Open terminal from JavaScript and run bash command Linux - javascript

I am trying to run a bash file.
I can open the terminal and write bash run.sh and it works fine. But I am trying to do this via JavaScript. I am trying to open the terminal and run the command in that terminal.
let extExecCommand = `bash runtheme.sh`;
childProcess.spawnSync(extExecCommand, {shell: true});
Content of run.sh is this
#!/usr/bin/env bash
#This is a comment
#defining a variable
export FLASK_APP=script.py
export FLASK_DEBUG=1
flask run
xdg-open http://127.0.0.1:5000/
Actually, I want to run the flask app from a button click on the website.
Currently I am doing this, it will run the flask app but I can't kill the child process. I need to be able to run this app from a button click and need to be able to close it. As we can by pressing ctrl+c in a terminal window. So is there any way I can open the terminal window from JavaScript and run "bash run.sh" in that window?
I also tried making run.sh executable but it doesn't open the address in window automatically.

Javascript is client side, which means your code will only run on the clients browser sandbox. So for obvious security reasons you can't execute shell commands on the clients machine. You can run it from your own, local machine though. So here is my code if you want to do that:
const execSync = require('child_process').execSync;
const result = execSync('bash /path/to/executable.sh', {encoding: 'utf-8'});
console.log(result)
If you want to read more about sandboxes, i recommend this article which made things for me more clear: Sandboxes Explained

Related

Should I keep my prompt always open to run the scheduled node.js script?

In a previous question i asked about how to run index.js at an specific time, at first I thought all my project files would go to the web host, but i was told the index.js should be run on a server.
I googled and found it. i installed node-schedule, i wrapped my async puppeteer in a function then set schedule.scheduleJob( '44 02 * * *', myFunction) and put my index.html with js/css on a xampp and used ngrok. all right, im very happy my app is live.
now i need to know if i have to leave my prompt live so the scheduler will run always.
i mean, is there a better way to do it?
You have a few options:
systemd timers (.timer files), a modern version of cron / at
cron jobs (for repeated jobs)
at jobs (for once-off jobs)
screen. SSH into the host, run screen, run your command (node index.js), press Ctrl D to disconnect. You can then log out of the host and the command keeps running. Log back in and run screen -r to reconnect and see the output of the command.

How do I debug server and client simultaneously in WebStorm?

I have a node.js app that runs a server and sends index.html. The index.html interacts with the server.
I want to debug the complete app, but when I debug the app, WebStorm only debugs the server.
Is this even possible in WebStorm? If not, are there other tools that can do this?
In the Node.js run configuration, Browser/Live Edit tab, specify the URL of your server, tick both After launch and with JavaScript debugger checkboxes - client-side debugger will be launched once you start your node server with this configuration, so that you will be able to debug both simultaneously, using a single run configuration.
See also https://www.jetbrains.com/help/webstorm/debugging-javascript-in-chrome.html#debugging_js_on_external_web_server for some hints on debugging client-side code run in browser

Node JS ctrl + C doesn't stop server (after starting server with "npm start")

