MM_22682_Centralize_ID_Validation (#14237)

Co-authored-by: mattermod <mattermod@users.noreply.github.com>

model/reaction.go

@@ -64,11 +64,11 @@ func ReactionsFromJson(data io.Reader) []*Reaction {
 }
 
 func (o *Reaction) IsValid() *AppError {
-	if len(o.UserId) != 26 {
+	if !IsValidId(o.UserId) {
 		return NewAppError("Reaction.IsValid", "model.reaction.is_valid.user_id.app_error", nil, "user_id="+o.UserId, http.StatusBadRequest)
 	}
 
-	if len(o.PostId) != 26 {
+	if !IsValidId(o.PostId) {
 		return NewAppError("Reaction.IsValid", "model.reaction.is_valid.post_id.app_error", nil, "post_id="+o.PostId, http.StatusBadRequest)
 	}