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Problem with React making Get request to Node(express)

As the title says, i have a part of my react app that tries to get some data from my database, making a select based on the value I passed to it. So im gonna go ahead and first show the code where i think the problem lies:
So first, this is the function from one of my forms that sends the request to the server, i know code is probably ugly, but i can tell from the console.logs that the parameters im sending are what i intend to send(a string called "licenciaInput"
async handleClickLicencia (event) {
event.preventDefault();
console.log(this.state);
console.log("licenciaInput: "+this.state.licenciaInput);
const datoBuscar = this.state.licenciaInput;
axios.get('http://localhost:3001/atletas/:licencia',this.state)
.then(response =>{
console.log(response)
})
.catch(error =>{
console.log(error)
})
And then, i have this function which is called in that localhost route which attempts to get "licencia", and launch a select in my postgresql db where licencia="whatever", you can see the sentence in the code:
const getAtletasByLicencia = (request, response) => {
const licencia = request.body.licenciaInput;
console.log("Request: "+request);
console.log("what the server gets: "+licencia);
// const licencia = request.licenciaInput;
const sentencia ="SELECT * FROM atleta WHERE licencia ='"+licencia+"'";
pool.query(sentencia, (error, results) =>{
if(error){
throw error
}
response.status(200).json(results.rows)
})
}
As you can see, i have console.logs everywhere, and i still cannot access whatever element i send, because i always get on the server console "undefined" value.
TLDR:How can i access the "licenciaInput" i passed from my client form to my server, i have tried request.body.licenciaInput, request.params.licenciaInput, and request.licenciaInput, but none of those seem to work
I also know i have to treat after that the data i receive from the server, but i need to solve this before looking two steps ahead. Im also really new to React and node/express, so feel free to burn me with good practices im not meeting.Thanks in advance
EDIT: Im also adding this code that i have which shows the route for my method in the server:
app.get('/atletas/:licencia', db.getAtletasByLicencia)
As #Gillespie59 suggested that i should send a POST request, but i dont think i should if im both trying to send a parameter to the server to make a select, and then send the results back to the client

Change your request to:
axios.get(`http://localhost:3001/atletas/${this.state.licenciaInput}`)
...
and your route (if you are using express) should look like this:
app.get('/atletas/:licencia', function (req, res) {
var licencia = req.params.licencia
...
})

As you are using request.body you should send a POST request with axios and add a body.

Can I use res.send(foo) twice?

I want to send my token and my user's role to my login.component.ts.
When I was trying to find the problem, in my research I came across someone's suggestion to use
res.write(foo1)
res.write(foo2)
res.end
Instead of
res.send(foo1)
res.send(foo2)
But that didn't work.
I then tried using this to test it:
res.write(foo1)
res.end()
But this is giving me an error:
events.js:174
throw er; // Unhandled 'error' event
^
TypeError [ERR_INVALID_ARG_TYPE]: The first argument must be one of type string or Buffer. Received type object
at write_ (_http_outgoing.js:595:11)
at ServerResponse.write (_http_outgoing.js:567:10)
at User.findOne (C:\Users\notan\GitHub\se3316-notansandwich-lab5\server\controllers\user.controller.js:46:33)
at C:\Users\notan\node_modules\mongoose\lib\model.js:4604:16
at C:\Users\notan\node_modules\mongoose\lib\query.js:4348:12
at process.nextTick (C:\Users\notan\node_modules\mongoose\lib\query.js:2850:28)
at process._tickCallback (internal/process/next_tick.js:61:11)
Emitted 'error' event at:
at C:\Users\notan\node_modules\mongoose\lib\model.js:4606:13
at C:\Users\notan\node_modules\mongoose\lib\query.js:4348:12
at process.nextTick (C:\Users\notan\node_modules\mongoose\lib\query.js:2850:28)
at process._tickCallback (internal/process/next_tick.js:61:11)
This is my user.controller.js, which I use in my route.js which is used in my sever.js
const User = require('../models/user.model')
const jwt = require('jsonwebtoken')
exports.user_create = function (req, res, next) {
let user = new User(
{
_id: Math.random().toString(36).substr(2, 5), // generate a random ID
email: req.body.email,
password: req.body.password,
firstName: req.body.firstName,
lastName: req.body.lastName,
role: "user"
}
);
user.save(function (err, registeredUser) {
if (err) {
return next(err);
}
else {
let payload = { subject: registeredUser._id}
let token = jwt.sign(payload, 'secretKey')
res.status(200).send({token})
}
})
}
exports.user_login = function (req, res, next) {
let userData = req.body
User.findOne({email: userData.email}, (err, user) => {
if (err) {
console.log(err)
}
else {
if (!user) {
res.status(401).send('Invalid email')
}
else if (user.password !== userData.password) {
res.status(401).send('Invalid password')
}
else {
let payload = {subject: user._id}
let token = jwt.sign(payload, 'secretKey')
//res.status(200).send({token})
res.status(200).write({token})
//let role = this.user.role
// res.status(200).write({role})
res.end()
}
}
})
}
Using this works
res.status(200).send({token})
But this does not
res.status(200).write({token})
res.end()

