const ReadLine = require('#serialport/parser-readline');
const _d = String.fromCharCode(13); //char EOL
let myPort = null;
let myParser = null;
function connect(port, baud) {
let portName = port || `COM1`;
let baudRate = baud || 115200;
myPort = new SerialPort(portName, {baudRate: baudRate})
myParser = myPort.pipe(new ReadLine({ delimiter: '\n'}))
//Handlers
myPort.on('open', () => {
console.log(`port ${portName} open`)
});
myParser.on('data', (data) => {
console.log(data)
});
myPort.on('close', () => {
console.log(`port ${portName} closed`)
});
myPort.on('error', (err) => {
console.error('port error: ' + err)
});
}
function getPorts() {
let portlist = [];
SerialPort.list((err, ports) => {
ports.forEach(port => {
portlist.push(port.comName)
});
})
return portlist;
}
function send(data) {
myPort.write(JSON.stringify(data) + _d, function (err) {
if (err) {
return console.log('Error on write: ', err.message);
}
console.log(`${data} sent`);
});
}
function close() {
myPort.close();
}
module.exports = {
connect, getPorts, send, close
}

The problem is that a module is used where a class or a factory would be appropriate. myParser cannot exist without connect being called, so it doesn't make sense to make it available as module property, it would be unavailable by default, and multiple connect calls would override it.
It can be a factory:
module.exports = function connect(port, baud) {
let portName = port || `COM1`;
let baudRate = baud || 115200;
let myPort = new SerialPort(portName, {baudRate: baudRate})
let myParser = myPort.pipe(new ReadLine({ delimiter: '\n'}))
//Handlers
myPort.on('open', () => {
console.log(`port ${portName} open`)
});
myParser.on('data', (data) => {
console.log(data)
});
myPort.on('close', () => {
console.log(`port ${portName} closed`)
});
myPort.on('error', (err) => {
console.error('port error: ' + err)
});
function getPorts() {
let portlist = [];
SerialPort.list((err, ports) => {
ports.forEach(port => {
portlist.push(port.comName)
});
})
return portlist;
}
function send(data) {
myPort.write(JSON.stringify(data) + _d, function (err) {
if (err) {
return console.log('Error on write: ', err.message);
}
console.log(`${data} sent`);
});
}
function close() {
myPort.close();
}
return {
myParser, getPorts, send, close
};
}
So it could be used like:
const serial = require('./serial');
const connection = serial(...);
connection.myParser.on('data',(data) => {
//Do something unique with data
if (dataParser.parse(data) == 0)
connection.send('Error');
});

How to assert that a function is called with multiple arguments

I'm learning double tests with a simple example:
const Database = require('./Database')
const setupNewUser = (info, callback) => {
const user = {
name: info.name,
nameLowercase: info.name.toLowerCase()
}
try {
Database.save(user, callback)
} catch (err) {
callback(err)
}
}
module.exports = setupNewUser
I have a function that takes an object and a callback:
const Database = {
save: (user, callback) => {
callback(user)
}
}
module.exports = Database
How can test that save is called with both an object and a callback. Below is what I'm trying:
it('it calls Database.save with a callback', () => {
const saveSpy = sinon.spy(Database, 'save')
const arg = {
name: info.name,
nameLowercase: info.name.toLowerCase()
}
setupNewUser(info, function() {})
//I'm able to assert that save is called with arg sinon.assert.calledWith(saveSpy, arg)
sinon.assert.calledWith(saveSpy, arg, function() {}) //This is failing
})

You should .stub your API calls vs .spy. I would also recommend using sinon.sandbox so your test cleanup is easy to manage. Read about it here
describe('Setup new user', function() {
const sandbox = sinon.createSandbox();
afterEach(function() {
sandbox.restore();
});
it('should call Database.save with a callback', function(){
const databaseSaveStub = sandbox.stub(Database, 'save');
const user = {
name: 'Some Name',
nameLowercase: 'some name'
};
const callbackFn = sandbox.spy();
setupNewUser(user, callbackFn);
sinon.assert.calledOnce(Database.save);
sinon.assert.calledWith(databaseSaveStub, user, callbackFn);
});
});