fix(rm): faulty checks for existing database resources

There were some faulty checks for existing database resources, due
to the used `Repo.some?` custom function which now returns a `{:ok,
bool}` tuple instead of directly a boolean, as in previous iterations.

Indeed, the tuple was either checked in `if` statements where it always
computed to a trueish value, of it was pattern matched to boolean values
which resulted in an match error and a crash.

The latter one is also the case of a bug in the DeviceRemover task,
which crashed just after launch and resulted in devices to be
stuck in the "in deletion"
status.

Fixes astarte-platform#1493.

Signed-off-by: Davide Briani <davide.briani@secomind.com>

Author: davidebriani

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+
+## [1.2.1] - Unreleased
+### Fixed
+- [astarte_realm_management] Faulty checks for existing database resources. This fix also addresses a bug where devices got stuck in the "in deletion" status: [#1493](https://github.com/astarte-platform/astarte/issues/1493).
+
 ## [1.2.1-rc.0] - 2025-08-26
 ### Added
 - New environment variables to control how clustering work, needed on AppEngine and DUP.

apps/astarte_realm_management/lib/astarte_realm_management/device_removal/core.ex

@@ -36,10 +36,9 @@ defmodule Astarte.RealmManagement.DeviceRemoval.Core do
   end
 
   defp retrieve_individual_datastreams_keys!(realm_name, device_id) do
-    if Queries.table_exist?(realm_name, "individual_datastreams") do
-      Queries.retrieve_individual_datastreams_keys!(realm_name, device_id)
-    else
-      []
+    case Queries.table_exist?(realm_name, "individual_datastreams") do
+      {:ok, true} -> Queries.retrieve_individual_datastreams_keys!(realm_name, device_id)
+      {:ok, false} -> []
     end
   end
 
@@ -69,10 +68,9 @@ defmodule Astarte.RealmManagement.DeviceRemoval.Core do
   end
 
   defp retrieve_individual_properties_keys!(realm_name, device_id) do
-    if Queries.table_exist?(realm_name, "individual_properties") do
-      Queries.retrieve_individual_properties_keys!(realm_name, device_id)
-    else
-      []
+    case Queries.table_exist?(realm_name, "individual_properties") do
+      {:ok, true} -> Queries.retrieve_individual_properties_keys!(realm_name, device_id)
+      {:ok, false} -> []
     end
   end
 

apps/astarte_realm_management/lib/astarte_realm_management/device_removal/device_remover.ex

@@ -33,8 +33,8 @@ defmodule Astarte.RealmManagement.DeviceRemoval.DeviceRemover do
   @spec run(%{:device_id => <<_::128>>, :realm_name => binary()}) :: :ok | no_return()
   def run(%{realm_name: realm_name, device_id: device_id} = args) do
     case Queries.check_device_exists(realm_name, device_id) do
-      true -> do_run(args)
-      false -> cleanup(args)
+      {:ok, true} -> do_run(args)
+      {:ok, false} -> cleanup(args)
     end
   end
 

apps/astarte_realm_management/test/astarte_realm_management/device_removal/core_test.exs

@@ -67,6 +67,22 @@ defmodule Astarte.RealmManagement.DeviceRemover.CoreTest do
       end
     end
 
+    property "delete_individual_datastream/2 does not crash when individual datastream table is missing",
+             %{realm: realm} do
+      keyspace = Realm.keyspace_name(realm)
+
+      Ecto.Migrator.run(Repo, [{0, CreateDatastreamIndividualMultiInterface}], :up,
+        prefix: keyspace,
+        all: true
+      )
+
+      Repo.query!("DROP TABLE #{keyspace}.individual_datastreams;")
+
+      check all(device_id <- Astarte.Core.Generators.Device.id()) do
+        Core.delete_individual_datastreams!(realm, device_id)
+      end
+    end
+
     property "delete_individual_properties/2 removes individual properties data of a valid device",
              %{realm: realm} do
       keyspace = Realm.keyspace_name(realm)
@@ -88,6 +104,17 @@ defmodule Astarte.RealmManagement.DeviceRemover.CoreTest do
       end
     end
 
+    property "delete_individual_properties/2 does not crash when individual properties table is missing",
+             %{realm: realm} do
+      keyspace = Realm.keyspace_name(realm)
+
+      Repo.query!("DROP TABLE #{keyspace}.individual_properties;")
+
+      check all(device_id <- Astarte.Core.Generators.Device.id()) do
+        Core.delete_individual_properties!(realm, device_id)
+      end
+    end
+
     property "delete_object_datastream/2 removes object datastreams of a valid device", %{
       realm: realm
     } do