For some reason I often notice after having my terminal open for a while, I can't see the output from my nodejs server anymore. I know it's running, though. How do I re-open the node output info? (By output info, I mean "console.log" in nodejs code. I'm running on linux.
For anyone looking for an answer to this, my research conclusion is that it's an artifact of nodemon that exists. You have to physically go into the port and kill it, which I've spent an enormous amount of time doing. Not very helpful if you were running this in production and you couldn't see output anymore. But it is what it is.
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I don't have Sudo access, so currently i can't install 'Forever' https://www.npmjs.com/package/forever
Instead i am simply using 'Screen'.
I am running a node.js server, at a random point, the node server stops, and screen exits. I cannot seem to collect any error data on this. I seem to be completely unaware of why its happening and cannot think of a way to catch what is happening. It doesn't happen often (maybe 1 time per day). When i load putty back up and login to my Apache server through terminal, i type screen -x or screen -r and it tells me there are no screens attached. The node server process definitely stops because the app it runs stops working.
Obviously i can't post all the code here, there is tons of it. But everything appears to work wonderfully, except every now and then, something goes wrong and it closes the attached screen.
If there was a problem with the node server, i would expect a crash, and the attached screen would stay attached. There would be an error outputted to the terminal for me to see when i open it. But in this case, it totally closes the attached screen.
Does anybody know what kind of error can cause this?
On a side note, is there an alternative to 'Forever' that can be installed without Sudo access?
My node version wasn't correct which is why Forever wasn't installing. I didn't need SUDO after all. I am now using Forever and hopefully this will shed light on what is going on as i have a out.log file which should catch whatever the problem is. :-)
I am running some application in NodeJS that retrieves data from a database and serve at port 3000.
It is running fine most of the time but sometimes it just errors out (it could be too many connections or network issue or some sql injection etc.). This happens every 2-3 days randomly.
While I am figuring out root cause - what is the best way to have NodeJS always 'ON' - meaning if it stops running - some process kicks it and it starts again?
You can use forever as stated by the previous answer, but as I've worked with forever before, I'd suggest using the pm2 process manager. It has, on top of what you need, some more advanced functionalities and is well-documented.
Try this:
forever start -w <filename>
-w is for watch. it watches the file changes and restarts if any changes found.
Also, if the script is unexpectedly stopped, it will try to restart it.
forever list for details of the process.
you will see the PID, filename, log filename.
in the log file, you can see the log of your script.
Hope it helps. :)
I'm using node v6.10.0 and trying to figure out why my --debug-brk is so incredibly slow. Without this flag (with just --inspect or --debug), it's almost instantaneous, though the debugger still takes forever to attach.
This one flag dramatically increases the load time. My project is taking 50s+ to start up when debugging is enabled.
Any ideas on how to start debugging this issue?
Edit: To be clear, it's happening across two computers and does NOT happen with Hello World.
Edit 2: More detail. I'm using es6. I used webstorm to log out what was going on and found that it was just taking forever to read all my modules? Perhaps that's what's going on?
Is there a way to speed this up? It's taking 34 seconds just to load all the require statements.
Edit 3: It's absolutely the files and require statements. I moved some of the require statements to only load after the database connection is established. The connection is established instantly, but the process hangs on moving forward after that (again for several, several seconds).
Is there any way to speed this up?
What do you mean by "load time"? Are you talking about time between opening the frontend (e.g. Chrome DevTools) and hitting the breakpoint on the first line of your script?
From your description it sounds like there's an issue with the socket connection being slow. Some things to check:
If the URL your Node.js version outputs has localhost - replace it with 127.0.0.1. Some OSes use DNS to resolve this name and might fail to resolve it or to be slow.
Do you have any issues with the network access? Particular Chrome DevTools version has to be downloaded for your node version, this might be slow.
This might be a bug in particular Node.js version (I cannot recall anything specific that might've caused this). What is puzzling is that it is app specific - when you run with --debug-brk or --inspect-brk no JS is executed until after the debug frontend is connected.
Please consider reporting this issue on Node.js bugtracker - feel free to CC me directly (add #eugeneo anywhere in the bug description)... Is there any chance I could see your code - e.g. is it on GitHub? Also - can you please try a newer Node version?
I have looked for answer for this question and have to find anything quiet like what I experience!
I set up an Ubuntu instance on AWS, standard configurations, medium tier.
I ssh into the server, and then I have a script running in Node, which I launch with sudo nodejs server.js .
When it runs, it has a few REST endpoints which work just fine, and those write to a mongodb (which, also works just fine). However, if I leave my computer and come back the next day, I get the standard SSH broken pipe, which is fine. But! When I try to use my REST api at that point, the node server.js is clearly not running.
I am the only person consuming this api, so I don't think errors are bringing it down.
Has anyone experience anything like this? Perhaps there is a configuration I am missing?
A friend just answered it for me,
sudo nodejs server.js & > mylog.out
This makes it run in the background and print the stdout to a log instead of nowhere (nowhere due to broken pipe)
We have a whiteboard application powered by NodeJS sitting on a 'cloud' server (rackspace cloud). I recently scaled our server up to accommodate for the anticipated traffic with our launch, and in the process it shut down NodeJS. We are launching our product in a few hours, and our NodeJS developer has gone for the day.
The whiteboard application is supposed to run at http://rayku.com:8001 (the port is opened). However, it's not working because the port isn't listening to anything with NodeJS shut down.
I honestly have no idea which js file to run in order to start NodeJS for the whiteboard. There are many js files in a 'whiteboard' folder. Do you know what type of code I should look for that might suggest it is the right one? Or, do you know what types of logs I can dig up that might point me in the right direction?
Much appreciated
Look for app.js, server.js or something similar. It isn't required but a lot of people use app.js from what I have seen.
node or nodejs is typically the command to start. You may need to set environmental variables or arguments depending on how the developer set things up.
Also make sure to run it with screen or forever so it doesn't quit when you log out.
For common code. createServer is probably what is used to open the server itself. That is consistent between the core libraries and a lot of the frameworks. There might be another file that loads the module prior to executing so running might not work.