From 9cbbebe7d6d9d042b06db734518209bd0531c407 Mon Sep 17 00:00:00 2001
From: Pavel Shevaev <pacha.shevaev@gmail.com>
Date: Wed, 26 Oct 2022 10:50:30 +0300
Subject: [PATCH] First commit

---
 go.mod      |  9 +++++++++
 go.sum      |  2 ++
 trc.go      | 42 ++++++++++++++++++++++++++++++++++++++++++
 trc_test.go | 15 +++++++++++++++
 4 files changed, 68 insertions(+)
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 trc.go
 create mode 100644 trc_test.go

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..82ca48b
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,9 @@
+module git.bit5.ru/backend/trc
+
+go 1.13
+
+require (
+	git.bit5.ru/backend/colog v1.0.0
+	git.bit5.ru/backend/errors v1.0.0
+	github.com/google/uuid v1.3.0
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..3dfe1c9
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,2 @@
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
diff --git a/trc.go b/trc.go
new file mode 100644
index 0000000..b878720
--- /dev/null
+++ b/trc.go
@@ -0,0 +1,42 @@
+package trc
+
+import (
+	"fmt"
+	"net/http"
+
+	"git.bit5.ru/backend/colog"
+	"git.bit5.ru/backend/errors"
+	"github.com/google/uuid"
+)
+
+type TraceId string
+
+func NewTraceId() TraceId {
+	return TraceId(uuid.New().String())
+}
+
+type SpanId string
+
+func NewSpanId() SpanId {
+	return SpanId(uuid.New().String())
+}
+
+//-----------------------------------------------------------------------------
+
+const TraceIdHeaderName = "trace-id"
+
+func RequestTraceId(req *http.Request) (TraceId, error) {
+	traceIdStr := req.Header.Get(TraceIdHeaderName)
+	if len(traceIdStr) == 0 {
+		return "", errors.New("Trace id must be specified.")
+	}
+
+	return TraceId(traceIdStr), nil
+}
+
+//-----------------------------------------------------------------------------
+
+func NewTraceLogger(logger *colog.CoLog, traceId TraceId) *colog.CoLog {
+	prefix := fmt.Sprintf("[trace_id:%s]", traceId)
+	return logger.Clone().AddPrefix(prefix)
+}
diff --git a/trc_test.go b/trc_test.go
new file mode 100644
index 0000000..68be879
--- /dev/null
+++ b/trc_test.go
@@ -0,0 +1,15 @@
+package trc_test
+
+import (
+	"testing"
+
+	"git.bit5.ru/backend/trc"
+)
+
+func TestNewTraceId(t *testing.T) {
+	traceId := trc.NewTraceId()
+
+	if len(traceId) == 0 {
+		t.Error("Empty traceId.")
+	}
+}