I have been attempting to respond to a client-side request with Node.JS. I have discovered Node JS - call function on server from client javascript, which seems to explain what I want, except that I can't seem to translate it to my program.
Here is the request via POST in index.html:
$.post("/", {data: 'hi'}, function(result){
$("body").html(result);
});
what I was hoping it would do would be write the result of the call, from my server.js (Node):
const express = require('express');
const path = require('path');
const http = require('http');
const fs = require('fs');
function handler(data, app){
if(req.method == "POST"){
app.setHeader('Content-Type', 'text/html');
app.writeHead(200);
app.end(data);
}
}
const BUILDPATH = path.join(__dirname);
const { PORT = 3000 } = process.env;
const app = express();
app.set('port', PORT);
app.use(express.static(BUILDPATH));
app.get('/*', (req, res) => res.sendFile('static/index.html', { root: BUILDPATH }));
const httpServer = http.createServer(app);
httpServer.listen(PORT);
console.info(`🚀 Client Running on: http://localhost:${PORT}`);
try this code:
const express = require('express');
const path = require('path');
const http = require('http');
const fs = require('fs');
function handler(data, app){
if(req.method == "POST"){
app.setHeader('Content-Type', 'text/html');
app.writeHead(200);
app.end(data);
}
}
const BUILDPATH = path.join(__dirname);
const { PORT = 3000 } = process.env;
const app = express();
app.set('port', PORT);
app.use(express.static(BUILDPATH));
app.get('/', (req, res) => {
res
// best practice is to always return an status code
.status(200)
// just return an json object
.json({"msg": "ok, it all works just fine"})
});
const httpServer = http.createServer(app);
httpServer.listen(PORT);
console.info(`🚀 Client Running on: http://localhost:${PORT}`);
The issue is, is that the only route your Node server listens to is the one you define with /*. As you can see, that route returns your index.html file to the client. You did not specify a route that listens for a request that comes from the client.
To solve the issue, you will have to define a route that listens on a specific route for the request you are trying to make from your client.
I see you are using ExpressJS. here is the documentation on writing routes.
Related
I'm trying to get HTTPS working on express.js for node, and it won't run.
This is my server.js code.
const fs = require('fs');
const http = require ('http');
const https = require('https');
const options = {
pfx: fs.readFileSync('ssl/pfxfile.pfx'),
passphrase: 'password'
};
const express = require('express');
const app = express();
const path = require('path');
app.use(express.json());
app.use(express.static("express"));
app.use('/', function(req,res){
res.sendFile(path.join(__dirname+'/express/index.html'));
});
var httpServer = http.createServer(app);
var httpsServer = https.createServer(options, app);
httpServer.listen(8080);
httpsServer.listen(8443);
When I run it reports no errors but it just get stuck to nothing (I waited 30 minutes to see if it does something and nothing happened).
httpServer.listen(8080, ()=>{console.log('Server is running')});
If the server successfully started, it should output "Server is running" in the console. This is a nice way to check if the server is working as intended.
I found my error, thanks for your answers, it's been helping me, my error was first that I didn't put any console.log and the second was that I was not typing 8443 in the browser.
const fs = require('fs');
const http = require('http');
const https = require('https');
const options = {
pfx: fs.readFileSync('ssl/pfxfile.pfx'),
passphrase: 'password'
};
const express = require('express');
const app = express();
const path = require('path');
app.use(express.json());
app.use(express.static("express"));
app.use('/', function(req,res){
res.sendFile(path.join(__dirname+'/express/index.html'));
});
const httpServer = http.createServer(app);
const port = process.env.PORT || 8080;
const httpsServer = https.createServer(options, app);
const portHttps = process.env.PORT || 8443;
httpServer.listen(port, () => console.log('Http listening on port ' + port));
httpsServer.listen(portHttps, () => console.log('Https listening on port ' + portHttps));
So i have made a simple express app, but i have been trying for several hours to get a response to a simple get request when i visit http://localhost:3000/
This is my app.js
// IMPORTS
const express = require('express')
const mongoose = require('mongoose')
const customerRouter = require('./routes/customerRoute.js')
const app = express()
const PORT = 3000
// CONNECTION
mongoose.connect('mongodb://localhost/Customers', {useUnifiedTopology: true })
mongoose.connection.on('open', () => {console.log('Connected to database.')})
//APP USE ROUTES AND JSON
app.use(express.json)
app.use('/customers',customerRouter)
app.get('/', (req, res) => {
res.send('Home')
})
// APP PORT SET
app.listen(PORT)
console.log('Server started on port 3000')
This is my routes file
const express = require('express')
const router = express.Router()
console.log('into the router')
router.get('/', (req, res) => {
console.log('GET request')
})
module.exports = router
Substitute app.use(express.json) with app.use(express.json()) and everything will work. You have a mistake in this middleware that parses incoming requests with JSON payloads.
