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-rw-r--r--vendor/github.com/go-logr/logr/sloghandler.go192
1 files changed, 192 insertions, 0 deletions
diff --git a/vendor/github.com/go-logr/logr/sloghandler.go b/vendor/github.com/go-logr/logr/sloghandler.go
new file mode 100644
index 000000000..82d1ba494
--- /dev/null
+++ b/vendor/github.com/go-logr/logr/sloghandler.go
@@ -0,0 +1,192 @@
+//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"
+)
+
+type slogHandler struct {
+ // May be nil, in which case all logs get discarded.
+ sink LogSink
+ // Non-nil if sink is non-nil and implements SlogSink.
+ slogSink SlogSink
+
+ // groupPrefix collects values from WithGroup calls. It gets added as
+ // prefix to value keys when handling a log record.
+ groupPrefix string
+
+ // levelBias can be set when constructing the handler to influence the
+ // slog.Level of log records. A positive levelBias reduces the
+ // slog.Level value. slog has no API to influence this value after the
+ // handler got created, so it can only be set indirectly through
+ // Logger.V.
+ levelBias slog.Level
+}
+
+var _ slog.Handler = &slogHandler{}
+
+// groupSeparator is used to concatenate WithGroup names and attribute keys.
+const groupSeparator = "."
+
+// GetLevel is used for black box unit testing.
+func (l *slogHandler) GetLevel() slog.Level {
+ return l.levelBias
+}
+
+func (l *slogHandler) Enabled(_ context.Context, level slog.Level) bool {
+ return l.sink != nil && (level >= slog.LevelError || l.sink.Enabled(l.levelFromSlog(level)))
+}
+
+func (l *slogHandler) Handle(ctx context.Context, record slog.Record) error {
+ if l.slogSink != nil {
+ // Only adjust verbosity level of log entries < slog.LevelError.
+ if record.Level < slog.LevelError {
+ record.Level -= l.levelBias
+ }
+ return l.slogSink.Handle(ctx, record)
+ }
+
+ // No need to check for nil sink here because Handle will only be called
+ // when Enabled returned true.
+
+ kvList := make([]any, 0, 2*record.NumAttrs())
+ record.Attrs(func(attr slog.Attr) bool {
+ kvList = attrToKVs(attr, l.groupPrefix, kvList)
+ return true
+ })
+ if record.Level >= slog.LevelError {
+ l.sinkWithCallDepth().Error(nil, record.Message, kvList...)
+ } else {
+ level := l.levelFromSlog(record.Level)
+ l.sinkWithCallDepth().Info(level, record.Message, kvList...)
+ }
+ return nil
+}
+
+// sinkWithCallDepth adjusts the stack unwinding so that when Error or Info
+// are called by Handle, code in slog gets skipped.
+//
+// This offset currently (Go 1.21.0) works for calls through
+// slog.New(ToSlogHandler(...)). There's no guarantee that the call
+// chain won't change. Wrapping the handler will also break unwinding. It's
+// still better than not adjusting at all....
+//
+// This cannot be done when constructing the handler because FromSlogHandler needs
+// access to the original sink without this adjustment. A second copy would
+// work, but then WithAttrs would have to be called for both of them.
+func (l *slogHandler) sinkWithCallDepth() LogSink {
+ if sink, ok := l.sink.(CallDepthLogSink); ok {
+ return sink.WithCallDepth(2)
+ }
+ return l.sink
+}
+
+func (l *slogHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
+ if l.sink == nil || len(attrs) == 0 {
+ return l
+ }
+
+ clone := *l
+ if l.slogSink != nil {
+ clone.slogSink = l.slogSink.WithAttrs(attrs)
+ clone.sink = clone.slogSink
+ } else {
+ kvList := make([]any, 0, 2*len(attrs))
+ for _, attr := range attrs {
+ kvList = attrToKVs(attr, l.groupPrefix, kvList)
+ }
+ clone.sink = l.sink.WithValues(kvList...)
+ }
+ return &clone
+}
+
+func (l *slogHandler) WithGroup(name string) slog.Handler {
+ if l.sink == nil {
+ return l
+ }
+ if name == "" {
+ // slog says to inline empty groups
+ return l
+ }
+ clone := *l
+ if l.slogSink != nil {
+ clone.slogSink = l.slogSink.WithGroup(name)
+ clone.sink = clone.slogSink
+ } else {
+ clone.groupPrefix = addPrefix(clone.groupPrefix, name)
+ }
+ return &clone
+}
+
+// attrToKVs appends a slog.Attr to a logr-style kvList. It handle slog Groups
+// and other details of slog.
+func attrToKVs(attr slog.Attr, groupPrefix string, kvList []any) []any {
+ attrVal := attr.Value.Resolve()
+ if attrVal.Kind() == slog.KindGroup {
+ groupVal := attrVal.Group()
+ grpKVs := make([]any, 0, 2*len(groupVal))
+ prefix := groupPrefix
+ if attr.Key != "" {
+ prefix = addPrefix(groupPrefix, attr.Key)
+ }
+ for _, attr := range groupVal {
+ grpKVs = attrToKVs(attr, prefix, grpKVs)
+ }
+ kvList = append(kvList, grpKVs...)
+ } else if attr.Key != "" {
+ kvList = append(kvList, addPrefix(groupPrefix, attr.Key), attrVal.Any())
+ }
+
+ return kvList
+}
+
+func addPrefix(prefix, name string) string {
+ if prefix == "" {
+ return name
+ }
+ if name == "" {
+ return prefix
+ }
+ return prefix + groupSeparator + name
+}
+
+// levelFromSlog adjusts the level by the logger's verbosity and negates it.
+// It ensures that the result is >= 0. This is necessary because the result is
+// passed to a LogSink and that API did not historically document whether
+// levels could be negative or what that meant.
+//
+// Some example usage:
+//
+// logrV0 := getMyLogger()
+// logrV2 := logrV0.V(2)
+// slogV2 := slog.New(logr.ToSlogHandler(logrV2))
+// slogV2.Debug("msg") // =~ logrV2.V(4) =~ logrV0.V(6)
+// slogV2.Info("msg") // =~ logrV2.V(0) =~ logrV0.V(2)
+// slogv2.Warn("msg") // =~ logrV2.V(-4) =~ logrV0.V(0)
+func (l *slogHandler) levelFromSlog(level slog.Level) int {
+ result := -level
+ result += l.levelBias // in case the original Logger had a V level
+ if result < 0 {
+ result = 0 // because LogSink doesn't expect negative V levels
+ }
+ return int(result)
+}