Generate thumbnails

NostrStreamer/Services/ThumbnailGenerator.cs

@@ -0,0 +1,47 @@
+using Microsoft.EntityFrameworkCore;
+using NostrStreamer.Database;
+
+namespace NostrStreamer.Services;
+
+public class ThumbnailGenerator : BackgroundService
+{
+    private readonly IServiceScopeFactory _scopeFactory;
+    private readonly ILogger<ThumbnailGenerator> _logger;
+    
+    public ThumbnailGenerator(IServiceScopeFactory scopeFactory, ILogger<ThumbnailGenerator> logger)
+    {
+        _scopeFactory = scopeFactory;
+        _logger = logger;
+    }
+    
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            try
+            {
+                using var scope = _scopeFactory.CreateScope();
+                var db = scope.ServiceProvider.GetRequiredService<StreamerContext>();
+                var gen = scope.ServiceProvider.GetRequiredService<ThumbnailService>();
+
+                var streams = await db.Streams
+                    .AsNoTracking()
+                    .Include(a => a.Endpoint)
+                    .Include(a => a.User)
+                    .Where(a => a.State == UserStreamState.Live)
+                    .ToListAsync(cancellationToken: stoppingToken);
+
+                foreach (var stream in streams)
+                {
+                    await gen.GenerateThumb(stream);
+                }
+            }
+            catch (Exception ex)
+            {
+                _logger.LogWarning("Failed to generate thumbnail {msg}", ex.Message);
+            }
+
+            await Task.Delay(TimeSpan.FromMinutes(1), stoppingToken);
+        }
+    }
+}