Files
Musify/backend/Core/Musify.Infrastructure/Services/StreamTicketService.cs
T
Admin 356e5c1101 Add anonymous playback with an optional Spotify-style preview cap
New Playback:AllowAnonymousListening / Playback:AnonymousFragmentSeconds
settings control whether a request without a session can stream at all,
and if so, whether it's limited to a fragment instead of the full track:

- GET /tracks/{id}/stream and GET /youtube/tracks/{videoId}/stream no
  longer require authorization outright; the handlers gate on the config
  instead, so both keep working exactly as before when it's off (the
  default).
- The fragment cap is enforced by the Streaming Gateway, not the client:
  the stream ticket now carries an optional maxBytes claim (computed from
  AnonymousFragmentSeconds and the transcoder's known bitrate), and
  TicketValidationMiddleware clamps the Range it forwards to SeaweedFS to
  stay under it — synthesizing one if the request didn't send one, and
  answering 416 outright if the requested range starts past the cap.
- A YouTube track that hasn't been provisioned server-side yet streams
  straight from YouTube's CDN, bypassing the Gateway entirely — there's no
  way to cap that, so an anonymous request for one is refused (409) instead
  of silently handing out an uncapped stream.
- ListeningHistory has a non-nullable UserId, so anonymous plays simply
  don't get recorded rather than trying to force a row through the FK.

Also fixes a real, pre-existing bug this surfaced: the AppSettings.Development.json
of the Api, Worker, and StreamingGateway all pointed StreamTicket/Workers
paths at "../../deploy/..." — one directory short of deploy/'s actual
location at the repo root relative to each project's own folder. Docker
never hit this (it mounts an absolute /keys path), so it had apparently
never been exercised via `dotnet run` before.
2026-09-10 09:56:57 +02:00

55 lines
2.0 KiB
C#

using System.Security.Cryptography;
using Microsoft.IdentityModel.JsonWebTokens;
using Microsoft.IdentityModel.Tokens;
using Musify.Application.Contracts;
using Musify.Infrastructure.Configuration;
namespace Musify.Infrastructure.Services
{
public sealed class StreamTicketService : IStreamTicketService, IDisposable
{
private readonly StreamTicketConfiguration configuration;
private readonly RSA rsa;
private readonly SigningCredentials signingCredentials;
private readonly JsonWebTokenHandler tokenHandler = new();
public StreamTicketService(StreamTicketConfiguration configuration)
{
this.configuration = configuration;
rsa = RSA.Create();
rsa.ImportFromPem(File.ReadAllText(configuration.PrivateKeyPath));
var key = new RsaSecurityKey(rsa);
signingCredentials = new SigningCredentials(key, SecurityAlgorithms.RsaSha256);
}
public StreamTicket IssueTicket(long? userId, string keyPrefix, long? maxBytes = null)
{
var now = DateTimeOffset.UtcNow;
var claims = new Dictionary<string, object> { ["prefix"] = keyPrefix };
if (userId is not null)
claims["sub"] = userId.Value.ToString();
if (maxBytes is not null)
claims["maxBytes"] = maxBytes.Value.ToString();
var descriptor = new SecurityTokenDescriptor
{
Issuer = configuration.Issuer,
Audience = configuration.Audience,
IssuedAt = now.UtcDateTime,
NotBefore = now.UtcDateTime,
Expires = now.AddSeconds(configuration.TicketTtlSeconds).UtcDateTime,
Claims = claims,
SigningCredentials = signingCredentials,
};
var token = tokenHandler.CreateToken(descriptor);
return new StreamTicket(token, configuration.TicketTtlSeconds);
}
public void Dispose() => rsa.Dispose();
}
}