In response to the title of your question:
Can I use res.send(foo) twice?
No, you cannot call that twice for the same request.
See the second part of the answer since the OP changed their question after I wrote this first part
In Express, you can only use res.send() or res.json() or res.end() once per request. When you execute those, it sends the request. If you try to send more on the same request, it will do nothing and will show a warning in Express.
res.write() can be called more than once, then followed by res.end() when you are finally done with the request.
In your example:
res.status(200).send({token})
res.end()
The res.send() already calls .end() for you so trying to call it again is considered an error because the request has already been sent.
FYI, .status(200) is not necessary. The default status is already 200 so res.send({token}) will already have a 200 status.
More Recent Answer for the Modified Question
Now that you've completely changed the question to be about res.write({token}), that does not work because res.write() requires a String or a Buffer as an argument and you were giving it an object. You would have to manually convert the object to JSON yourself:
res.type('application/json');
res.write(JSON.stringify({token}));
res.end();
And note that this also sets the appropriate content type. If your object is large with res.write() you may also have to pay attention to the write buffer being full and listen for the drain event. res.write() is a much lower level facility (it's at the http level, not at the Express level) than the Express functions for sending data.
Built into Express, you can use res.send() or res.json() which are Express methods that will both that you passed an object, automatically convert it to JSON for you and set the content type to JSON also. It will also handle any buffer full issues in the write stream too.
res.send({token});
or, I prefer to be more explicit in my Express code with:
res.json({token});
And, if you're trying to send multiple pieces of data, you can put them into the same object:
res.json({token, role});

Calling res.status(200).send({ token }) ends the request and sends the object back to the client...
Since the request is now ended... Calling res.end() generates the error...
You'd usually use res.end if u were piping some data (usually binary) after several res.write to close the pipe...
For more info... checkout Express' docs in the response object...
https://expressjs.com/en/api.html#res
Also... U can't send an object using res.write...
From your error... it says that it inly accepts a string or buffer. If u want to send plain objects... res.send or res.json would be more appropriate...

I found the solution: I can send multiple things in an res.send(...)
res.status(200).send({token, role})

If you want to use res.write(argument) you have to pass the argument as a string or Buffer, just like the error message says. To get the same effect just convert your response object to a string:
res.status(200).write(JSON.stringify({token}))

Unit test for a sub-method which called from main method and include http-request authoraztion

I faced to a really complicated scenario, hope you guys give me a hint.
So I have a main method, which is a api endpoint, this method call another method to check if the user is authorized to use this endpoint or not.
The sub-endpoint which I called it apiAuthorazation send a get request to a thirdparty url, and this third-party return a response which says this user is authorized, or not!
So I already have a unit test for the main method, but now I want add this authorization part to it. I know I can use muck libs like Nock or other similar libraries, but my problem is how can I add this sub-method to my uit test.
This is my api endpoint method :
module.exports.api = (event, context, callback) => {
// Authorization
let getBearertoken = event.headers.Authorization.replace("Bearer ", '');
let isAuhtorized = utilities.apiAuthorazation(getBearertoken);
//Some other Codes
}
As you can see I passed a bearer token to my sub-method, and apiAuthorazation method will going to send this token to a third-party api, and the method is like this :
module.exports.apiAuthorazation = function (token){
let url = process.env.authApiUrl
requestLib(`${url}/${token}`, function (error, response, body) {
if (error) console.log('Error while checking token :', error);
if(response.isValidUser){
return true;
}
else{
return false;
}
});
}
Now my question is how can I include this sub-method to my main method unit test. I use mocha and chai for unit testing, bceause the berear token will expire soon, so when I run the test, I send a sample event which have the berear token in it, but it's already expired, so its kind of useless.

