Add indicators of running jobs in maintenance page

lib/music_library_web/live/maintenance_live/index.ex

@@ -1,19 +1,65 @@
 defmodule MusicLibraryWeb.MaintenanceLive.Index do
   use MusicLibraryWeb, :live_view
 
+  import Ecto.Query
+
   require Logger
 
   alias MusicLibrary.Artists
+  alias MusicLibrary.BackgroundRepo
   alias MusicLibrary.Records
   alias MusicLibrary.Repo
 
+  @poll_interval 2_000
+
   def mount(_params, _session, socket) do
+    if connected?(socket) do
+      Process.send_after(self(), :update_job_counts, @poll_interval)
+    end
+
     {:ok,
      socket
      |> assign(
        page_title: gettext("Maintenance"),
        current_section: :maintenance
-     )}
+     )
+     |> assign_job_counts()}
+  end
+
+  def handle_info(:update_job_counts, socket) do
+    Process.send_after(self(), :update_job_counts, @poll_interval)
+
+    {:noreply, assign_job_counts(socket)}
+  end
+
+  defp assign_job_counts(socket) do
+    socket
+    |> assign(
+      :refresh_records_musicbrainz_jobs,
+      count_jobs("MusicLibrary.Worker.RecordRefreshMusicBrainzData")
+    )
+    |> assign(
+      :generate_record_embeddings_jobs,
+      count_jobs("MusicLibrary.Worker.GenerateRecordEmbedding")
+    )
+    |> assign(
+      :refresh_artists_musicbrainz_jobs,
+      count_jobs("MusicLibrary.Worker.ArtistRefreshMusicBrainzData")
+    )
+    |> assign(
+      :refresh_artists_discogs_jobs,
+      count_jobs("MusicLibrary.Worker.ArtistRefreshDiscogsData")
+    )
+  end
+
+  defp count_jobs(worker) do
+    query =
+      from j in Oban.Job,
+        where: j.worker == ^worker,
+        where: j.state in ["available", "scheduled", "executing", "retryable"],
+        select: count(j.id)
+
+    BackgroundRepo.one(query)
   end
 
   def handle_event("refresh_records_musicbrainz_data", _params, socket) do