From 4d11aa8655aa3d010193cf1b42293c2c42ec33d3 Mon Sep 17 00:00:00 2001
From: Oscar Zhou <100548325+oscarzhou-portainer@users.noreply.github.com>
Date: Thu, 10 Jul 2025 00:55:59 +1200
Subject: [PATCH] fix(tag): ignore "environment not found" when deleting tag
 [BE-11944] (#869)

---
 api/http/handler/tags/tag_delete.go      |  3 +++
 api/http/handler/tags/tag_delete_test.go | 25 ++++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/api/http/handler/tags/tag_delete.go b/api/http/handler/tags/tag_delete.go
index 1fa98e394..5e67c4f4c 100644
--- a/api/http/handler/tags/tag_delete.go
+++ b/api/http/handler/tags/tag_delete.go
@@ -59,6 +59,9 @@ func deleteTag(tx dataservices.DataStoreTx, tagID portainer.TagID) error {
 
 	for endpointID := range tag.Endpoints {
 		endpoint, err := tx.Endpoint().Endpoint(endpointID)
+		if tx.IsErrObjectNotFound(err) {
+			continue
+		}
 		if err != nil {
 			return httperror.InternalServerError("Unable to retrieve environment from the database", err)
 		}
diff --git a/api/http/handler/tags/tag_delete_test.go b/api/http/handler/tags/tag_delete_test.go
index cabf20963..a215e7edd 100644
--- a/api/http/handler/tags/tag_delete_test.go
+++ b/api/http/handler/tags/tag_delete_test.go
@@ -84,3 +84,28 @@ func TestTagDeleteEdgeGroupsConcurrently(t *testing.T) {
 		t.Fatal("the edge group is not consistent")
 	}
 }
+
+func TestDeleteTag(t *testing.T) {
+	_, store := datastore.MustNewTestStore(t, true, false)
+
+	// Test the tx.IsErrObjectNotFound logic when endpoint is not found during cleanup
+	t.Run("should continue gracefully when endpoint not found during cleanup", func(t *testing.T) {
+		// Create a tag with a reference to a non-existent endpoint
+		tag := &portainer.Tag{
+			ID:             1,
+			Name:           "test-tag",
+			Endpoints:      map[portainer.EndpointID]bool{999: true}, // Non-existent endpoint
+			EndpointGroups: make(map[portainer.EndpointGroupID]bool),
+		}
+
+		err := store.Tag().Create(tag)
+		if err != nil {
+			t.Fatal("could not create tag:", err)
+		}
+
+		err = deleteTag(store, 1)
+		if err != nil {
+			t.Fatal("could not delete tag:", err)
+		}
+	})
+}