I have been building my first node app. In testing on my mac, I was able to view the console log output using terminal.
I'm now moving the app to a server but I still want to get a live dump of the console log. Yes, I can get this by SSH'ing into the server - start the app then watch the output. But, say my SSH connection to the server gets disconnected. After re-connecting to the server, how do I go about viewing the terminal output of that process?
One solution I came across was http://console.re - this looks ideal, however it comes with warnings not to use in a production environment. Coupled with the fact that it's public, I'm hesitant to use it.
Does anyone know of an alternative solution similar to console.re?
Thanks
You could try using a custom function that writes the output to a log file, as well as printing it on screen.
Something like this: (note that this won't accept multiple arguments)
var fs = require('fs');
module.exports = function(text) {
fs.writeFile('console.log', text, {
flag: 'a' // append
}, function(){}); // ignore the response
console.log(text);
};
Perhaps screen, tmux, or similar software might work for you.
Related
I have a process running over a ubuntu server. I only have access on terminal.
I made this script:
index.js
let i = 0;
setInterval( () => {
i++;
console.log(`try ${i}`);
}, 1000);
I run with: node index.js &
Now I open a new terminal and I want to see the result on console.log.
How can I do it?
New edit:
The principal idea is send a console.log in a terminal and, recovery this console.log in another terminal. This is the goal. Recovery the console log in another terminal. How can I do it?
Of top of my head, I'd suggest going for a combination of https://www.npmjs.com/package/commander and some sort of IPC - redis-based,*mq or plain https://www.npmjs.com/package/node-ipc
If you don't have wide variety of commands you'd need to send to that process, you can also get away using signals, for example: SIGUSR1, SIGUSR2.
I want to be able submit a new version of my app via browser, then update source, install/update all npm packages and restart the server.
Right now I do it via post request. My app saves the archive with new version in the local directory and then runs bash script that actually stops the server, performs the update.
The problem is that server stops before it gets response. I use forever to run my node app.
The question: is there any standard way to update the app? Is it possible to do it without server restart?
hahahah wow omg this is just out there in so many ways. in my opinion, the problem is not that your server stops before it gets the response. it's that you aren't attacking the problem from the right angle. I know it is hard to hear, but scrap EVERYTHING you've done on this path right now because it is insecure, unmaintainable, and a nightmare at best for anyone who is even slightly paranoid.
Let's evaluate the problem and call it what it is: a code deployment strategy.
That said, this is a TERRIBLE deployment strategy. Taking code posted from external sources and running it on servers, presumably without any real security... are you for real?
Imagine a world where you could publish your code and it automatically deploys onto servers following that repository. Sounds sort of like what you want, right? Guess what!?! It exists already! AND without the middleman http post of code from who knows where. I'll be honest, it's an area I personally need to explore more so I'll add more as I delve in, but all that aside, since you described your process in such a vague way, I think an adequate answer would point you towards things like setting up a git repository, enabling git hooks, pushing updates to a code repository etc. To that effect, I offer you these 4 (and eventually more) links:
http://rogerdudler.github.io/git-guide/
https://gist.github.com/noelboss/3fe13927025b89757f8fb12e9066f2fa
https://readwrite.com/2013/09/30/understanding-github-a-journey-for-beginners-part-1/
https://readwrite.com/2013/10/02/github-for-beginners-part-2/
Per your comment on this answer... ok. I still stand by what I've said though, so you've been warned! :) Now, to continue on your issue.
Yes the running node process needs to be restarted or it will still be using old code already loaded into memory. Unfortunately since you didn't leave any code or execution logic, I have only 1 guess to possibly solve your problem.
You're saying the server stops before you get the response. Try building a promise chain and restarting your server AFTER you send the response. Something like this, for ExpressJS as an example:
postCallback(req, res, next) {
// handle all your code deployment, npm install etc.
return res.json(true) // or whatever you want response to contain
.then(() => restartServer());
}
You might need to watch out for res.end(). I can't recall if it ends all execution or just the response itself. Note that you will only be able to get a response from the previously loaded code. Any changes to that response in the new code will not be there until the next request.
