feat: add unified file management with upload and download requests

backend/lib/edgehog/devices/device/device.ex

@@ -62,7 +62,8 @@ defmodule Edgehog.Devices.Device do
     paginate_relationship_with application_deployments: :relay,
                                ota_operations: :relay,
                                tags: :relay,
-                               file_download_requests: :relay
+                               file_download_requests: :relay,
+                               file_upload_requests: :relay
 
     subscriptions do
       pubsub EdgehogWeb.Endpoint
@@ -508,6 +509,12 @@ defmodule Edgehog.Devices.Device do
       writable? false
     end
 
+    has_many :file_upload_requests, Edgehog.Files.FileUploadRequest do
+      public? true
+      description "The existing file upload requests for this device"
+      writable? false
+    end
+
     has_many :application_deployments, Deployment do
       public? true
     end

backend/lib/edgehog/files/file_upload_request/calculations/get_presigned_url.ex

@@ -0,0 +1,58 @@
+#
+# This file is part of Edgehog.
+#
+# Copyright 2026 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.Files.FileUploadRequest.Calculations.GetPresignedUrl do
+  @moduledoc false
+  use Ash.Resource.Calculation
+
+  alias Ash.Resource.Calculation
+
+  @files_storage_module Application.compile_env(
+                          :edgehog,
+                          :files_storage_module,
+                          Edgehog.Storage
+                        )
+
+  @impl Calculation
+  def load(_query, _opts, _context) do
+    [:id]
+  end
+
+  @impl Calculation
+  def calculate(records, _opts, context) do
+    tenant_id = extract_tenant_id(context)
+
+    Enum.map(records, fn file_upload_request ->
+      file_path =
+        "uploads/tenants/#{tenant_id}/file_upload_requests/#{file_upload_request.id}"
+
+      case @files_storage_module.read_presigned_url(file_path) do
+        {:ok, %{get_url: get_url}} -> get_url
+        {:error, _reason} -> nil
+      end
+    end)
+  end
+
+  # Ash context can carry tenant as a struct in request flows or as a raw id in
+  # background executor flows, so we support both shapes to avoid crashes.
+  defp extract_tenant_id(%{tenant: %{tenant_id: tenant_id}}), do: tenant_id
+  defp extract_tenant_id(%{tenant: tenant_id}), do: tenant_id
+  defp extract_tenant_id(_), do: nil
+end

backend/lib/edgehog/files/file_upload_request/file_upload_request.ex

@@ -22,20 +22,42 @@ defmodule Edgehog.Files.FileUploadRequest do
   @moduledoc false
   use Edgehog.MultitenantResource,
     domain: Edgehog.Files,
-    extensions: [AshGraphql.Resource]
+    extensions: [AshGraphql.Resource],
+    notifiers: [Ash.Notifier.PubSub]
 
+  alias Edgehog.Files.FileUploadRequest.Calculations
   alias Edgehog.Files.FileUploadRequest.Changes
   alias Edgehog.Files.FileUploadRequest.FileSource
   alias Edgehog.Files.FileUploadRequest.ManualActions
   alias Edgehog.Files.FileUploadRequest.Status
 
   graphql do
     type :file_upload_request
+
+    subscriptions do
+      pubsub EdgehogWeb.Endpoint
+
+      subscribe :file_upload_requests do
+        action_types [:create, :update]
+      end
+
+      subscribe :file_upload_requests_by_device do
+        action_types [:create, :update]
+        read_action :read_by_device
+        relay_id_translations device_id: :device
+      end
+    end
   end
 
   actions do
     defaults [:read, :destroy]
 
+    read :read_by_device do
+      argument :device_id, :id, allow_nil?: false
+
+      get_by :device_id
+    end
+
     create :send_request do
       accept [:source, :source_type, :compression, :progress_tracked, :http_headers]
 
@@ -160,6 +182,16 @@ defmodule Edgehog.Files.FileUploadRequest do
     end
   end
 
+  calculations do
+    calculate :get_presigned_url, :string do
+      public? true
+
+      description "Get a presigned URL for downloading the uploaded file. The URL is valid for a limited time."
+
+      calculation Calculations.GetPresignedUrl
+    end
+  end
+
   postgres do
     table "file_upload_requests"
     repo Edgehog.Repo