Improve awsecr parseRegion method.

Signed-off-by: 疯魔慕薇 <kfanjian@gmail.com>

src/replication/adapter/awsecr/adapter.go

@@ -31,6 +31,14 @@ import (
 	"github.com/goharbor/harbor/src/replication/model"
 )
 
+const (
+	regionPattern = "https://(?:api|\\d+\\.dkr)\\.ecr\\.([\\w\\-]+)\\.amazonaws\\.com"
+)
+
+var (
+	regionRegexp = regexp.MustCompile(regionPattern)
+)
+
 func init() {
 	if err := adp.RegisterFactory(model.RegistryTypeAwsEcr, func(registry *model.Registry) (adp.Adapter, error) {
 		return newAdapter(registry)
@@ -59,8 +67,7 @@ func newAdapter(registry *model.Registry) (*adapter, error) {
 }
 
 func parseRegion(url string) (string, error) {
-	pattern := "https://(?:api|\\d+\\.dkr)\\.ecr\\.([\\w\\-]+)\\.amazonaws\\.com"
-	rs := regexp.MustCompile(pattern).FindStringSubmatch(url)
+	rs := regionRegexp.FindStringSubmatch(url)
 	if rs == nil {
 		return "", errors.New("Bad aws url")
 	}

src/replication/adapter/awsecr/adapter_test.go

@@ -1,11 +1,13 @@
 package awsecr
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
+	"regexp"
 	"testing"
 	"time"
 
@@ -251,3 +253,33 @@ func TestAwsAuthCredential_Modify(t *testing.T) {
 	err = a.Modify(req)
 	assert.Nil(t, err)
 }
+
+var urlForBenchmark = []string{
+	"https://1234.dkr.ecr.test-region.amazonaws.com/v2/",
+	"https://api.ecr.test-region.amazonaws.com",
+	"https://test-region.amazonaws.com",
+}
+
+func compileRegexpEveryTime(url string) (string, error) {
+	rs := regexp.MustCompile(regionPattern).FindStringSubmatch(url)
+	if rs == nil {
+		return "", errors.New("Bad aws url")
+	}
+	return rs[1], nil
+}
+
+func BenchmarkGetRegion(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		for _, url := range urlForBenchmark {
+			parseRegion(url)
+		}
+	}
+}
+
+func BenchmarkCompileRegexpEveryTime(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		for _, url := range urlForBenchmark {
+			compileRegexpEveryTime(url)
+		}
+	}
+}