[#498] handler: Add spans to detail the trace

Signed-off-by: Roman Loginov <r.loginov@yadro.com>

api/handler/copy.go

@@ -6,6 +6,7 @@ import (
 	"regexp"
 	"time"
 
+	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/auth"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/data"
@@ -40,18 +41,19 @@ func path2BucketObject(path string) (string, string, error) {
 }
 
 func (h *handler) CopyObjectHandler(w http.ResponseWriter, r *http.Request) {
+	ctx, span := tracing.StartSpanFromContext(r.Context(), "handler.CopyObject")
+	defer span.End()
+
 	var (
 		err       error
 		versionID string
 		metadata  map[string]string
 		tagSet    map[string]string
-
-		ctx     = r.Context()
-		reqInfo = middleware.GetReqInfo(ctx)
-
-		cannedACLStatus = aclHeadersStatus(r)
 	)
 
+	reqInfo := middleware.GetReqInfo(ctx)
+	cannedACLStatus := aclHeadersStatus(r)
+
 	src := r.Header.Get(api.AmzCopySource)
 	// Check https://docs.aws.amazon.com/AmazonS3/latest/dev/ObjectVersioning.html
 	// Regardless of whether you have enabled versioning, each object in your bucket