When you unit test Api, you can mock apiAuthorization for the two scenarios (true or false) and test if Api behaves as expected. Dont worry about what happens inside the sub method at all for the Api tests as you are testing Api here and the focus is not on what is happening inside the sub method, apiAuthorization.

Passing function on express js Route not working

I'm just really new on Node and Express. Trying to pass a function instead of text on my route but it seems not working. I just looked up at documentation there, They mentioned only text with req.send() method. I'm trying to pass here function's but it's not working. and also the alert() not working like this req.send(alert('Hello world')) it say's alert isn't defined or something similar.
**Update: ** I'm trying to execute this library with express and node https://github.com/przemyslawpluta/node-youtube-dl
I'm trying to do here pass functions like this
function blaBla() {
var youtubedl = require('youtube-dl');
var url = 'http://www.youtube.com/watch?v=WKsjaOqDXgg';
// Optional arguments passed to youtube-dl.
var options = ['--username=user', '--password=hunter2'];
youtubedl.getInfo(url, options, function(err, info) {
if (err) throw err;
console.log('id:', info.id);
console.log('title:', info.title);
console.log('url:', info.url);
console.log('thumbnail:', info.thumbnail);
console.log('description:', info.description);
console.log('filename:', info._filename);
console.log('format id:', info.format_id);
});
}
app.get('/', (req, res) => {
res.send(blaBla());
})
**Instead of **
app.get('/', function (req, res) {
res.send('Hello World!')
})
I hope you guy's understood my question.

res.send() expects a string argument. So, you have to pass a string.
If you want the browser to execute some Javascript, then what you send depends upon what kind of request is coming in from the browser.
If it's a browser page load request, then the browser expects an HTML response and you need to send an HTML page string back. If you want to execute Javascript as part of that HTML page, then you can embed a <script> tag inside the page and then include Javascript text inside that <script> tag and the browser will execute that Javascript when the page is parsed and scripts are run.
If the route is in response to a script tag request, then you can return Javascript text as a string and you need to make sure the MIME type appropriately indicates that it is a script.
If the route is in response to an Ajax call, then it all depends upon what the caller of the Ajax call expects. If they expect a script and are going to execute the text as Javascript, then you can also just send Javascript text as a string. If they expect HTML and are going to process it as HTML, then you probably need to embed the <script> tag inside that HTML in order to get the Javascript executed.
In your example of:
response.send(blaBla());
That will work just fine if blaBla() synchronously returns a string that is formatted properly per the above comments about what the caller is expecting. If you want further help with that, then you need to show or describe for us how the request is initiated in the browser and show us the code for the blaBla() function because the issue is probably in the blaBla() function.
There are lots of issues with things you have in your question:
You show req.send(alert('Hello world')) in the text of your question. The .send() method belongs to the res object, not the req object (the second argument, not the first). So, that would be res.send(), not req.send().
In that same piece of code, there is no alert() function in node.js, but you are trying to execute it immediately and send the result with .send(). That won't work for a bunch of reasons.
Your first code block using blaBla() will work just fine as long as blaBla() returns a string of the right format that matches what the caller expects. If that doesn't work, then there's a problem with what blaBla() is doing so we need to see that code.
Your second code block works because you are send a string which is something the caller is equipped to handle.
Update now that you've shown the code for blaBla().
Your code for blaBla() does not return anything and it's asynchronous so it can't return the result. Thus, you cannot use the structure response.send(blaBla());. There is no way to make that work.
Instead, you will need to do something different like:
blaBla(response);
And, then modify blaBla() to call response.send(someTextValue) when the response string is known.
function blaBla(res) {
var youtubedl = require('youtube-dl');
var url = 'http://www.youtube.com/watch?v=WKsjaOqDXgg';
// Optional arguments passed to youtube-dl.
var options = ['--username=user', '--password=hunter2'];
youtubedl.getInfo(url, options, function(err, info) {
if (err) {
res.status(500).send("Internal Error");
} else {
console.log('id:', info.id);
console.log('title:', info.title);
console.log('url:', info.url);
console.log('thumbnail:', info.thumbnail);
console.log('description:', info.description);
console.log('filename:', info._filename);
console.log('format id:', info.format_id);
// construct your response here as a string
res.json(info);
}
});
}
Note also that the error handling does not use throw because that is really not useful inside an async callback.

