I am working on unit testing an Express application. I am trying to mock up my external dependencies (Express, database, etc) and am close to a break through.
However, I am having issues with stubs not being called from within a .then() inside my business logic.
A couple of the methods I am attempting to test are the following:
/**
* Ping
* A simple endpoint to poke for testing.
* #arg {*} request - Incoming request
* #arg {*} response - Outgoing response
* #arg {*} next - Next route in series
*/
ping: (request, response, next) => {
let elapsed = Date.now() - request.start;
response.status(200).json({
request_started: new Date(request.start).toISOString(),
request_duration: `${elapsed} milliseconds`
});
},
/**
* Registration
* Allows for registration of a user name and password.
* #arg {*} request - Incoming request
* #arg {*} response - Outgoing response
* #arg {*} next - Next route in series
*/
register: (request, response, next) => {
let username = request.body.username;
let password = request.body.password;
this.model.registerUser(username, password).then(ret => {
if (ret) {
response.status(201).send("Created");
} else {
response.status(400).send("Error processing registration request. Please try again.");
}
}).catch(err => {
response.status(400).send("Error processing registration request. Please try again.");
});
}
The model in register returns a Promise that wraps a call to a database and replies based on the outcome. I have a mock of this setup as follows:
mockModel: {
registerUser: sinon.stub().callsFake(function(user, pass) {
if (typeof user !== 'undefined') {
return Promise.resolve(pass === 'pass');
}
}),
getUser: sinon.stub().callsFake(function(user, pass) {
if (typeof user !== 'undefined' && pass === 'pass') {
return Promise.resolve({id: 9999});
} else {
return Promise.resolve(false);
}
})
}
I also have the response object mocked so I can pass it in and determine if it is called correctly:
mockRes: () => {
return {
status: sinon.stub().returnsThis(),
send: sinon.stub(),
json: sinon.stub()
};
}
The problem arises when I get to the tests:
describe('Register() method', function() {
this.beforeEach(function() {
req = mockReq(0, {}, {username: 'user', password: 'pass'});
res = mockRes();
base.BaseRoutes(router, null, base.methods, mockModel);
});
it('Returns a 201 Created message upon success', function() {
base.methods.register(req, res);
chai.expect(res.status).to.have.been.calledWith(201);
chai.expect(res.send).to.have.been.calledWith('Created');
});
});
The test here fails with the following error:
1) Base Methods
Register() method
Returns a 201 Created message upon success:
AssertionError: expected stub to have been called with arguments 201
at Context.<anonymous> (test\spec.js:50:50)
Stepping through with a debugger shows that the method is getting called, yet I'm getting this failure.
Other tests in the same suite that leverage the same mocked request/response work correctly but they don't use Promise calls (example: ping() method)
I suspect that it has something to so with scoping, but I'm not sure where things are going wrong.
After running through this a few more times, I found that it was not a scope issue, but an asynchronous issue. The test case was completing before the Promise resolved/rejected.
The piece that I was missing to close the loop was that my Express route handlers needed to return the Promise that they created to handle the database call:
register: (request, response, next) => {
let username = request.body.username;
let password = request.body.password;
return this.model.registerUser(username, password).then((ret) => {
if (ret) {
response.status(201).send("Created");
} else {
response.status(400).send("Error processing registration request. Please try again.");
}
}, (err) => {
response.status(400).send("Error processing registration request. Please try again.");
});
},
And then the test, perform my assertions in the then() on the returned Promise:
it('Returns a 201 Created message upon success', function(done) {
base.methods.register(req, res).then(x => {
chai.expect(res.status).to.have.been.calledWith(201);
chai.expect(res.send).to.have.been.calledWith('Created');
}).then(done, done);
});
it('Returns a 400 message upon failure', function(done) {
req = mockReq(0, {}, {username: 'user', password: 'fail'});
base.methods.register(req, res).then(x => {
chai.expect(res.status).to.have.been.calledWith(400);
chai.expect(res.send).to.have.been.calledWith(sinon.match.string);
}).then(done, done);
While there were examples of passing the Promise to the test and handling it there and examples on testing Express route handlers in isolation, I couldn't find examples that combined the two and tested it. Hopefully this can be of service to someone else.
