Web Server Issues

[ishan0221]

Hi! So I was able to get up and running to the point of getting to the server. The gantry was able to home and center itself which was neat to see in action. When running:

npm run prod

the pi produced these errors:

events.js:291
[1] throw er; // Unhandled 'error' event
[1] ^
[1]
[1] Error [ERR_IPC_CHANNEL_CLOSED]: Channel closed
[1] at process.target.send (internal/child_process.js:708:16)
[1] at /home/pi/Sand-Table/Website/dist/routes/gcode_controller.js:310:31
[1] at sendNextCmd (/home/pi/Sand-Table/Website/dist/routes/gcode_controller.js:63:28)
[1] at ReadLineParser. (/home/pi/Sand-Table/Website/dist/routes/gcode_controller.js:70:30)
[1] at ReadLineParser.emit (events.js:314:20)
[1] at ReadLineParser.EventEmitter.emit (domain.js:486:12)
[1] at addChunk (_stream_readable.js:303:12)
[1] at readableAddChunk (_stream_readable.js:275:11)
[1] at ReadLineParser.Readable.push (_stream_readable.js:218:10)
[1] at ReadLineParser.Transform.push (_stream_transform.js:166:32)
[1] Emitted 'error' event on process instance at:
[1] at internal/child_process.js:712:35
[1] at processTicksAndRejections (internal/process/task_queues.js:75:11) {
[1] code: 'ERR_IPC_CHANNEL_CLOSED'
[1] }
[1] node dist/app.js exited with code 1

And I get a 502 bad gateway error when go to my pi's address.

[rdudhagra]

Hi Ishan,
Sorry for the late reply...to start, can you send me the output of node -v and npm -v? Also, what Raspberry Pi model are you running the webserver code on?

[ishan0221]

Hey! No worries, here are the outputs for package versions. Raspi is a 3b+. I've also tried to start from scratch (fresh OS) and I get the same output. Also just wanted say great job on the entire project. From documentation to support!! If its too big of an issue don't worry about it, I'm actually working on a simple python-flask app that takes in gcode.

pi@sandtable:~ $ node -v
v14.8.0
pi@sandtable:~ $ npm -v
7.8.0

[rdudhagra]

Odd. Ok, more questions:

1. Have you set up the systemctl stuff (make sand table start on boot)?
2. So follow-up to that question then: are you running two instances of the sand table website at the same time? (Run ps ax | grep node before running npm run prod and see if something sand table-related pops up.

It seems from your initial question that since the table homed itself, the website is actually running already, and you might be starting it again (so two concurrent instances). Try the above just to verify, and if you ever want to develop locally, you'll have to stop the sand table service:
sudo systemctl stop sandtable
and sudo systemctl disable sandtable to prevent it from launching on boot.

[ishan0221]

Apologies for the late reply but everything is now working!!! I ended solving the issue with a fresh SD and OS, followed the detailed steps and was able to launch the web server and start drawing. Glass tabletop is now on the way!! I also used the SKR mini MZ v1 board for simplicity and only $35 with the integrated tmc 2209 drivers for anyone else that is getting into this.

https://www.amazon.com/BIGTREETECH-Upgrade-Control-Controller-ANYCUBIC/dp/B08LD5Z66B/ref=sr_1_2?dchild=1&keywords=skr+mini+mz&qid=1620756968&sr=8-2

What a great project!!

[rdudhagra]

That’s great news! Glad that everything works in the end, and that table looks FANTASTIC by the way!