问题
How can I achieve MDC Logging (Java) in GoLang?
I need to add UUIDs in all server logs in order to be able to trace concurrent requests.
回答1:
Java MDC relies on thread local storage, something Go does not have.
The closest thing is to thread a Context through your stack.
This is what more and more libraries are doing in Go.
A somewhat typical way is to do this via a middleware package that adds a request id to the context of a web request, like:
req = req.WithContext(context.WithValue(req.Context(),"requestId",ID))
Then, assuming you pass the context around, you pull it out with ctx.Value("requestId") and use it wherever it makes sense.
Possibly making your own custom logger function like:
func logStuff(ctx context.Context, msg string) {
log.Println(ctx.Value("requestId"),msg) // call stdlib logger
}
There's a bunch of ways you may want to handle this, but that's a fairly simple form.
来源：https://stackoverflow.com/questions/41048757/golang-logging-with-mapped-diagnostic-context