fix(storage): fix Azure Blob dump failing with file does not exist (#38814) (#38828)

backport #38814

modules/storage/storage.go

@@ -11,11 +11,13 @@ import (
 	"net/url"
 	"os"
 	"path"
+	"strings"
 
 	"gitea.dev/modules/httplib"
 	"gitea.dev/modules/log"
 	"gitea.dev/modules/public"
 	"gitea.dev/modules/setting"
+	"gitea.dev/modules/util"
 )
 
 // ErrURLNotSupported represents url is not supported
@@ -139,6 +141,23 @@ func SaveFrom(objStorage ObjectStorage, path string, callback func(w io.Writer)
 	return err
 }
 
+func buildObjectStorePath(base, p string) string {
+	p = strings.TrimPrefix(util.PathJoinRelX(base, p), "/") // object store doesn't use slash for root path
+	if p == "." {
+		p = "" // object store doesn't use dot as relative path
+	}
+	return p
+}
+
+func buildObjectStorePathPrefix(base, p string) string {
+	// ending slash is required for avoiding matching like "foo/" and "foobar/" with prefix "foo"
+	p = buildObjectStorePath(base, p) + "/"
+	if p == "/" {
+		p = "" // object store doesn't use slash for root path
+	}
+	return p
+}
+
 var (
 	// Attachments represents attachments storage
 	Attachments ObjectStorage = uninitializedStorage