No one just could help me with that and after finding things are alone I got to know how to do this. In express there is something called middleware we have to use that thing to get this kind of matter done. Those who are really expert or have working experience with express they know this thing.
to using functions with express you need to use middleware.
like below I'm showing
const express = require('express')
const youtubedl = require('youtube-dl');
const url = 'https://www.youtube.com/watch?v=quQQDGvEP10';
const app = express()
const port = 3000
function blaBla(req, res, next) {
youtubedl.getInfo(url, function(err, info) {
console.log('id:', info.id);
console.log('title:', info.title);
console.log('url:', info.url);
// console.log('thumbnail:', info.thumbnail);
// console.log('description:', info.description);
console.log('filename:', info._filename);
console.log('format id:', info.format_id);
});
next();
}
app.use(blaBla);
app.get('/', (request, response) => {
response.send('Hey Bebs, what is going on here?');
})
app.listen(port, (err) => {
if (err) {
return console.log('something bad happened', err)
}
console.log(`server is listening on ${port}`)
})
And remember that you must need to use app.use(blaBla); on top of getting your route. Otherwise this might not work.

ExpressJS apparent race condition between Promise and EventEmitter

I have a NodeJS/Express web application that allows the user to upload a file, which I then parse using connect-busboy save to my database using Sequelize. Once that's done, I want to redirect the user to a given page. But Express is returning a status of 404 before my Promise resolves, even though I'm never calling next(), which I thought was mandatory in order to call the next handler in the middleware chain and thus result in a 404.
This is my code so far:
function uploadFormFile(req, res, next) {
var documentInstanceID = req.params.documentInstanceID;
// set up an object to hold my data
var data = {
file: null,
documentDate: null,
mimeType: null
};
// call the busboy middleware explicitly
// EDIT: this turned out to be the problem... of course this calls next()
// removing this line and moving it to an app.use() made everything work as expected
busboy(req, res, next);
req.pipe(req.busboy);
req.busboy.on('file', function (fieldName, file, fileName, encoding, mimeType) {
var fileData = [];
data.mimeType = mimeType;
file.on('data', function (chunk) {
fileData.push(chunk);
});
file.on('end', function () {
data.file = Buffer.concat(fileData);
});
});
req.busboy.on('finish', function () {
// api methods return promises from Sequelize
api.querySingle('DocumentInstance', ['Definition'], null, { DocumentInstanceID: documentInstanceID })
.then(function (documentInstance) {
documentInstance.RawFileData = data.file;
documentInstance.FileMimeType = data.mimeType;
// chaining promise
return api.save(documentInstance);
}).then(function () {
res.redirect('/app/page');
});
});
}
I can confirm that my data is being persisted correctly. But due to the race condition, the web page says 'can't POST' due to the 404 status being returned by Express, and the res.redirect is failing with an error setting the headers because it's trying to redirect after the 404 has been sent.
Can anyone help me figure out why Express is returning the 404?

The problem is coming from your internal call to busboy inside your handler. Rather than it executing and simply returning control to your handler, it would be calling the next which is passed to it before it returns control. So you code after the busboy call does execute, but the request has already advanced past that point.
In cases in which you want some middleware to only be executed for certain requests, you can chain middleware into those requests, such as:
router.post('/upload',busboy,uploadFromFile)
You can also separate them with .use() such as:
router.use('/upload', busboy);
router.post('/upload', uploadFromFile);
Either of the above will chain the middleware in the way you intended. In the case of .use() the middleware would also be applied to any applicable .METHOD() as Express refers to it in their documentation.
Also, note that you can pass in an arbitrary number of middleware this way, either as separate parameters or as arrays of middleware functions, such as:
router.post('/example', preflightCheck, logSomeStuff, theMainHandler);
// or
router.post('example', [ preflightCheck,logSomeStuff ], theMainHandler);
The execution behavior of either of the above examples will be equivalent. Speaking only for myself and not suggesting it is a best practice, I normally only use the array-based addition of middleware if i am building the middleware list at runtime.
Good luck with it. I hope you enjoy using Express as much as I have.