Simplify mirror repository API logic (#30963)

Fix #30921

(cherry picked from commit 821d2fc2a3cc897f21d707455850177077b72410)

modules/structs/repo.go

@@ -230,7 +230,7 @@ type EditRepoOption struct {
 	Archived *bool `json:"archived,omitempty"`
 	// set to a string like `8h30m0s` to set the mirror interval time
 	MirrorInterval *string `json:"mirror_interval,omitempty"`
-	// enable prune - remove obsolete remote-tracking references
+	// enable prune - remove obsolete remote-tracking references when mirroring
 	EnablePrune *bool `json:"enable_prune,omitempty"`
 }
 

routers/api/v1/repo/repo.go

@@ -1072,16 +1072,10 @@ func updateRepoArchivedState(ctx *context.APIContext, opts api.EditRepoOption) e
 func updateMirror(ctx *context.APIContext, opts api.EditRepoOption) error {
 	repo := ctx.Repo.Repository
 
-	// only update mirror if interval or enable prune are provided
-	if opts.MirrorInterval == nil && opts.EnablePrune == nil {
-		return nil
-	}
-
-	// these values only make sense if the repo is a mirror
+	// Skip this update if the repo is not a mirror, do not return error.
+	// Because reporting errors only makes the logic more complex&fragile, it doesn't really help end users.
 	if !repo.IsMirror {
-		err := fmt.Errorf("repo is not a mirror, can not change mirror interval")
-		ctx.Error(http.StatusUnprocessableEntity, err.Error(), err)
-		return err
+		return nil
 	}
 
 	// get the mirror from the repo

templates/swagger/v1_json.tmpl

@@ -21160,7 +21160,7 @@
           "x-go-name": "Description"
         },
         "enable_prune": {
-          "description": "enable prune - remove obsolete remote-tracking references",
+          "description": "enable prune - remove obsolete remote-tracking references when mirroring",
           "type": "boolean",
           "x-go-name": "EnablePrune"
         },