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Connection resets after 60 seconds in node.js upload application

I've written an application in node.js consisting of a server and a client for storing/uploading files.
For reproduction purposes, here's a proof of concept using a null write stream in the server and a random read stream in the client.
Using node.js 12.19.0 on Ubuntu 18.04. The client depends on node-fetch v2.6.1.
The issue I have is after 60 seconds the connection is reset and haven't found a way to make this work.
Any ideas are appreciated.
Thank you.
testServer.js
// -- DevNull Start --
var util = require('util')
, stream = require('stream')
, Writable = stream.Writable
, setImmediate = setImmediate || function (fn) { setTimeout(fn, 0) }
;
util.inherits(DevNull, Writable);
function DevNull (opts) {
if (!(this instanceof DevNull)) return new DevNull(opts);
opts = opts || {};
Writable.call(this, opts);
}
DevNull.prototype._write = function (chunk, encoding, cb) {
setImmediate(cb);
}
// -- DevNull End --
const http = require('http');
const server = http.createServer();
server.on('request', async (req, res) => {
try {
req.socket.on('end', function() {
console.log('SOCKET END: other end of the socket sends a FIN packet');
});
req.socket.on('timeout', function() {
console.log('SOCKET TIMEOUT');
});
req.socket.on('error', function(error) {
console.log('SOCKET ERROR: ' + JSON.stringify(error));
});
req.socket.on('close', function(had_error) {
console.log('SOCKET CLOSED. IT WAS ERROR: ' + had_error);
});
const writeStream = DevNull();
const promise = new Promise((resolve, reject) => {
req.on('end', resolve);
req.on('error', reject);
});
req.pipe(writeStream);
await promise;
res.writeHead(200);
res.end('OK');
} catch (err) {
res.writeHead(500);
res.end(err.message);
}
});
server.listen(8081)
.on('listening', () => { console.log('Listening on port', server.address().port); });
testClient.js
// -- RandomStream Start --
var crypto = require('crypto');
var stream = require('stream');
var util = require('util');
var Readable = stream.Readable;
function RandomStream(length, options) {
// allow calling with or without new
if (!(this instanceof RandomStream)) {
return new RandomStream(length, options);
}
// init Readable
Readable.call(this, options);
// save the length to generate
this.lenToGenerate = length;
}
util.inherits(RandomStream, Readable);
RandomStream.prototype._read = function (size) {
if (!size) size = 1024; // default size
var ready = true;
while (ready) { // only cont while push returns true
if (size > this.lenToGenerate) { // only this left
size = this.lenToGenerate;
}
if (size) {
ready = this.push(crypto.randomBytes(size));
this.lenToGenerate -= size;
}
// when done, push null and exit loop
if (!this.lenToGenerate) {
this.push(null);
ready = false;
}
}
};
// -- RandomStream End --
const fetch = require('node-fetch');
const runSuccess = async () => { // Runs in ~35 seconds
const t = Date.now();
try {
const resp = await fetch('http://localhost:8081/test', {
method: 'PUT',
body: new RandomStream(256e6) // new RandomStream(1024e6)
});
const data = await resp.text();
console.log(Date.now() - t, data);
} catch (err) {
console.warn(Date.now() - t, err);
}
};
const runFail = async () => { // Fails after 60 seconds
const t = Date.now();
try {
const resp = await fetch('http://localhost:8081/test', {
method: 'PUT',
body: new RandomStream(1024e6)
});
const data = await resp.text();
console.log(Date.now() - t, data);
} catch (err) {
console.warn(Date.now() - t, err);
}
};
// runSuccess().then(() => process.exit(0));
runFail().then(() => process.exit(0));

I tried (unsuccessfully) to reproduce what you are seeing based on your code example. Neither the success call is completing in ~35 seconds nor is the error being thrown in 60 seconds.
However, that being said, I think what is happening here is that your client is terminating the request.
You can increase the timeout by adding a httpAgent to the fetch PUT call. You can then set a timeout in the httpAgent.
const http = require('http');
...
const runFail = async () => { // Fails after 60 seconds
const t = Date.now();
try {
const resp = await fetch('http://localhost:8081/test', {
method: 'PUT',
body: new RandomStream(1024e6),
agent: new http.Agent({ keepAlive: true, timeout: 300000 })
});
const data = await resp.text();
console.log(Date.now() - t, data);
} catch (err) {
console.warn(Date.now() - t, err);
}
};
See the fetch docs for adding a custom http(s) agent here
See options for creating http(s) agent here

