server/api.go

@@ -1536,6 +1536,10 @@ func (p *Plugin) getUserBadges(w http.ResponseWriter, r *http.Request, actingUse
 		p.mm.Log.Debug("Error getting the badges for user", "error", err, "user", userID)
 	}
 
+	for _, ub := range badges {
+		p.sanitizeBadgeEmoji(&ub.Badge)
+	}
+
 	b, _ := json.Marshal(badges)
 	_, _ = w.Write(b)
 }
@@ -1564,6 +1568,7 @@ func (p *Plugin) getBadgeDetails(w http.ResponseWriter, r *http.Request, actingU
 
 	resp := BadgeDetailsResponse{BadgeDetails: badge}
 	if badge != nil {
+		p.sanitizeBadgeEmoji(&badge.Badge)
 		actingUser, userErr := p.mm.User.Get(actingUserID)
 		if userErr == nil {
 			bt, typeErr := p.store.GetType(badge.Type)
@@ -1578,12 +1583,16 @@ func (p *Plugin) getBadgeDetails(w http.ResponseWriter, r *http.Request, actingU
 }
 
 func (p *Plugin) getAllBadges(w http.ResponseWriter, r *http.Request, actingUserID string) {
-	badge, err := p.store.GetAllBadges()
+	badges, err := p.store.GetAllBadges()
 	if err != nil {
 		p.mm.Log.Debug("Cannot get all badges", "error", err)
 	}
 
-	b, _ := json.Marshal(badge)
+	for _, ab := range badges {
+		p.sanitizeBadgeEmoji(&ab.Badge)
+	}
+
+	b, _ := json.Marshal(badges)
 	_, _ = w.Write(b)
 }
 

server/utils.go

@@ -140,6 +140,27 @@ func dumpObject(o interface{}) {
 	fmt.Println(string(b))
 }
 
+const fallbackEmoji = "question"
+
+// sanitizeBadgeEmoji checks if a badge's custom emoji still exists.
+// If the emoji was deleted, it replaces it with a fallback and persists the change.
+func (p *Plugin) sanitizeBadgeEmoji(badge *badgesmodel.Badge) {
+	if badge.ImageType != badgesmodel.ImageTypeEmoji {
+		return
+	}
+	if _, ok := model.SystemEmojis[badge.Image]; ok {
+		return
+	}
+	_, appErr := p.API.GetEmojiByName(badge.Image)
+	if appErr == nil {
+		return
+	}
+	badge.Image = fallbackEmoji
+	if err := p.store.UpdateBadge(badge); err != nil {
+		p.mm.Log.Warn("Failed to replace deleted emoji on badge", "badge_id", badge.ID, "error", err.Error())
+	}
+}
+
 func (p *Plugin) notifyGrant(badgeID badgesmodel.BadgeID, granter string, granted *model.User, inChannel bool, channelID string, reason string) {
 	b, errBadge := p.store.GetBadgeDetails(badgeID)
 	granterUser, errUser := p.mm.User.Get(granter)