Source: express docs
You made a mistake in middleware app.use(express.json()) is a function not a property of the express object.
I am trying to download array of objects in .csv format. below is the code snippet which converts an array to .csv and get stored in the file file.csv.
let downloadHelper = function(records){
let csvwriter = require('csv-writer');
createCsvWriter = csvwriter.createObjectCsvWriter;
const csvWriter = createCsvWriter({
path: './file.csv'
csvWriter.writeRecords(records).then(() => {
console.log('Done');
});
}
I need to download the file.csv to my local. tried using requests, didn't help as it is accepting only http requests. no clue, how to proceed..... Please help
You did not provide us a lot of information. But with Express you could do:
app.get("/", (req, res) => {
res.download("./file.csv", "your-custom-name.csv");
});
If this does not help you, please provide more info about the context, framework you are using and what front.
Thank you
For example, you can use Express like this:
// Libs
const express = require('express');
const http = require('http');
const path = require('path');
// Setup
const port = 8080;
const app = express();
const httpServer = http.createServer(app);
// http://localhost:8080/download
app.get('/download', (req, res) => {
res.sendFile(path.resolve(__dirname, './file.csv'));
});
// http://localhost:8080/csv/file.csv
app.use('/csv', express.static(path.resolve(__dirname, './csv_files/')));
// Run HTTP server
httpServer.listen(port, () => console.log('Server is listening on *:' + port));
If you run this snippet, you can open http://localhost:8080/download and ./file.csv would be downloaded.
Following part of code is responsible for that:
app.get('/download', (req, res) => {
res.sendFile(path.resolve(__dirname, './file.csv'));
});
Or if you want to give access to the whole directory ./csv_files/ you can do this:
app.use('/csv', express.static(path.resolve(__dirname, './csv_files/')));
Just create ./csv_files/foo.csv file and go to http://localhost:8080/csv/foo.csv.
Does it make sense to you?
PS Working example:
// Libs
const express = require('express');
const http = require('http');
const path = require('path');
const fs = require('fs');
// Setup
const port = 8080;
const app = express();
const httpServer = http.createServer(app);
// http://localhost:8080/download
app.get('/download', (req, res) => {
const filename = path.resolve(__dirname, './file' + (new Date()).getTime() + '.csv');
fs.writeFileSync(filename, 'foo,bar,baz');
res.sendFile(filename);
});
httpServer.listen(port, () => console.log('Server is listening on *:' + port));
I'm trying to use io.sockets.on inside a route in a Node.js and Express app. I have been following what is said here: https://stackoverflow.com/a/31277123/8271839
I can successfully send io.sockets.emit events, but I cannot receive events with io.sockets.on.
Here is my code:
index.js:
const cors = require('cors');
const express = require('express');
const app = express();
const server = require('http').Server(app);
const io = require('socket.io')(server);
const taskRequest = require('./routes/taskRequest');
app.use(cors())
app.use(express.json());
app.use('/api/taskRequest', taskRequest);
app.set('socketio', io);
server.listen(4002);
io.sockets.on("connection",function(socket){
console.log("connected");
socket.on("connected", function (data) {
console.log("hello");
})
});
routes/taskRequest.js:
const express = require('express');
const router = express.Router();
router.post('/', async (req, res) => {
var io = req.app.get('socketio');
//pickedUser is one of the connected client
var pickedUser = "JZLpeA4pBECwbc5IAAAA";
//we only send the emit event to the pickedUser
io.to(pickedUser).emit('taskRequest', req.body);
io.on('connection', function (socket) {
console.log('connected 2');
socket.on('taskResponse', function () {
console.log('hello 2');
});
});
});
module.exports = router;
When a client is connected, I get the "connected" message in console, but not the "connected 2" message.
Also, when client emits "connected" message, I get "hello" in console, but when clients emits "taskResponse" message, I don't get "hello 2" in console.
Though when io.to(pickedUser).emit('taskRequest', req.body); is called, it works, client receives the "taskRequest" message.
Why is .emit() working inside my route but not .on() ?
According to you code, io is a Socket.IO server instance attached to an instance of http.Server listening for incoming events. Then inside the route you are again attaching a instance to listen to to incoming events which does not work. the io.to(pickedUser).emit works because the server instance with socketio is correctly listening to the connection thus giving the console.log("connected");.
index.js:
const cors = require('cors');
const express = require('express');
const app = express();
const server = require('http').Server(app);
const io = require('socket.io')(server);
const taskRequest = require('./routes/taskRequest');
app.use(cors())
app.use(express.json());
app.use('/api/taskRequest', taskRequest);
app.set('socketio', io);
server.listen(4002);
routes/taskRequest.js:
const express = require('express');
const router = express.Router();
router.post('/', async (req, res) => {
var io = req.app.get('socketio');
//pickedUser is one of the connected client
var pickedUser = "JZLpeA4pBECwbc5IAAAA";
io.on('connection', function (socket) {
console.log('connected 2');
io.to(pickedUser).emit('taskRequest', req.body);
socket.on('taskResponse', function () {
console.log('hello 2');
});
});
});
module.exports = router;
I mark TRomesh answer as the right answer, since indeed you can only have one io.on('connection', function (socket) {}) in your code.