This turned out to be a bug in node.js
Discussion here: https://github.com/nodejs/node/issues/35661

node js child process timeout

Need to know, how can I tackle the child process problem in Node JS. Basically, I need to convert the full pdf file into a jpeg. My process is getting killed. Most of the time files conversion is getting failed. How can I handle the long-running process? once the job is finished. I need to add there reference in the database. Could you please help.
const path = require('path');
const cp = require('child_process');
const src = path.join(__dirname, `/pdf-inputs/git.pdf`);
const exp = path.join(__dirname, `/jpg-outputs/git/git-%2d.jpg`);
const density = 300;
class Converter {
constructor(src, exp, den) {
this.src = src;
this.exp = exp;
this.density = den;
}
start() {
return new Promise((resolve, reject) => {
const child = cp.spawn('convert', ['-density', '300', `${this.src}`, `${this.exp}`], {
detached: true,
stdio: 'ignore',
});
console.log('process started =======> ', this)
child.stdout.on('data', data => {
console.log('process sucessful =======> ')
return resolve (data);
});
child.stderr.on('data', err => {
console.log('imagemagic process failed =======> ')
return reject(err);
})
child.on('error', (err) => {
console.log('child process error ========> ', err);
})
child.on('exit', (code, signal) => {
console.log(`child process exited with code: ${code} and signal ${signal}`)})
})
}
}
const c = new Converter(src, exp, density);
c.start().then(r => console.log('r ==> ', r)).catch(e => console.log('e ==> ', e));
~ Meet

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');
});

Error: Cloud Functions for Firebase spawn EACCES (ghostscript)

I tried using Firebase Cloud Functions to create a thumbnail of a PDF file.
After the call of gs I get the following error:
2018-06-12T11:29:08.685Z E makeThumbnail: Error: spawn EACCES
at exports._errnoException (util.js:1020:11)
at ChildProcess.spawn (internal/child_process.js:328:11)
at exports.spawn (child_process.js:370:9)
at Object.exec (/user_code/node_modules/gs/index.js:86:28)
at Promise (/user_code/index.js:95:12)
at mkdirp.then.then (/user_code/index.js:86:12)
2018-06-12T11:29:08.698166767Z D makeThumbnail: Function execution took 780 ms, finished with status: 'error'
Is it necessary to use a component like ghostscript to use a plan other than Spark?
In addition, my code. Maybe I just do not see my problem in the code
const functions = require('firebase-functions');
const mkdirp = require('mkdirp-promise');
const gcs = require('#google-cloud/storage')();
const admin = require('firebase-admin');
const spawn = require('child-process-promise').spawn;
const path = require('path');
const os = require('os');
const fs = require('fs');
const gs = require('gs');
const THUMB_MAX_HEIGHT = 200;
const THUMB_MAX_WIDTH = 200;
const THUMB_PREFIX = 'thumb_';
const gs_exec_path = path.join(__dirname, './lambda-ghostscript/bin/gs');
try{admin.initializeApp(functions.config().firebase); } catch(e) {}
exports.makeThumbnail = functions.storage.object().onFinalize((object) => {
const filePath = object.name;
const contentType = object.contentType;
const fileDir = path.dirname(filePath);
const fileName = path.basename(filePath);
const thumbFilePath = path.normalize(path.join(fileDir, `${THUMB_PREFIX} ${fileName}`));
const tempLocalFile = path.join(os.tmpdir(), filePath);
const tempLocalDir = path.dirname(tempLocalFile);
const tempLocalThumbFile = path.join(os.tmpdir(), thumbFilePath);
const tmp_dir = os.tmpdir();
if (fileName.startsWith(THUMB_PREFIX)) {
console.log('Is thumbnail');
return null;
}
const bucket = gcs.bucket(object.bucket);
const file = bucket.file(filePath);
const thumbFile = bucket.file(thumbFilePath);
const metadata = {
contentType: contentType,
};
return mkdirp(tmp_dir).then(() => {
console.log("Dir Created");
console.log(tempLocalFile);
return file.download({destination: tempLocalFile});
}).then(() => {
console.log("File downloaded");
if(!contentType.startsWith("image/")){
return new Promise((resolve, reject) => {
const pg= 1;
gs().batch().nopause()
.option(`-dFirstPage=${pg}`)
.option(`-dLastPage=${pg}`)
.executablePath(gs_exec_path)
.device('png16m')
.output(tempLocalThumbFile+".png")
.input(tempLocalFile)
.exec(err => err ? reject(err) : resolve());
});
}
else
{
var args = [ tempLocalFile, '-thumbnail', `${THUMB_MAX_WIDTH}x${THUMB_MAX_HEIGHT}>`, tempLocalThumbFile ];
return spawn('convert', args, {capture: ['stdout', 'stderr']});
}
}).then(() => {
return bucket.upload(tempLocalThumbFile, { destination: thumbFilePath });
}).then(() => {
fs.unlinkSync(tempLocalFile);
fs.unlinkSync(tempLocalThumbFile);
return result[0];
});
});

