From 4892335cca72e213fc19d7c189685635c7e76723 Mon Sep 17 00:00:00 2001
From: Samuel Berthe <dev@samuel-berthe.fr>
Date: Mon, 30 Oct 2023 10:39:51 +0100
Subject: [PATCH] feat: adding otel

---
 README.md     | 15 +++++++++++++++
 go.mod        |  2 ++
 go.sum        |  4 ++++
 middleware.go | 17 +++++++++++++++++
 4 files changed, 38 insertions(+)

diff --git a/README.md b/README.md
index 91628bd..8175034 100644
--- a/README.md
+++ b/README.md
@@ -96,6 +96,21 @@ e.Logger.Fatal(e.Start(":4242"))
 // time=2023-04-10T14:00:00Z level=INFO msg="Success"  status=200 method=GET path=/ route=/ ip=::1 latency=25.958µs user-agent=curl/7.77.0 time=2023-04-10T14:00:00Z request-id=229c7fc8-64f5-4467-bc4a-940700503b0d
 ```
 
+### OTEL
+
+```go
+logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
+
+config := sloggin.Config{
+	WithSpanID:  true,
+	WithTraceID: true,
+}
+
+e := echo.New()
+e.Use(slogecho.NewWithConfig(logger, config))
+e.Use(middleware.Recover())
+```
+
 ### Verbose
 
 ```go
diff --git a/go.mod b/go.mod
index ba68c0b..f96e899 100644
--- a/go.mod
+++ b/go.mod
@@ -14,6 +14,8 @@ require (
 	github.com/mattn/go-isatty v0.0.19 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/valyala/fasttemplate v1.2.2 // indirect
+	go.opentelemetry.io/otel v1.19.0 // indirect
+	go.opentelemetry.io/otel/trace v1.19.0 // indirect
 	golang.org/x/crypto v0.14.0 // indirect
 	golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 // indirect
 	golang.org/x/net v0.17.0 // indirect
diff --git a/go.sum b/go.sum
index ebfb2c5..f1667a2 100644
--- a/go.sum
+++ b/go.sum
@@ -27,6 +27,10 @@ github.com/valyala/bytebufferpool v1.0.0/go.mod h1:6bBcMArwyJ5K/AmCkWv1jt77kVWyC
 github.com/valyala/fasttemplate v1.2.1/go.mod h1:KHLXt3tVN2HBp8eijSv/kGJopbvo7S+qRAEEKiv+SiQ=
 github.com/valyala/fasttemplate v1.2.2 h1:lxLXG0uE3Qnshl9QyaK6XJxMXlQZELvChBOCmQD0Loo=
 github.com/valyala/fasttemplate v1.2.2/go.mod h1:KHLXt3tVN2HBp8eijSv/kGJopbvo7S+qRAEEKiv+SiQ=
+go.opentelemetry.io/otel v1.19.0 h1:MuS/TNf4/j4IXsZuJegVzI1cwut7Qc00344rgH7p8bs=
+go.opentelemetry.io/otel v1.19.0/go.mod h1:i0QyjOq3UPoTzff0PJB2N66fb4S0+rSbSB15/oyH9fY=
+go.opentelemetry.io/otel/trace v1.19.0 h1:DFVQmlVbfVeOuBRrwdtaehRrWiL1JoVs9CPIQ1Dzxpg=
+go.opentelemetry.io/otel/trace v1.19.0/go.mod h1:mfaSyvGyEJEI0nyV2I4qhNQnbBOUUmYZpYojqMnX2vo=
 golang.org/x/crypto v0.14.0 h1:wBqGXzWJW6m1XrIKlAH0Hs1JJ7+9KBwnIO8v66Q9cHc=
 golang.org/x/crypto v0.14.0/go.mod h1:MVFd36DqK4CsrnJYDkBA3VC4m2GkXAM0PvzMCn4JQf4=
 golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 h1:k/i9J1pBpvlfR+9QsetwPyERsqu1GIbi967PQMq3Ivc=
diff --git a/middleware.go b/middleware.go
index 106f10a..cd317b2 100644
--- a/middleware.go
+++ b/middleware.go
@@ -12,6 +12,7 @@ import (
 
 	"github.com/labstack/echo/v4"
 	"github.com/samber/lo"
+	"go.opentelemetry.io/otel/trace"
 )
 
 const (
@@ -45,6 +46,8 @@ type Config struct {
 	WithRequestHeader  bool
 	WithResponseBody   bool
 	WithResponseHeader bool
+	WithSpanID         bool
+	WithTraceID        bool
 
 	Filters []Filter
 }
@@ -64,6 +67,8 @@ func New(logger *slog.Logger) echo.MiddlewareFunc {
 		WithRequestHeader:  false,
 		WithResponseBody:   false,
 		WithResponseHeader: false,
+		WithSpanID:         false,
+		WithTraceID:        false,
 
 		Filters: []Filter{},
 	})
@@ -84,6 +89,8 @@ func NewWithFilters(logger *slog.Logger, filters ...Filter) echo.MiddlewareFunc
 		WithRequestHeader:  false,
 		WithResponseBody:   false,
 		WithResponseHeader: false,
+		WithSpanID:         false,
+		WithTraceID:        false,
 
 		Filters: filters,
 	})
@@ -169,6 +176,16 @@ func NewWithConfig(logger *slog.Logger, config Config) echo.MiddlewareFunc {
 				}
 			}
 
+			// otel
+			if config.WithTraceID {
+				traceID := trace.SpanFromContext(c.Request().Context()).SpanContext().TraceID().String()
+				attributes = append(attributes, slog.String("trace-id", traceID))
+			}
+			if config.WithSpanID {
+				spanID := trace.SpanFromContext(c.Request().Context()).SpanContext().SpanID().String()
+				attributes = append(attributes, slog.String("span-id", spanID))
+			}
+
 			// request
 			if config.WithRequestBody {
 				attributes = append(attributes, slog.Group("request", slog.String("body", string(reqBody))))