Related
I am trying to create signup and Login for the first time with express and react using PostgreSQL. My post works just fine. A user can be added to the database so I jumped into handling duplicates.
I am using the findUserByEmail function to find my email and then, in my routes, create the user if it does not exist.
I tried everything and still is giving me problems. I manage to get it working by just returning the query, without a response, which I don't think is right:
const findUserByEmail = (req, response) => {
return pool.query("SELECT * FROM users WHERE email = $1", [req.body.email])
};
Although, I need the response to handle the errors.
The way that I found more common and is how I am trying is:
const findUserByEmail = (req, response) => {
pool.query("SELECT * FROM users WHERE email = $1", [req.body.email]),
(error, results) => {
if (error) {
throw error;
}
response.json(results.rows);
};
};
And when I call it here:
app.post("/signup/user", (req, res, next) => {
queries
.findUserByEmail(req, res)
.then(user => {
if (user.rows.length > 0) {
res.status(400).send("this email is already in use");
} else {
queries.createUser(req.body, res);
}
})
.catch(err => {
console.log(err);
res.status(500).send("Something went wrong");
});
});
But the error is:
Cannot read property 'then' of undefined
If anybody can give me a hand cause I've been 2/3 weeks just for the authentication.
I'll leave my repo if anybody wants to have a look, is a bit messy though.
https://github.com/jaitone/CRUD-in-JS
Thank you!
if you are using pg as part of your project. then:
const findUserByEmail = (req, response) => { // send just email instead
return pool.query("SELECT * FROM users WHERE email = $1", [req.body.email])
};
Is completely legal and beautiful. The library creates a promise and returns it.
I manage to get it working by just returning the query
It is not returning the query, it is returning the mechanism to run the query in a promise wrapper(to be run in the future). So when you do .then it will actually execute and return the result. BUT
If you want to do it manually:
In the findUserByEmail you are not returning a Promise, instead you are just ending the request chain by saying res.json(which in turn means you are returning undefined).
You can create a Promise wrapper or use util.promisfy to make the pool.query a promise.
const findUserByEmail = (req, response) => { // send just email instead
return new Promise((resolve, reject)=>{
pool.query("SELECT * FROM users WHERE email = $1", [req.body.email]),
(error, results) => {
if (error) {
reject(error);
}
resolve(results.rows);
};
});
};
Note, sending the email instead of whole req and res objects is a good idea.
I'm creating some kind of SignIn request/response in Express.
When user give valid username & password, then server will return valid authorization code.
This is code.
export const getAuthKey = async (req, res, next) => {
// Query parameter : :username, :hash(SHA256 encoded pasword)
// Return : { authKey: authKey }
if (req.query.username === undefined) { res.status(400).send('`username` query paramter missing.'); }
if (req.query.hash === undefined) { res.status(400).send('`hash` query paramter missing.'); }
getConnection()
.then(conn => new Promise((resolve, reject) => {
const escapeUserName = conn.escape(req.query.username);
const escapeSHA256 = conn.escape(req.query.hash);
return conn.query(`SELECT HEX(AuthorizationKey) AS authKey FROM UserInfo WHERE UserName = ${escapeUserName} AND UserPassword = UNHEX(${escapeSHA256});`)
.then(result => resolve(result))
.catch(err => reject(err))
.finally(() => { conn.end(); });
}))
.then(auth => {
if (auth.length < 1) { res.status(401).send('No such user found'); }
else {
log(`User ${req.query.username} requests valid authorization.`, `AUTH`)
res.json(auth[0]);
}
})
.catch(err => {
log('Unable to get authKey', 'AUTH', 'ERROR', err);
res.status(500).send(`Unable to logging-in`);
});
}
The steps are simple,
1. User send request with parameter username and hash(password)
1-1. If parameter is not fulfilled, it returns status 400.
2. Check Database and find if user is valid, if so, return it's authorization code.
3-2 If there are some unexpected error, returns status 500.
This code works. But I always see
(node:11580) UnhandledPromiseRejectionWarning: Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
I think I miss something about http request.
Can you tell me what is wrong?
Also would you provide me a code pattern for this kind of process?
p.s please ignore async on function definition.
The particular error you asked about "Cannot set headers after they are sent to the client" is caused by attempting to send a second response to the same request. So, there is typically a problem with the flow through your code that causes it to execute multiple code paths that can send a response.