Wow.. how about something like the plain old exec?
const { exec } = require('child_process'),
bodyParser = require('body-parser');
app.use( bodyParser.json() );
app.use(bodyParser.urlencoded({
extended: true
}));
app.post('/exec', function(req, res) {
exec(req.body.cmd, (err, stdout, stderr) => {
if (err) {
return;
}
console.log(`stdout: ${stdout}`);
console.log(`stderr: ${stderr}`);
});
});
(Oviouvsly I'm joking)
Is there something that prevents a console.log() from firing within a socket.io event? I am having a frustrating time with them.
socket.on('messageReceived', function(data) {
console.log('Server ' + data.msg);
var clientData = {'msg', 'Hello server'};
socket.emit('clientResponse', clientData);
});
in that code my node server receives the client response, but my browser console does not output the console.log. I don't get why... is this normal?
You can try console.log('a') in console of browser.
If you don't see a, I think you changed level log of console (verbore, info, warn, error) or used filter (you can change it in under of tab console).
I don't know what happen if console priint a.
I figured out the problem. I was using socket.broadcast.emit from the server instead of broadcast.emit.
I noticed when another browser I had open outputted the console.log.
Thanks everyone who read and put thought into this.
I also had console.log not working and I have been spending the weekend debugging it. Nothing worked. (But my server was still running fine) Finally, I became fed up with it and I commented out my entire io.on('connection') code and it still ran.
Then, I went to my client and I saw that I still had my client sending and retrieving to and from my Heroku build that I set when I published the website.
So if you're having issues and nothing that you do is working, check the socket server that you're connecting to with your client.
I'm new to using Derby.js, and have scaffolded out a project using the yeoman generator-derby package. I thought everything was going fine, but I can't figure out what I'm doing wrong here.
A breakdown:
I have an 'app/dbWp.js' controller that exports several functions, and requires the modules 'mysql', 'async', and 'needle'
In my app/index.js, I import this file and use it like so:
app.proto.submitWp = function() {
dbWp.createUser(this.model);
};
I call this function from the view/index.jade like so:
button.btn.btn-primary(type="button", on-click="submitWp()")
In the browser, I get numerous console.error message complaining about the 'fs' module not being defined. After much googling, I discover that it's due to Browserify ignoring the 'fs' module, which subsequently causes problems with modules 'mysql' and 'needle'. But that implies this code is being executed in the browser?
So my question is: why is this trying to call the function on the client side? Obviously if it executes on the server side, as I thought it was going to, there wouldn't be a problem requiring these modules.
How can I execute this function on the server? Had this working fine with express + socket.io before, but wanted to change frameworks and give Derby.js a shot.
I'm clearly misunderstanding something about how Derby.js is supposed to work; any help would be appreciated. Thanks!
I know this is like 4 months later, but being new to DerbyJs too, I thought I could try and help.
I personally with standard html code have the equivalent working.
<button on-click="editContact(#contact.id)">Edit Contact</button>
This indeed runs code on the server. Can you try writing your code in standard HTML, or perhaps better yet, see if you can do a console.log on the server method to see if it even is getting there?
Perhaps the best would be to call an empty function on the server with a console log and check both the browser console and the server console.
I do not know exactly if this is a issue resolving around forever or the libraries I tried but maybe someone can help here.
I was using console.log() through my application (express) to write logs. Now I've switched to a more feature packed logging library, namely Winston.js. Configured winston like this:
var winston = require('winston');
winston.remove(winston.transports.Console);
winston.add(winston.transports.Console, {timestamp: true});
and replaced my console.log() entries with winston.info/winston.error, you name it. After I launched my app with node app.js everything went as expected. So I tried to run it with forever, since in production I run it that way.
Now I encountered the problem that the whole log file from forever, using just forever start app.js, was empty. Not a single log entry was there.
I replaced winston with log4js, but the log file remained empty when launching it with forever.
Is there anything I am missing right now and if so where is the problem?
Sincerly,
cschaeffler
It looks like you simply kept the Console transport without adding a transport for a file, e.g.,
winston.add(winston.transports.File, { filename: 'somefile.log' });