Now here is what I have done to make it work for me: the issue was that if you place io.on('connection', function (socket) {}) within your router.post('/', async (req, res) => {}), it will only be triggered when you call your endpoint. In my case, I had some sockets events that I wanted to be called at anytime, not only when the endpoint is called. So I had to place the io.on('connection', function (socket) {}) outside of my router.post('/', async (req, res) => {}). Thus I couldn't use var io = req.app.get('socketio'); inside the router. Here is what I have done instead:
index.js:
const cors = require('cors');
const express = require('express');
const app = express();
const server = require('http').Server(app);
const io = require('socket.io')(server);
const taskRequest = require('./routes/taskRequest')(io);
app.use(cors())
app.use(express.json());
app.use('/api/taskRequest', taskRequest);
server.listen(4002);
routes/taskRequest.js
const express = require('express');
const router = express.Router();
module.exports = function(io) {
//we define the variables
var sendResponse = function () {};
io.sockets.on("connection",function(socket){
// Everytime a client logs in, display a connected message
console.log("Server-Client Connected!");
socket.on('connected', function(data) {
//listen to event at anytime (not only when endpoint is called)
//execute some code here
});
socket.on('taskResponse', data => {
//calling a function which is inside the router so we can send a res back
sendResponse(data);
})
});
router.post('/', async (req, res) => {
//pickedUser is one of the connected client
var pickedUser = "JZLpeA4pBECwbc5IAAAA";
io.to(pickedUser).emit('taskRequest', req.body);
sendResponse = function (data) {
return res.status(200).json({"text": "Success", "response": data.data});
}
});
return router;
};
I'm trying to configure my express server to use HTTPS but I am running into some issues. I followed the documentation to setup my HTTPS server but I am still encountering some errors.
Here's my app.js
var express = require('express');
var app = express();
var server = require('https').createServer(options, app);
var io = require('socket.io')(server);
var port = process.env.PORT || 3000;
var fs = require('fs');
var options = {
key: fs.readFileSync('/test/key.pem'),
cert: fs.readFileSync('/test/cert.pem')
};
server.listen(port, function () {
console.log('Server listening at port %d', port);
});
When starting my server I encounter
https.js:32
if (process.features.tls_npn && !opts.NPNProtocols) {
^
TypeError: Cannot read property 'NPNProtocols' of undefined
at new Server (https.js:32:40)
at Object.exports.createServer (https.js:56:10)
So, I tried to define NPNProtocols within options, but that did not work. Anyone have any pointers here?
Thank you.
try this once, i think you should have certificate in .crt format. and you will require tls module.
var sslOptions = {
key: fs.readFileSync('public/server.key'),
cert: fs.readFileSync('public/server.crt')
};
tls.createServer(sslOptions, function (cleartextStream) {
var cleartextRequest = net.connect({
port: port,
host: serverStr
}, function () {
cleartextStream.pipe(cleartextRequest);
cleartextRequest.pipe(cleartextStream);
});
}).listen(443);
port is you http port . and sercerStr is you server address.
IMO, the issue is not with the extension of the keys, rather the ssl configuration used. Use https node module with correct ssl options for ca, cert, and key to enable https with express.
// server/index.js
const express = require('express');
const fse = require('fs-extra');
const helmet = require('helmet');
const https = require('https');
const path = require('path');
// path to cert files
const paths = {
certFile: '/path/to/cert.pem',
chainFile: '/path/to/fullchain.pem',
privateFile: '/path/to/privkey.pem',
};
/* Express implementation (ignore) */
const app = express();
app.use(helmet());
app.use(express.static(path.join(__dirname, '..')));
app.get('/', (request, response) => {
response.sendFile(path.join('index.html'));
});
// setup https
const setupHttps = () => {
const promises = [
fse.readFile(paths.chainFile),
fse.readFile(paths.privateFile),
fse.readFile(paths.certFile),
];
return Promise
.all(promises)
.then(data => {
const [ chainData, privateData, certData ] = data;
const options = {
ca: chainData.toString('utf-8'),
cert: certData.toString('utf-8'),
key: privateData.toString('utf-8'),
};
return https.createServer(
options,
app
).listen(443);
})
.catch(err => console.log(err));
};
return setupHttps();
EDIT: I used helmetjs for better security with http headers.