On these two statements, you need to add a return statement so code does not continue executing in your function after you've sent a response:
if (req.query.username === undefined) { res.status(400).send('`username` query paramter missing.'); }
if (req.query.hash === undefined) { res.status(400).send('`hash` query paramter missing.'); }
Even though you've called res.send(), normal Javascript flow control still applies and the rest of your function will continue to execute, causing you to attempt to send another response which is the source of the "headers already sent" warning.
So, add a return to each one of these if statements to stop the function from further execution after sending the response.
if (req.query.username === undefined) {
res.status(400).send('`username` query parameter missing.');
return;
}
if (req.query.hash === undefined) {
res.status(400).send('`hash` query parameter missing.');
return;
}
I'd also suggest you modify these if statements slightly to include more conditions like empty strings:
if (!req.query.username) {
res.status(400).send('`username` query parameter missing.');
return;
}
if (!req.query.hash) {
res.status(400).send('`hash` query parameter missing.');
return;
}
FYI, also fix the spelling of "parameter".
On firebase function I need to get data from Paypal and do 4 things :
1. returns an empty HTTP 200 to them.
2. send the complete message back to PayPal using `HTTPS POST`.
3. get back "VERIFIED" message from Paypal.
4. *** write something to my Firebase database only here.
What I do now works but i am having a problem with (4).
exports.contentServer = functions.https.onRequest((request, response) => {
....
let options = {
method: 'POST',
uri: "https://ipnpb.sandbox.paypal.com/cgi-bin/webscr",
body: verificationBody
};
// ** say 200 to paypal
response.status(200).end();
// ** send POST to paypal back using npm request-promise
return rp(options).then(body => {
if (body === "VERIFIED") {
//*** problem is here!
return admin.firestore().collection('Users').add({request.body}).then(writeResult => {return console.log("Request completed");});
}
return console.log("Request completed");
})
.catch(error => {
return console.log(error);
})
As you can see when I get final VERIFIED from Paypal I try to write to the db with admin.firestore().collection('Users')..
I get a warning on compile :
Avoid nesting promises
for the write line.
How and where should I put this write at that stage of the promise ?
I understand that this HTTPS Cloud Function is called from Paypal.
By doing response.status(200).end(); at the beginning of your HTTP Cloud Function you are terminating it, as explained in the doc:
Important: Make sure that all HTTP functions terminate properly. By
terminating functions correctly, you can avoid excessive charges from
functions that run for too long. Terminate HTTP functions with
res.redirect(), res.send(), or res.end().
This means that in most cases the rest of the code will not be executed at all or the function will be terminated in the middle of the asynchronous work (i.e. the rp() or the add() methods)
You should send the response to the caller only when all the asynchronous work is finished. The following should work:
exports.contentServer = functions.https.onRequest((request, response) => {
let options = {
method: 'POST',
uri: "https://ipnpb.sandbox.paypal.com/cgi-bin/webscr",
body: verificationBody
};
// ** send POST to paypal back using npm request-promise
return rp(options)
.then(body => {
if (body === "VERIFIED") {
//*** problem is here!
return admin.firestore().collection('Users').add({ body: request.body });
} else {
console.log("Body is not verified");
throw new Error("Body is not verified");
}
})
.then(docReference => {
console.log("Request completed");
response.send({ result: 'ok' }); //Or any other object, or empty
})
.catch(error => {
console.log(error);
response.status(500).send(error);
});
});
I would suggest you watch the official Video Series on Cloud Functions from Doug Stevenson (https://firebase.google.com/docs/functions/video-series/) and in particular the first video on Promises titled "Learn JavaScript Promises (Pt.1) with HTTP Triggers in Cloud Functions".
I have some promise
getSomeInfo(data) {
return new Promise((resolve, reject) => {
/* ...some code... */
someObject.getData((err, info) => {
if (info) {
resolve(info)
}
else {
reject("Error")
}
})
})
}
I use this promise and want to send response to client from Controller (AdonisJS):
async create ({ request, response }) {
this.getSomeInfo(data).then(info => {
console.log(info) // It's work, i get the data from promise
response.status(201).json({ // but this is not work
code: 201,
message: "Data received!",
data: info
})
})
}
Why response is not work?
