refactor: improve json encoding performance

go.mod

@@ -6,6 +6,7 @@ replace github.com/projectcontour/contour => github.com/snapp-incubator/contour
 
 require (
 	github.com/go-logr/logr v1.2.4
+	github.com/json-iterator/go v1.1.12
 	github.com/labstack/echo/v4 v4.11.2
 	github.com/onsi/ginkgo/v2 v2.13.0
 	github.com/onsi/gomega v1.28.0
@@ -56,7 +57,6 @@ require (
 	github.com/imdario/mergo v0.3.12 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
-	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/labstack/gommon v0.4.0 // indirect
 	github.com/magiconair/properties v1.8.7 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect

internal/webhook/validate_test.go

@@ -2,7 +2,6 @@ package webhook
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/http/httptest"

internal/webhook/webhook.go

@@ -1,13 +1,13 @@
 package webhook
 
 import (
-	"encoding/json"
 	"fmt"
 	"io"
 	"net"
 	"net/http"
 	"time"
 
+	jsoniter "github.com/json-iterator/go"
 	"github.com/labstack/echo/v4"
 	contourv1 "github.com/projectcontour/contour/apis/projectcontour/v1"
 	"github.com/snapp-incubator/contour-admission-webhook/internal/cache"
@@ -26,6 +26,8 @@ var (
 	codecFactory = serializer.NewCodecFactory(scheme)
 	deserializer = codecFactory.UniversalDeserializer()
 
+	json = jsoniter.ConfigCompatibleWithStandardLibrary
+
 	entryTtlSecond int
 
 	logger = ctrl.Log.WithName("webhook")