14722 - removing unnecessary arn check that breaks assume role feature in other AWS partitions

pkg/tsdb/cloudwatch/credentials.go

@@ -3,7 +3,6 @@ package cloudwatch
 import (
 	"fmt"
 	"os"
-	"strings"
 	"sync"
 	"time"
 
@@ -43,7 +42,7 @@ func GetCredentials(dsInfo *DatasourceInfo) (*credentials.Credentials, error) {
 	secretAccessKey := ""
 	sessionToken := ""
 	var expiration *time.Time = nil
-	if dsInfo.AuthType == "arn" && strings.Index(dsInfo.AssumeRoleArn, "arn:aws:iam:") == 0 {
+	if dsInfo.AuthType == "arn" {
 		params := &sts.AssumeRoleInput{
 			RoleArn:         aws.String(dsInfo.AssumeRoleArn),
 			RoleSessionName: aws.String("GrafanaSession"),