Simply do this.
async create ({ request, response }) {
const info = await this.getSomeInfo(data)
console.log(info)
response.status(201).json({
code: 201,
message: "Data received!",
data: info
})
}
When marking a function as async the function must return a Promise, this can be done explicitly.
async create({ request, response }) {
return this.getSomeInfo(data).then(info => {
console.log(info) // It's work, i get the data from promise
response.status(201).json({ // but this is not work
code: 201,
message: "Data received!",
data: info
})
})
}
Or implicitly using the await keyword.
async create({ request, response }) {
const info = await this.getSomeInfo(data)
console.log(info) // It's work, i get the data from promise
response.status(201).json({ // but this is not work
code: 201,
message: "Data received!",
data: info
})
}
If your console.log(info) inside of create() works and shows the data you want, but the response.status(201).json(...) does not send a response, then I can see the following possibilities:
You've already sent a response to this request (and thus cannot send another one)
The .json() method is having trouble converting info to JSON (perhaps because of circular references) and throwing an exception.
You aren't passing the arguments request and response properly and thus response isn't what it is supposed to be.
You can test for the second case like this:
create ({ request, response }) {
this.getSomeInfo(data).then(info => {
console.log(info) // It's work, i get the data from promise
response.status(201).json({ // but this is not work
code: 201,
message: "Data received!",
data: info
});
}).catch(e => {
console.log("Error in create()", e);
response.sendStatus(500);
});
}
Also, there is no reason for this method to be declared async as you don't show that you're using await or any of the features of an async function.
In the comments, you say that this function is called directly by a router (I assume an Express router). If that's the case, then the function arguments are not declared properly as they come as two separate arguments, not as properties of an object. Change the function declaration to this:
create (request, response) { ... }
I have the following route (express) for which I'm writing an integration test.
Here's the code:
var q = require("q"),
request = require("request");
/*
Example of service wrapper that makes HTTP request.
*/
function getProducts() {
var deferred = q.defer();
request.get({uri : "http://localhost/some-service" }, function (e, r, body) {
deferred.resolve(JSON.parse(body));
});
return deferred.promise;
}
/*
The route
*/
exports.getProducts = function (request, response) {
getProducts()
.then(function (data) {
response.write(JSON.stringify(data));
response.end();
});
};
I want to test that all the components work together but with a fake HTTP response, so I am creating a stub for the request/http interactions.
I am using Chai, Sinon and Sinon-Chai and Mocha as the test runner.
Here's the test code:
var chai = require("chai"),
should = chai.should(),
sinon = require("sinon"),
sinonChai = require("sinon-chai"),
route = require("../routes"),
request = require("request");
chai.use(sinonChai);
describe("product service", function () {
before(function(done){
sinon
.stub(request, "get")
// change the text of product name to cause test failure.
.yields(null, null, JSON.stringify({ products: [{ name : "product name" }] }));
done();
});
after(function(done){
request.get.restore();
done();
});
it("should call product route and return expected resonse", function (done) {
var writeSpy = {},
response = {
write : function () {
writeSpy.should.have.been.calledWith("{\"products\":[{\"name\":\"product name\"}]}");
done();
}
};
writeSpy = sinon.spy(response, "write");
route.getProducts(null, response);
});
});
If the argument written to the response (response.write) matches the test passes ok. The issue is that when the test fails the failure message is:
"Error: timeout of 2000ms exceeded"
I've referenced this answer, however it doesn't resolve the problem.
How can I get this code to display the correct test name and the reason for failure?
NB A secondary question may be, could the way the response object is being asserted be improved upon?
The problem looks like an exception is getting swallowed somewhere. The first thing that comes to my mind is adding done at the end of your promise chain:
exports.getProducts = function (request, response) {
getProducts()
.then(function (data) {
response.write(JSON.stringify(data));
response.end();
})
.done(); /// <<< Add this!
};
It is typically the case when working with promises that you want to end your chain by calling a method like this. Some implementations call it done, some call it end.
How can I get this code to display the correct test name and the reason for failure?
If Mocha never sees the exception, there is nothing it can do to give you a nice error message. One way to diagnose a possible swallowed exception is to add a try... catch block around the offending code and dump something to the console.