Move tracing to pkg/tracing

Signed-off-by: Derek McGowan <derek@mcg.dev>

pkg/tracing/log.go

@@ -0,0 +1,66 @@
+/*
+   Copyright The containerd 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 tracing
+
+import (
+	"github.com/sirupsen/logrus"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// NewLogrusHook creates a new logrus hook
+func NewLogrusHook() *LogrusHook {
+	return &LogrusHook{}
+}
+
+// LogrusHook is a logrus hook which adds logrus events to active spans.
+// If the span is not recording or the span context is invalid, the hook is a no-op.
+type LogrusHook struct{}
+
+// Levels returns the logrus levels that this hook is interested in.
+func (h *LogrusHook) Levels() []logrus.Level {
+	return logrus.AllLevels
+}
+
+// Fire is called when a log event occurs.
+func (h *LogrusHook) Fire(entry *logrus.Entry) error {
+	span := trace.SpanFromContext(entry.Context)
+	if span == nil {
+		return nil
+	}
+
+	if !span.SpanContext().IsValid() || !span.IsRecording() {
+		return nil
+	}
+
+	span.AddEvent(
+		entry.Message,
+		trace.WithAttributes(logrusDataToAttrs(entry.Data)...),
+		trace.WithAttributes(attribute.String("level", entry.Level.String())),
+		trace.WithTimestamp(entry.Time),
+	)
+
+	return nil
+}
+
+func logrusDataToAttrs(data logrus.Fields) []attribute.KeyValue {
+	attrs := make([]attribute.KeyValue, 0, len(data))
+	for k, v := range data {
+		attrs = append(attrs, any(k, v))
+	}
+	return attrs
+}