F#ing Simple Logger

An rich, simple, and efficient purely functional micro logging library for F#.

This isn't frequently updated because it's literally perfect (well, probably, almost).

This is used in several production systems. It's great. It's perfect, and you should use it!

Is this any good?

Yes and you should use it.

Installation

You can install it via NuGet. You should already know how to do that. This runs on .NET Core, 6.0, 7.0, etc. Go forth and use it.

HOW TO LOG STUFF:

let smartDevCount = 5
let devCount = 5

open FSLogger
let log = Logger.ColorConsole
log.I "Uzing da librariez" // log to info
log.Wf "%d out of %d devz recommend FsLogger" 5 5 // log to warning with format features

let descr = "best"
log.N $"This is the ${descr} library" // log to notice using 5.0-style interpolation

Is that it?

Okay fine. The library can do a bunch of stuff.

Also has some nice colour output by default.

More examples

Setting a path to log stuff to:

open FSLogger

let log = 
    Logger.ColorConsole
    |> Logger.withPath "MyApp"

module SeriousBusiness = 
    let doStuff (log: Logger) (aNumber: int) =
        // shadow with a better path
        let log =  log |> Logger.appendPath "doStuff"
        if aNumber > 5 then
            log.W $"Oh no, {aNumber} is bigger than 5!"
            // do something important
	    ignore aNumber

Adding a custom consumer:

let enterpriseConsumer (l:LogEntry) = 
	match l.Level with
	| LogLevel.Warn -> callManagement(l.Message)
	| LogLevel.Error -> blameAnotherDeveloper(l.Message)
	| LogLevel.Fatal -> submitNewJobApplication()
	| _ -> () // ignore the rest

let log = 
	Logger.Console
	|> Logger.addConsumer enterpriseConsumer

I want more examples!

Read the source code! It's super simple and documented.