App running in background, reliably and debuggable

[scripting]

I am working on a Node app that must:

1. run in the background,

2. disconnected from the terminal,

3. survives the terminal window being closed,

4. yet is easy to quit so I can run a new version.

The product will remain in active development at the same time it is deployed, for the foreseeable future.

It's running on Ubuntu 18.04.3 (LTS) x64 on digitalocean.com.

I am currently using nohup node appname.js & to launch the app, and killAll node, to terminate it, and the apps it launches.

This method seems pretty good. I am able to Control-C after launching the app and it keeps running in the background. It seems to survive closing the terminal and logging on again.

Curious to know what other devs think? What method do you use to launch and kill an app in the background when you're actively developing it?

[easp]

Sounds like you are running on a unix variant. Which one? They have different canonical ways to manage background daemons/servers.

Also, what, if any, front-end web server are you using?

[scripting]

Ooops. I should have said -- Ubuntu.

[toontoet]

Have a look at what pm2 has to offer. It allows you to manage node processes and more: https://pm2.keymetrics.io/

It also has a nice develop feature so it restarts an app when source code changes. And nice features to deploy code to remote servers.

[scripting]

I need something much much lighter weight.

[mterenzio]

Will forever keep it running in the background?

Then forever list

And forever stop [pid]

[scripting]

Matt. this app is forever.

[tedchoward]

I’ve been using pm2 on my server to run river5 for quite a while. It keeps it going, survives restarts, etc. I haven’t thought a lot about it, I just set it up once a long time ago, and then forgot about it.

[danmactough]

I am currently using nohup node appname.js & to launch the app, and killAll node, to terminate it, and the apps it launches.

With your requirements, this is what I would do. (Actually, I run everything inside Docker containers, now. But before I started doing that, this is what I would have done.)

[easp]

I'd use "systemd" to manage the node process. That way it gets started when/if the machine reboots. It can also automatically restart the process after a crash. Systemd is already installed on ubuntu and is responsible for managing pretty much every persistent process and subsystem, so you won't have to worry about installing extra software.

This article looks like a decent overview of configuring a systemd managed node app. All it takes a 10-15 line config file.

[scripting]

Thanks @easp -- I'll look into it. I see it does allow for the possibility of quitting and relaunching, so it may be usable for a project under development like this one.