After hours of scratching my head and running same code over and over again pointlessly, I've finally found the problem!
The executable path that you've defined is not correct. It should be 'gs'.
Here's a complete gs() call sample:
gs()
.batch()
.option('-dFirstPage=2')
.option('-dLastPage=2')
.nopause()
.res(90)
.executablePath('gs')
.device('jpeg')
.output(tempNewPath2)
.input(tempFilePath)
.exec((err, stdout, stderr) => {
if (!err) {
console.log('gs executed w/o error');
console.log('stdout', stdout);
console.log('stderr', stderr);
resolve();
} else {
console.log('gs error:', err);
reject(err);
}
});
For more help, you can go through a sample repo that I created for this issue
https://github.com/krharsh17/ghostscript-firebase-sample

Overwrite Redis method

I try to add an option to my app to toggle using a cache. For cache I am using Redis and made simple wrapper for that. The problem is coming when I try to overwrite redis.get method, it's simply doens't work or cannot found this.
'use strict';
const redis = require('redis');
const config = require('../config');
const REDIS_EMPTY_VALUE = 'NOT_EXIST';
const MINUTE = 60;
let client = redis.createClient({
host: config.get('REDIS_HOST'),
port: config.get('REDIS_PORT')
});
client.on("error", function (err) {
logging.error('Redis Error: ' + err);
throw new Error(err);
});
/**
* Next are custom extensions for Redis module
*/
client.emptyValue = REDIS_EMPTY_VALUE;
client.minute = MINUTE;
client.setAndExprire = function(key, value, expire) {
this.set(key, value);
this.expire(key, expire);
};
// Here is the problem
client.get = function(key, cb) {
if (config.get('disable-cache') === 'true') return cb(null, null);
return client.get(key, cb);
}
module.exports = client;

Since you override client.get, the client.get become the new function that you defined. So that, you can call to the function that come along with redis package. You can use another object (custom) to call the redis function like below:
'use strict';
const redis = require('redis');
const config = require('../config');
const REDIS_EMPTY_VALUE = 'NOT_EXIST';
const MINUTE = 60;
const definedFunctions = [
'hgetall', 'hexists', 'hmset', 'hmget', 'hkeys', 'hvals', 'hget', 'hset', 'hdel',
'mget', 'mset', 'set', 'del', 'exists', 'lpush', 'lrange',
'zrange', 'zrem', 'zadd', 'zrangebyscore', 'zrevrangebyscore',
'expire', 'incrby'
];
let client = redis.createClient({
host: config.get('REDIS_HOST'),
port: config.get('REDIS_PORT')
});
client.on("error", function (err) {
console.error('Redis Error: ' + err);
throw new Error(err);
});
/**
* Next are custom extensions for Redis module
*/
const custom = {
emptyValue: REDIS_EMPTY_VALUE,
minute: MINUTE
};
definedFunctions.map((fn) => {
custom[fn] = (...args) => {
return client[fn](args);
};
});
custom.get = function(key, cb) {
if (config.get('disable-cache') === 'true') return cb(null, null);
return client.get(key, cb);
}
module.exports = custom;