When I start my server with node app.js in the command line (using Git Bash), I can stop it using ctrl + C.
In my package.json file i got this start-script that allows me to use the command npm start to start the server:
"scripts": {
"start": "node app"
},
When I do this, the server starts as normal:
$ npm start
> nodekb#1.0.0 start C:\Projects\nodekb
> node app.js
Server started on port 3000...
But when i ctrl + C now, the server does not get stopped (the node process still remains in task manager). This means that I get an error when I try to do npm start again, because port 3000 is still being used.
I'm following a tutorial on youtube (video with timestamp), and when this guy ctrl + C and then runs npm start again, it works as normal.
Any ideas why my server process is not stopped when I use ctrl + C?
My app.js file if needed:
var express = require("express");
var path = require("path");
//Init app
var app = express();
//Load View Engine
app.set("views", path.join(__dirname, "views"));
app.set("view engine", "pug");
//Home Route
app.get("/", function(req, res) {
res.render("index", {
title: "Hello"
});
});
//Add route
app.get("/articles/add", function (req, res) {
res.render("add_article", {
title: "Add Article"
});
});
//Start server
app.listen(3000, function() {
console.log("Server started on port 3000...");
});
Thanks!
Ctrl + C does not kill the server. The resolution to the issue was using following code snippet in server.js:
process.on('SIGINT', function() {
console.log( "\nGracefully shutting down from SIGINT (Ctrl-C)" );
// some other closing procedures go here
process.exit(0);
});
This worked for me.
You can also check for other solutions mentioned at Graceful shutdown in NodeJS
I tried it on normal windows cmd, and it worked as it should there. Looks like it's a problem with git bash.
I encountered this problem in MSYS2 proper, even in latest build (x64 2018-05-31).
Luckily, Git for Windows maintain a customized MSYS2 runtime. They have patches that have not been sent upstream, including a patch that fixes emulation of SIGINT, SIGTERM and SIGKILL.
Discussion: https://github.com/nodejs/node/issues/16103
I was able to make my "MSYS2 proper" platform use Git for Windows' MSYS2 runtime, by following these instructions.
Repeated here for posterity:
Install inside MSYS2 proper
This guide assumes that you want the 64-bit version of Git for Windows.
Git for Windows being based on MSYS2, it's possible to install the git package into an existing MSYS2 installation. That means that if you are already using MSYS2 on your computer, you can use Git for Windows without running the full installer or using the portable version.
Note however that there are some caveats for going this way. Git for Windows created some patches for msys2-runtime that have not been sent upstream. (This had been planned, but it was determined in issue #284 that it would probably not be happening.) This means that you have to install Git for Windows customized msys2-runtime to have a fully working git inside MSYS2.
Here the steps to take:
Open an MSYS2 terminal.
Edit /etc/pacman.conf and just before [mingw32] (line #71 on my machine), add the git-for-windows packages repository:
[git-for-windows]
Server = https://wingit.blob.core.windows.net/x86-64
and optionally also the MINGW-only repository for the opposite architecture (i.e. MINGW32 for 64-bit SDK):
[git-for-windows-mingw32]
Server = https://wingit.blob.core.windows.net/i686
Authorize signing key (this step may have to be repeated occasionally until https://github.com/msys2/msys2/issues/62 is fixed)
curl -L https://raw.githubusercontent.com/git-for-windows/build-extra/master/git-for-windows-keyring/git-for-windows.gpg |
pacman-key --add - &&
pacman-key --lsign-key 1A9F3986
Then synchronize new repository
pacboy update
This updates msys2-runtime and therefore will ask you to close the window (not just exit the pacman process). Don't panic, simply close all currently open MSYS2 shells and MSYS2 programs. Once all are closed, start a new terminal again.
Then synchronize again (updating the non-core part of the packages):
pacboy update
And finally install the Git/cURL packages:
pacboy sync git:x git-doc-html:x git-doc-man:x git-extra: curl:x
Finally, check that everything went well by doing git --version in a MINGW64 shell and it should output something like git version 2.14.1.windows.1 (or newer).
Note: I found that the git-extra package installed by step 7 was quite intrusive (it adds a message "Welcome to the Git for Windows SDK!" to every terminal you open), so I removed it with pacman -R git-extra.
Note 2: I also found that Git for Windows' MSYS2 runtime opens in a different home directory than did MSYS2 proper's. This also means it reads in the wrong bash profile. I fixed this by adding an environment variable to Windows in the Control Panel: HOME=/C/msys64/home/myusername
I use git bash on my Windows machine and have run into this issue in the last month or so.
I still do not know what's causing it but I've found another way to stop it.
Open Task Manager
Go into the Processes tab
Look for node.exe and then press End Process
This has allowed me to stop the server quickly.
I had the same problem working with npm. But finally, I knew it was a problem with git itself.
There was a comment by dscho on GitHub 15 days ago. He said that they're working to fix this problem in the next release. He also shared the exact msys-2.0.dll file that can fix the problem for the people who can't wait.
Personally, I couldn't wait :p. So, I gave it a try, downloaded the file, and throw it in the git folder as he said. And the problem gone! It was awesome!
But please be sure to take a backup before you replace the file.
I also tried to kill it after running express as I used to; using taskkill /im node.exe on the cmd but there was no process to be found.
Check out this issue on GitHub,and search for the name of the file msys-2.0.dll to get to the comment faster.
Sometimes the node process hangs.
Check for the process ID using ps You may want to grep for node and then kill the process using kill -9 [PID]
Use Ctrl+\ to send the SIGQUIT signal. It will close the server.
Reference - https://en.wikipedia.org/wiki/Signal_(IPC)
I was able to fix this by switching to nodemon to run the server.
npm install --save-dev nodemon
package.json:
"scripts": {
"start": "nodemon app"
},
I was trying to get json-server to quit a custom server script, but it always left a child process running on Windows. It seems to be a specific problem running express via npm on Windows. If you run the server directly via the c:>node server.js then it seems to quit correctly.
I was able to debug this issue by checking the ports using TCP View, and realizing that my Node server was running even though I had pressed ctrl-C to stop it. I suggest killing the terminal you are running node from entirely.
Use Ctrl + C, then input: >pm2 stop all
This will stop all server or when you get stack with nodejs.
Inside package.json under scripts I had this line react-scripts start&. Notice it ends with an & which would send the process to the background and ctrl+c will not work. Somehow trying to bring this to the foreground with fg also did not work. Solved the problem by removing the &.
if you use Node.js Exec Extention to run your project from f8,
you can use also f9 to cancel running..
This is more than likely just a problem with your console not accurately sending the command to the process. This is pretty common, especially when using third party consoles like cmdr / conemu.
The solution?
Just hit ctrl+c several times until it closes :P

