chore(update_channels): allow empty targets

Update channels can have zero target device groups.
Closes #399 and Closes #518.

Signed-off-by: Luca Zaninotto <[email protected]>

backend/lib/edgehog/update_campaigns/update_channel/changes/relate_target_groups.ex

@@ -1,7 +1,7 @@
 #
 # This file is part of Edgehog.
 #
-# Copyright 2025 SECO Mind Srl
+# Copyright 2024-2025 SECO Mind Srl
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.

backend/lib/edgehog/update_campaigns/update_channel/update_channel.ex

@@ -58,9 +58,6 @@ defmodule Edgehog.UpdateCampaigns.UpdateChannel do
         description """
         The IDs of the target groups that are targeted by this update channel.
         """
-
-        allow_nil? false
-        constraints min_length: 1
       end
 
       change Changes.RelateTargetGroups do
@@ -78,16 +75,13 @@ defmodule Edgehog.UpdateCampaigns.UpdateChannel do
         description """
         The IDs of the target groups that are targeted by this update channel.
         """
-
-        constraints min_length: 1
       end
 
       # Needed because manage_relationship is not atomic
       require_atomic? false
 
-      change Changes.UnrelateCurrentTargetGroups do
-        where present(:target_group_ids)
-      end
+      # Always unrelate target groups
+      change Changes.UnrelateCurrentTargetGroups
 
       change Changes.RelateTargetGroups do
         where present(:target_group_ids)

backend/mix.lock.license

@@ -1,2 +1,2 @@
-SPDX-FileCopyrightText: 2021-2024 SECO Mind Srl
+SPDX-FileCopyrightText: 2021-2025 SECO Mind Srl
 SPDX-License-Identifier: CC0-1.0

backend/test/edgehog_web/schema/mutation/create_update_channel_test.exs

@@ -49,6 +49,34 @@ defmodule EdgehogWeb.Schema.Mutation.CreateUpdateChannelTest do
       assert target_group_data["handle"] == target_group.handle
     end
 
+    test "creates update_channel with nil target_group_ids", %{tenant: tenant} do
+      name = unique_update_channel_name()
+      handle = unique_update_channel_handle()
+
+      result =
+        [target_group_ids: nil, tenant: tenant, name: name, handle: handle]
+        |> create_update_channel_mutation()
+        |> extract_result!()
+
+      assert result["name"] == name
+      assert result["handle"] == handle
+      assert result["targetGroups"] == []
+    end
+
+    test "creates update_channel with empty target_group_ids", %{tenant: tenant} do
+      name = unique_update_channel_name()
+      handle = unique_update_channel_handle()
+
+      result =
+        [target_group_ids: [], tenant: tenant, name: name, handle: handle]
+        |> create_update_channel_mutation()
+        |> extract_result!()
+
+      assert result["name"] == name
+      assert result["handle"] == handle
+      assert result["targetGroups"] == []
+    end
+
     test "fails with missing name", %{tenant: tenant} do
       error =
         [name: nil, tenant: tenant]
@@ -143,30 +171,6 @@ defmodule EdgehogWeb.Schema.Mutation.CreateUpdateChannelTest do
              } = error
     end
 
-    test "fails with missing target_group_ids", %{tenant: tenant} do
-      error =
-        [target_group_ids: nil, tenant: tenant]
-        |> create_update_channel_mutation()
-        |> extract_error!()
-
-      assert %{message: message} = error
-      assert message =~ ~s<In field "targetGroupIds": Expected type "[ID!]!", found null.>
-    end
-
-    test "fails with empty target_group_ids", %{tenant: tenant} do
-      error =
-        [target_group_ids: [], tenant: tenant]
-        |> create_update_channel_mutation()
-        |> extract_error!()
-
-      assert %{
-               path: ["createUpdateChannel"],
-               fields: [:target_group_ids],
-               message: "must have 1 or more items",
-               code: "invalid_argument"
-             } = error
-    end
-
     test "fails when trying to use a non-existing target group", %{tenant: tenant} do
       target_group_id = non_existing_device_group_id(tenant)
 

backend/test/edgehog_web/schema/mutation/update_update_channel_test.exs

@@ -130,18 +130,13 @@ defmodule EdgehogWeb.Schema.Mutation.UpdateUpdateChannelTest do
              } = error
     end
 
-    test "fails with empty target_group_ids", %{tenant: tenant, id: id} do
-      error =
+    test "updates update_channel with empty target_group_ids", %{tenant: tenant, id: id} do
+      result =
         [id: id, target_group_ids: [], tenant: tenant]
         |> update_update_channel_mutation()
-        |> extract_error!()
+        |> extract_result!()
 
-      assert %{
-               path: ["updateUpdateChannel"],
-               fields: [:target_group_ids],
-               code: "invalid_argument",
-               message: "must have 1 or more items"
-             } = error
+      assert result["id"] == id
     end
 
     test "fails when trying to use a non-existing target group id", %{tenant: tenant, id: id} do