Proxy WASM track traffic through DeepDrftPublic to DeepDrftAPI

2026-05-25 19:11:00 -04:00
parent 02e230e236
commit e2a7944077
4 changed files with 121 additions and 15 deletions
@@ -0,0 +1,108 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace DeepDrftPublic.Controllers;
+
+/// <summary>
+/// Proxies public track API calls to DeepDrftAPI so the browser never makes
+/// cross-origin requests. The WASM client points both named HttpClients at
+/// this host; this controller forwards unauthenticated public routes upstream.
+/// SSR prerender calls DeepDrftAPI directly (server-to-server) via the same
+/// named clients — no proxy hop needed on the server side.
+/// </summary>
+[ApiController]
+[Route("api/[controller]")]
+public class TrackController : ControllerBase
+{
+    private readonly HttpClient _upstream;
+    private readonly ILogger<TrackController> _logger;
+
+    public TrackController(IHttpClientFactory httpClientFactory, ILogger<TrackController> logger)
+    {
+        _upstream = httpClientFactory.CreateClient("DeepDrft.API");
+        _logger = logger;
+    }
+
+    /// <summary>Proxies paged track metadata from DeepDrftAPI.</summary>
+    [HttpGet("page")]
+    public async Task<ActionResult> GetPage(
+        [FromQuery] int page = 1,
+        [FromQuery] int pageSize = 20,
+        [FromQuery] string? sortColumn = null,
+        [FromQuery] bool sortDescending = false,
+        CancellationToken ct = default)
+    {
+        var query = $"api/track/page?page={page}&pageSize={pageSize}&sortDescending={sortDescending}";
+        if (!string.IsNullOrWhiteSpace(sortColumn))
+            query += $"&sortColumn={Uri.EscapeDataString(sortColumn)}";
+
+        HttpResponseMessage upstream;
+        try
+        {
+            upstream = await _upstream.GetAsync(query, HttpCompletionOption.ResponseHeadersRead, ct);
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Upstream call to DeepDrftAPI track/page failed");
+            return StatusCode(502, "Upstream unavailable");
+        }
+
+        using (upstream)
+        {
+            if (!upstream.IsSuccessStatusCode)
+            {
+                _logger.LogWarning("DeepDrftAPI track/page returned {Status}", (int)upstream.StatusCode);
+                return StatusCode((int)upstream.StatusCode);
+            }
+
+            var json = await upstream.Content.ReadAsStringAsync(ct);
+            return Content(json, "application/json");
+        }
+    }
+
+    /// <summary>
+    /// Proxies audio streaming from DeepDrftAPI. Passes the optional byte offset
+    /// so seek-beyond-buffer works through the proxy without buffering.
+    /// </summary>
+    [HttpGet("{trackId}")]
+    public async Task<ActionResult> GetTrack(
+        string trackId,
+        [FromQuery] long offset = 0,
+        CancellationToken ct = default)
+    {
+        _logger.LogInformation("Proxying track {TrackId} offset {Offset}", trackId, offset);
+
+        var path = offset == 0
+            ? $"api/track/{Uri.EscapeDataString(trackId)}"
+            : $"api/track/{Uri.EscapeDataString(trackId)}?offset={offset}";
+
+        HttpResponseMessage upstream;
+        try
+        {
+            upstream = await _upstream.GetAsync(path, HttpCompletionOption.ResponseHeadersRead, ct);
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Upstream call to DeepDrftAPI track/{TrackId} failed", trackId);
+            return StatusCode(502, "Upstream unavailable");
+        }
+
+        if (!upstream.IsSuccessStatusCode)
+        {
+            upstream.Dispose();
+            _logger.LogWarning("DeepDrftAPI track/{TrackId} returned {Status}", trackId, (int)upstream.StatusCode);
+            return StatusCode((int)upstream.StatusCode);
+        }
+
+        // Do NOT dispose upstream here — File() takes ownership of the response stream
+        // and disposes it after the body is sent.
+        var contentType = upstream.Content.Headers.ContentType?.ToString() ?? "audio/wav";
+        var contentLength = upstream.Content.Headers.ContentLength;
+
+        // Forward Content-Length so the WASM player has duration info from the WAV header length.
+        if (contentLength.HasValue)
+            Response.ContentLength = contentLength.Value;
+
+        var stream = await upstream.Content.ReadAsStreamAsync(ct);
+        return File(stream, contentType, enableRangeProcessing: false);
+    }
+}