[v2][WIP] Span hash sanitizer and enhance span hash adjuster

cmd/collector/app/sanitizer/hash_sanitizer.go

@@ -0,0 +1,39 @@
+// Copyright (c) 2022 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package sanitizer
+
+import (
+	"bytes"
+	"encoding/hex"
+
+	"github.com/jaegertracing/jaeger/model"
+)
+
+// NewHashingSanitizer creates a sanitizer to add hash field to spans
+func NewHashingSanitizer() SanitizeSpan {
+	return hashingSanitizer
+}
+
+func hashingSanitizer(span *model.Span) *model.Span {
+	// Check if hash already exists
+	for _, tag := range span.Tags {
+		if tag.Key == "span.hash" {
+			return span
+		}
+	}
+
+	buf := &bytes.Buffer{}
+	if err := span.Hash(buf); err != nil {
+		return span
+	}
+
+	hashStr := hex.EncodeToString(buf.Bytes())
+	span.Tags = append(span.Tags, model.KeyValue{
+		Key:   "span.hash",
+		VType: model.ValueType_STRING,
+		VStr:  hashStr,
+	})
+
+	return span
+}

cmd/collector/app/sanitizer/sanitizer.go

@@ -16,6 +16,7 @@ type SanitizeSpan func(span *model.Span) *model.Span
 func NewStandardSanitizers() []SanitizeSpan {
 	return []SanitizeSpan{
 		NewEmptyServiceNameSanitizer(),
+		NewHashingSanitizer(),
 	}
 }