mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-11-27 14:16:39 +00:00
101 lines
3.6 KiB
Go
101 lines
3.6 KiB
Go
//go:build go1.21
|
|
// +build go1.21
|
|
|
|
/*
|
|
Copyright 2023 The logr Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package logr
|
|
|
|
import (
|
|
"context"
|
|
"log/slog"
|
|
)
|
|
|
|
// FromSlogHandler returns a Logger which writes to the slog.Handler.
|
|
//
|
|
// The logr verbosity level is mapped to slog levels such that V(0) becomes
|
|
// slog.LevelInfo and V(4) becomes slog.LevelDebug.
|
|
func FromSlogHandler(handler slog.Handler) Logger {
|
|
if handler, ok := handler.(*slogHandler); ok {
|
|
if handler.sink == nil {
|
|
return Discard()
|
|
}
|
|
return New(handler.sink).V(int(handler.levelBias))
|
|
}
|
|
return New(&slogSink{handler: handler})
|
|
}
|
|
|
|
// ToSlogHandler returns a slog.Handler which writes to the same sink as the Logger.
|
|
//
|
|
// The returned logger writes all records with level >= slog.LevelError as
|
|
// error log entries with LogSink.Error, regardless of the verbosity level of
|
|
// the Logger:
|
|
//
|
|
// logger := <some Logger with 0 as verbosity level>
|
|
// slog.New(ToSlogHandler(logger.V(10))).Error(...) -> logSink.Error(...)
|
|
//
|
|
// The level of all other records gets reduced by the verbosity
|
|
// level of the Logger and the result is negated. If it happens
|
|
// to be negative, then it gets replaced by zero because a LogSink
|
|
// is not expected to handled negative levels:
|
|
//
|
|
// slog.New(ToSlogHandler(logger)).Debug(...) -> logger.GetSink().Info(level=4, ...)
|
|
// slog.New(ToSlogHandler(logger)).Warning(...) -> logger.GetSink().Info(level=0, ...)
|
|
// slog.New(ToSlogHandler(logger)).Info(...) -> logger.GetSink().Info(level=0, ...)
|
|
// slog.New(ToSlogHandler(logger.V(4))).Info(...) -> logger.GetSink().Info(level=4, ...)
|
|
func ToSlogHandler(logger Logger) slog.Handler {
|
|
if sink, ok := logger.GetSink().(*slogSink); ok && logger.GetV() == 0 {
|
|
return sink.handler
|
|
}
|
|
|
|
handler := &slogHandler{sink: logger.GetSink(), levelBias: slog.Level(logger.GetV())}
|
|
if slogSink, ok := handler.sink.(SlogSink); ok {
|
|
handler.slogSink = slogSink
|
|
}
|
|
return handler
|
|
}
|
|
|
|
// SlogSink is an optional interface that a LogSink can implement to support
|
|
// logging through the slog.Logger or slog.Handler APIs better. It then should
|
|
// also support special slog values like slog.Group. When used as a
|
|
// slog.Handler, the advantages are:
|
|
//
|
|
// - stack unwinding gets avoided in favor of logging the pre-recorded PC,
|
|
// as intended by slog
|
|
// - proper grouping of key/value pairs via WithGroup
|
|
// - verbosity levels > slog.LevelInfo can be recorded
|
|
// - less overhead
|
|
//
|
|
// Both APIs (Logger and slog.Logger/Handler) then are supported equally
|
|
// well. Developers can pick whatever API suits them better and/or mix
|
|
// packages which use either API in the same binary with a common logging
|
|
// implementation.
|
|
//
|
|
// This interface is necessary because the type implementing the LogSink
|
|
// interface cannot also implement the slog.Handler interface due to the
|
|
// different prototype of the common Enabled method.
|
|
//
|
|
// An implementation could support both interfaces in two different types, but then
|
|
// additional interfaces would be needed to convert between those types in FromSlogHandler
|
|
// and ToSlogHandler.
|
|
type SlogSink interface {
|
|
LogSink
|
|
|
|
Handle(ctx context.Context, record slog.Record) error
|
|
WithAttrs(attrs []slog.Attr) SlogSink
|
|
WithGroup(name string) SlogSink
|
|
}
|