chore(update_channel): better errors

When creating and updating an update channel, target group ids are
validated to be available, meaning:
- they are present in the DB
- they are not related to any other update channel

closes edgehog-device-manager#529

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

backend/lib/edgehog/groups/device_group/device_group.ex

@@ -60,6 +60,14 @@ defmodule Edgehog.Groups.DeviceGroup do
       accept [:update_channel_id]
     end
 
+    update :assign_update_channel do
+      accept [:update_channel_id]
+
+      require_atomic? false
+
+      validate Validations.UpdateChannelAbsent
+    end
+
     destroy :destroy do
       description "Deletes a device group."
       primary? true

backend/lib/edgehog/groups/device_group/validations/update_channel_absent.ex

@@ -0,0 +1,38 @@
+#
+# This file is part of Edgehog.
+#
+# Copyright 2024 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.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+defmodule Edgehog.Groups.DeviceGroup.Validations.UpdateChannelAbsent do
+  @moduledoc false
+  use Ash.Resource.Validation
+
+  @impl Ash.Resource.Validation
+  def validate(changeset, _opts, _context) do
+    device_group = changeset.data
+
+    if device_group.update_channel_id do
+      {:error,
+       field: :update_channel_id,
+       message: "The update channel is already set for the device group \"#{device_group.name}\"",
+       short_message: "Update channel already set"}
+    else
+      :ok
+    end
+  end
+end

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

@@ -22,36 +22,13 @@ defmodule Edgehog.UpdateCampaigns.UpdateChannel.Changes.RelateTargetGroups do
   @moduledoc false
   use Ash.Resource.Change
 
-  alias Ash.Error.Changes.InvalidArgument
-  alias Edgehog.Groups.DeviceGroup
-
   @impl Ash.Resource.Change
-  def change(changeset, _opts, context) do
-    %{tenant: tenant} = context
-
+  def change(changeset, _opts, _context) do
     {:ok, target_group_ids} = Ash.Changeset.fetch_argument(changeset, :target_group_ids)
 
-    Ash.Changeset.after_action(changeset, fn _changeset, update_channel ->
-      relate_target_groups(tenant, update_channel, target_group_ids)
-    end)
-  end
-
-  defp relate_target_groups(tenant, update_channel, target_group_ids) do
-    %Ash.BulkResult{status: status, records: records} =
-      DeviceGroup
-      |> Ash.Query.filter(id in ^target_group_ids)
-      |> Ash.Query.filter(is_nil(update_channel_id))
-      |> Ash.Query.set_tenant(tenant)
-      |> Ash.bulk_update(:update_update_channel, %{update_channel_id: update_channel.id}, return_records?: true)
-
-    if status == :success and length(records) == length(target_group_ids) do
-      {:ok, update_channel}
-    else
-      {:error,
-       InvalidArgument.exception(
-         field: :target_group_ids,
-         message: "some target groups were not found or are already associated with an update channel"
-       )}
-    end
+    Ash.Changeset.manage_relationship(changeset, :target_groups, target_group_ids,
+      on_lookup: {:relate, :assign_update_channel},
+      on_no_match: :error
+    )
   end
 end

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

@@ -27,6 +27,7 @@ defmodule EdgehogWeb.Schema.Mutation.CreateUpdateChannelTest do
   describe "createUpdateChannel mutation" do
     test "creates update_channel with valid data", %{tenant: tenant} do
       target_group = device_group_fixture(tenant: tenant)
+      assert target_group.update_channel_id == nil
 
       target_group_id = AshGraphql.Resource.encode_relay_id(target_group)
 
@@ -176,15 +177,20 @@ defmodule EdgehogWeb.Schema.Mutation.CreateUpdateChannelTest do
 
       assert %{
                path: ["createUpdateChannel"],
-               fields: [:target_group_ids],
-               message: "some target groups were not found or are already associated with an update channel",
-               code: "invalid_argument"
+               fields: [:id],
+               message: "could not be found",
+               code: "not_found"
              } = error
     end
 
     test "fails when trying to use already assigned target groups", %{tenant: tenant} do
       target_group = device_group_fixture(tenant: tenant)
-      _ = update_channel_fixture(tenant: tenant, target_group_ids: [target_group.id])
+
+      _ =
+        update_channel_fixture(
+          tenant: tenant,
+          target_group_ids: [target_group.id]
+        )
 
       target_group_id = AshGraphql.Resource.encode_relay_id(target_group)
 
@@ -195,10 +201,12 @@ defmodule EdgehogWeb.Schema.Mutation.CreateUpdateChannelTest do
 
       assert %{
                path: ["createUpdateChannel"],
-               fields: [:target_group_ids],
-               message: "some target groups were not found or are already associated with an update channel",
-               code: "invalid_argument"
+               fields: [:update_channel_id],
+               message: "The update channel is already set for the device group " <> name,
+               code: "invalid_attribute"
              } = error
+
+      assert name == "\"#{target_group.name}\""
     end
   end
 

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

@@ -154,15 +154,17 @@ defmodule EdgehogWeb.Schema.Mutation.UpdateUpdateChannelTest do
 
       assert %{
                path: ["updateUpdateChannel"],
-               fields: [:target_group_ids],
-               code: "invalid_argument",
-               message: "some target groups were not found or are already associated with an update channel"
+               fields: [:id],
+               code: "not_found",
+               message: "could not be found"
              } = error
     end
 
     test "fails when trying to use already assigned target groups", %{tenant: tenant, id: id} do
       target_group = device_group_fixture(tenant: tenant)
-      _ = update_channel_fixture(tenant: tenant, target_group_ids: [target_group.id])
+
+      _ =
+        update_channel_fixture(tenant: tenant, target_group_ids: [target_group.id])
 
       target_group_id = AshGraphql.Resource.encode_relay_id(target_group)
 
@@ -173,10 +175,12 @@ defmodule EdgehogWeb.Schema.Mutation.UpdateUpdateChannelTest do
 
       assert %{
                path: ["updateUpdateChannel"],
-               fields: [:target_group_ids],
-               code: "invalid_argument",
-               message: "some target groups were not found or are already associated with an update channel"
+               fields: [:update_channel_id],
+               code: "invalid_attribute",
+               message: "The update channel is already set for the device group " <> name
              } = error
+
+      assert name == "\"#{target_group.name}\""
     end
   end