Use a mature logging library

[KangLin]

The current logs do not meet the requirements. Continuing to reinvent the wheel is a waste of resources. It is recommended to use a mature logging library. For example:

• log4cplus
• logging-log4cxx

Although they are C++ libraries, they are easy to apply to this project. Only the macro needs to be rewritten TURN_LOG_FUNC

[jelmd]

IMHO not a good idea to pull in C++ things, unless they are completely standalone, i.e. do not require libstdc++, etc. Aren't there any pure C alternatives?

[KangLin]

They are completely standalone. I've only used these two C++ logging libraries. So let's discuss it here. - pure C: - log4c: But it doesn't seem to be maintained. - [zlog](https://github.com/HardySimpson/zlog) Everyone knows which logging libraries? At 2023-12-07 14:31:37, "Jens Elkner" ***@***.***> wrote: IMHO not a good idea to pull in C++ things, unless they are completely standalone, i.e. do not require libstdc++, etc. Aren't there any pure C alternatives? — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[jelmd]

They are completely standalone.

OK, just checked Ubuntu 20.04 because Ubuntu is IMHO a late adopter, i.e. if a certain package/version is there, probably all other distrOS have it, too.

• https://packages.ubuntu.com/focal/liblog4c3 depends on libexpat
• https://packages.ubuntu.com/focal/liblog4cplus-1.1-9 on libstdc++
• https://packages.ubuntu.com/focal/liblog4cxx10v5 on libstdc++ and libapr

In my java life I used log4j in 2000+ and later (~2006) slf4j + logback. Yes, great. But not sure, whether it is a little bit too much overhead. Anyway, whatever you choose, please make sure, that we can use the version/package the vendor ships for the related distros.

I've only used these two C++ logging libraries. So let's discuss it here. - pure C: - log4c: But it doesn't seem to be maintained.

I'm not coding in C++ at all, so can't really contribute much to this.

zlog

Never heard about it. Looks like that there is no vendor package for Ubuntu 20.04+.

Everyone knows which logging libraries?

[KangLin]

I looked at the source code, log4cplus provides a C interface 😄
https://github.com/log4cplus/log4cplus/blob/REL_1_1_2/include/log4cplus/clogger.h

logging-log4cxx does not provide a C interface 😢

In my java life I used log4j in 2000+ and later (~2006) slf4j + logback. Yes, great. But not sure, whether it is a little bit too much overhead. Anyway, whatever you choose, please make sure, that we can use the version/package the vendor ships for the related distros.

Stability and performance have been verified in practice.

[KangLin]

@coturn @eakraly @ggarber
TODO:

• Log interface

  • #define TURN_LOG_CATEGORY(category, level, ...)
    The newly added one can display logs by category
  • #define TURN_LOG_FUNC(level, ...)
    Stay compatible
  • void* turn_log_init();
  • void turn_log_clean(void*);
  • int turn_log_set_conf_file(const char* file);

• Log libraries

  • mature pure c log libraries. Please recommend the mature C logging library.
  • log4cplus

• The current log is frozen

[KangLin]

Use log4cplus #1351

[pwilczynskiclearcode]

Is there a way to set loglevel of coturn so it displays only warnings and errors? Current INFO-level is really verbose?
Or do we need to wait for the library change so it's possible?

[KangLin]

@pwilczynskiclearcode
The current log of coturn can set loglevel in command lien or configure file.
But the maintainability of the current logs is bad.

[KangLin]

@eakraly
In O&M, the function of output to the log server is very important too.
I've compared known C logging libraries and all of them are missing this feature.

[jelmd]

@pwilczynskiclearcode I've running an instance since mid of December: the main log contains 1-2K lines per week, only - and these are just the connection logs like 2024-01-17 23:25:55.610058 (18732): INFO: new session 000000000910 tid: 0 rsid: 1: local 123.45.67.89:443, remote 987.654.321.09:53562. I use the metric enhanced coturn (PR #1343) compiled with export TURN_NO_PQ=1 TURN_NO_MYSQL=1 TURN_NO_MONGO=1 TURN_NO_HIREDIS=1 (because no-one needs it on our site). It has connection logging turned off by default (and thus is almost a no-op log), but allows one to enable it by ip-log option. FWIW: my related settings are:

# Verbose Mode: verbose .. moderate verbose, Verbose .. extra verbose
#verbose
# enable prometheus metrics
prom
prom-compact
prom-sid
prom-sid-retain = 30
log-ip
# Log to a single filename (rather than new log files each startup).
log-file=/var/log/coturn.log
simple-log
new-log-timestamp
new-log-timestamp-format="%F %T.%N"