custom slog Handler which adds Attribute and WithGroup

[Johann Höchtl]

I created a custom slog Handler which adds an attribute eventId which is a GUID

A NewLogger function returns that logger wrapped into a group: Every further key-value provided should go into that group.

Unfortunately the eventId also gets promoted into that group although it should be at the parent level.

See here the Goplay https://play.golang.com/p/a10f09jMwL3

Thank you for your help, Johann

[Johann Höchtl]

As I got zero reply to that answer, let me rephrase it probably more easily:

I would like to use slog, no other logging library

I would like to have an entry called eventID which is at the root level and has a unique uuid for every log entry

I would like to use a group for every application specific key-val pairs

What I trired so far:

• Use a Handler to add eventID : The key gets added to the logger yet at the group nesting level, not at the root level
• Use a ReplaceAttr-Function: I add the key on initiailisation yet leave the value unassigned to Replace it in the ReplaceAttr-Function: The ReplaceAttr-Function sees the  root level addded eventID only untill a call to .WithGroup, then the  eventId is no longer available within the ReplaceAttr-Function

Any help?

[Sean Liao]

The slog API doesn't allow wrapping handlers this way. slog.Handlers hold state for the current open group.

You'll need a full implementation of a handler to do this.

(Technically it's possible if you record the group/attrs in With/WithGroup yourself and only call the wrapped handler in Handle, but you lose any preformatting performance benefits a handler may have implemented.)

- sean

--
You received this message because you are subscribed to the Google Groups "golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/16dc9f51-6c8c-4fd9-9942-5e365399e26dn%40googlegroups.com.