Node.JS: Why is my connection to localhost:3000 refused?

I'm a student going into back-end development for the first time and are trying to learn Node.JS. I downloaded a pdf book about Node.JS from sitepoint called: "Jumpstart Node.JS". In following the instructions to set up the server on the command line, install the dependencies, and navigate to localhost:3000, i got nothing except the following message: "Connection refused: localhost:3000", Can somebody please tell me what might have went wrong and how to fix it?
Edit1:
The instructions i followed is about setting up a node.js server using the Node command line, thus no code, simply cmd commands, however, here is a quick summary of the process i followed:
Created an account on MongoLabs and then a database using the free pricing plan.
Installed express using the command: npm install -g express#.2.5.8.
Created an applications with default options using this command: express authentication.
modified the package.json file in system32
installed the dependencies by typing cd authentication, hitting enter, and then typing the command: npm install
Typed node app and hit enter.
According to the instructions i should have seen a message: "Welcome to express" but instead got the error message.
In following the instructions to set up the server on the command line, install the dependencies, and navigate to localhost:3000
It seems that you didn't start the server.
Somewhere between installing the dependencies and navigating to the URL you need to actually start the server if you want it to serve the request.
Check that there is no copy of the server running in the background, or that another app is using the port currently.
(Your firewall show allow you to see which app has been allocated to that port)
Because nodejs requires it to be the only app on that port running on your computer.
Also try a different port maybe?

Can't get node-debug to work

This feels really silly, but I can't get node inspector / node-debug to work.
The instructions say to do npm install then to run node-debug web.js. So I did that. Now I have a lovely browser window open showing me my code with breakpoints... and no idea which url to use to actually access the code.
The inspector is at http://localhost:8080/debug?port=5858 and the terminal says:
> node-debug web.js
debugger listening on port 5858
Node Inspector is now available from http://localhost:8080/debug?port=5858
Debugging `web.js`
...
I've tried hitting up localhost:5000 (which is my express.js port) but that either fails if I don't have a separate node web.js instance running, or it succeeds if I have the other one running but doesn't trip any of the breakpoints in the inspector.
When I go to http://localhost:5858/, I get:
Remote debugging session already active
When I go to http://localhost:8080/, I get:
Cannot GET /
(the / path totally works on my server in general.)
By default node-debug starts app in --debug-brk mode.
This stops your app at first line (express not started).
You can use node-debug --no-debug-brk see the node-debug --h for more info.
Agh. Okay, looked at some more questions before I got this posted. Looks like the problem was just that I wasn't running the original instance in debug mode. Nobody had told me I had to, so I just didn't know otherwise!
What's working for me now:
> node debug web
then in a different terminal
> node-debug web.js

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