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-rw-r--r--vendor/github.com/go-logr/logr/slogr.go100
1 files changed, 100 insertions, 0 deletions
diff --git a/vendor/github.com/go-logr/logr/slogr.go b/vendor/github.com/go-logr/logr/slogr.go
new file mode 100644
index 000000000..28a83d024
--- /dev/null
+++ b/vendor/github.com/go-logr/logr/slogr.go
@@ -0,0 +1,100 @@
+//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
+}