feat: added --follow option to hyprctl rollinglog #6300

[Truenya]

Describe your PR, what does it fix/add?

Added --follow option to hyprctl rollinglog
#6300

Is there anything you want to mention? (unchecked code, possible bugs, found problems, breaking compatibility, etc.)

Also added onlybuild command to Makefile (it is annoying to completely rebuild whole project any time).

Is it ready for merging, or does it need work?

Ready, working, tested.

[vaxerski]

tbh I fail to see the use - one can always like... watch?

Maybe rollinglog should just do that?

[zjeffer]

Using watch is kind of annoying and very limiting: hyprctl rollinglog only shows you the last 50 lines, so using watch (with for example -n 0.1 to make sure you get every line) will keep showing the last 50 lines meaning you can't scroll up. I sometimes want to know what happened in the last 100 lines, for example, so I need the ability to scroll up in the logs.

I'll test this PR tomorrow, but from the description it does exactly what I wanted.

[Truenya]

https://www.youtube.com/watch?v=JIz6l6Xlouc

[Truenya]

@vaxerski can i ask for a review?

[rtgiskard]

As rollinglog can not follow the output like jounalctl -f does, I'm generally using tail -f /run/user/1000/hypr/*/hyprland.log instead.

It would be good if rollinglog can follow the log, but I don't really like current implemention with keep sending log via the socket in a thread, I'd prefer a wrapper for tail which would be simple and efficient enough.

And, perhaps, use something like spdlog, and/or with syslog as backend, then just use journalctl to manage the logs.

[Truenya]

I'd prefer a wrapper for tail which would be simple and efficient enough

Small detail: rollinglog works independently from any other logging methods. So we cannot use tail wrapper here. If the user does not want to write the log to a file, we cannot force him.

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PS
I was also confused that I had to use features that are not used in the project(multithreading), but I did not find any other ways to provide the required functionality. I would be grateful for any hint

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PSS
If we can get past the idea that there can be multiple followers, we can also use Linux FIFO, but it's basically like sockets and can't make the code more efficient. I will say more, this will slow down the execution compared to writing to the map under a lock.

[zjeffer]

rollinglog works independently from any other logging methods

What do you mean with this?

When I initially created the issue, my request was basically to make hyprctl rollinglog -f be a wrapper around tail -f <logfile>, without having to specify the whole path to the logfile.

If we can get past the idea that there can be multiple followers, we can also use Linux FIFO, but it's basically like sockets and can't make the code more efficient. I will say more, this will slow down the execution compared to writing to the map under a lock.

This seems to be adding lots of complexity for something that could just be a wrapper for tail, like @rtgiskard says...

[Truenya]

@zjeffer You can disable logging in the configuration and still get it with the rollinglog command. The added --follow option preserves this logic.

[vaxerski]

additionally:

• clang-format needed
• no {} around short ifs (too many cases to label all)
• wiki mr needed

[Truenya]

• wiki mr needed

can u please explain more concrete? what exactly needs to be described?
Is this enough? hyprwm/hyprland-wiki#675

[Truenya]

no {} around short ifs (too many cases to label all)

do you mean that it is necessary to remove {} for short Ifs? as far as I can see they are everywhere in MR

[vaxerski]

the wiki mr yea thats all, just to let people know

for ifs:

we always

if (a) 
   b();

in hyprland

[Truenya]

the wiki mr yea thats all, just to let people know

for ifs:

we always

if (a) 
   b();

in hyprland

Done

[vaxerski]

this MR will clash with #6380 and since that one is smaller can you please wait for until it's merged and then just fixup this one (use log instead of std::cout for ignorable logs)

[vaxerski]

6380 is merged, can you please update the MR?

[Truenya]

@vaxerski done

[vaxerski]

conflict

[Truenya]

@vaxerski resolved

[vaxerski]

yabba dabba doo