Detect windows and use non-colored stdout logs?

[karalabe]

I've just ran some code based on log15 under Windows and saw that the output is quite chaotic due to windows not recognizing the color defs and hence dumping a lot of extra characters all over the logs. At least this is my hunch, didn't really have time to track it down. Maybe you could add a build flag to disable colors if running on windows?

[inconshreveable]

Ouch, yeah, that's quite possible. What type of terminal were you using, cmd.exe or Powershell, or one of the other variants? For now, I'd suggest you do something like:

if runtime.GOOS == "windows" {
    log.Root().SetHandler(log.StreamHandler(os.Stdout, log.LogfmtFormat()))
}

[karalabe]

I usually use Linux, was just investigating a crash report in windows, so I've got nothing fancy installed, just cmd.exe.

I was also thinking about some similar solution, but since I'm using this in a library (https://github.com/project-iris/iris-go#logging) where anybody can override the default log settings, is there a way to "force" colorless logging even if the user changes some of the settings? (I'm not familiar with the log15 internals, hence my question :) ).

[inconshreveable]

You can force colorless logging with this code:

log.Root().SetHandler(log.StreamHandler(os.Stdout, log.LogfmtFormat()))

By default, when log15 init()'s, it checks if os.Stdout is a terminal, and if it is, uses log.TerminalFormat() which does the color formatting. Explicitly setting it to LogfmtFormat() or JsonFormat() will force no colorization.

[ChrisHines]

What about using the recently announced github.com/mattn/go-colorable package to get color for Windows too?

[inconshreveable]

thanks for pointing that out! i'm going to take a look at using mattn's package for this