Merge remote-tracking branch 'origin/march-2023-03-21' into fix/2023-room-instances-publish-permissions

2026-10-25 23:18:44 -07:00 · 2026-10-25 11:59:05 +02:00
parent bf0f09ce84 0a3bad7c6c
commit 78c64d117a
19 changed files with 844 additions and 110 deletions
@@ -0,0 +1,97 @@
+using System.Net.Http.Headers;
+using System.Text.Json.Nodes;
+
+namespace DorkNet.Server.Services;
+
+/// <summary>
+/// Reads the client builds CI publishes (<c>ci/downloads/publish.py</c>): a
+/// <c>manifest.json</c> plus the files it lists, in a bucket served over plain
+/// HTTP (e.g. Garage's web endpoint on the internal network). The site's
+/// Downloads and Quest pages fetch them through the server, so the bucket
+/// itself never has to be reachable from outside.
+///
+/// Configured with <c>DorkNet:Downloads:BaseUrl</c> (the folder holding
+/// <c>manifest.json</c>) and optionally <c>DorkNet:Downloads:Host</c> (the
+/// Host header to send, for web endpoints that pick the bucket by host name).
+/// Without a base URL <see cref="IsConfigured"/> is false and the site hides
+/// both features.
+/// </summary>
+public sealed class DownloadsService
+{
+    public const string HttpClientName = "downloads";
+
+    // How long the bucket may take to start answering. The body then streams
+    // with no limit (the client has none; the caller's abort token ends it).
+    private static readonly TimeSpan HeaderTimeout = TimeSpan.FromSeconds(30);
+
+    private readonly IHttpClientFactory _httpClientFactory;
+    private readonly Uri? _baseUri;
+    private readonly string? _host;
+
+    public DownloadsService(IConfiguration config, IHttpClientFactory httpClientFactory, ILogger<DownloadsService> log)
+    {
+        _httpClientFactory = httpClientFactory;
+        var baseUrl = config["DorkNet:Downloads:BaseUrl"]?.Trim();
+        if (!string.IsNullOrEmpty(baseUrl) && Uri.TryCreate(baseUrl.TrimEnd('/') + "/", UriKind.Absolute, out var uri)
+            && (uri.Scheme == Uri.UriSchemeHttp || uri.Scheme == Uri.UriSchemeHttps))
+        {
+            _baseUri = uri;
+        }
+        var host = config["DorkNet:Downloads:Host"]?.Trim();
+        _host = string.IsNullOrEmpty(host) ? null : host;
+
+        if (_baseUri is null)
+            log.LogInformation("[downloads] no DorkNet:Downloads:BaseUrl; the Downloads page and Quest latest-build install are off");
+        else
+            log.LogInformation("[downloads] reading builds from {BaseUrl}{Host}", _baseUri, _host is null ? "" : $" (Host: {_host})");
+    }
+
+    public bool IsConfigured => _baseUri is not null;
+
+    /// <summary>The published manifest, or null when none has been published yet.</summary>
+    public async Task<JsonObject?> GetManifestAsync(CancellationToken ct)
+    {
+        using var res = await SendAsync("manifest.json", range: null, ct);
+        if (res.StatusCode == System.Net.HttpStatusCode.NotFound) return null;
+        res.EnsureSuccessStatusCode();
+        return JsonNode.Parse(await res.Content.ReadAsStringAsync(ct)) as JsonObject;
+    }
+
+    /// <summary>A manifest entry by its bucket path, or null when the manifest
+    /// doesn't list it. Only listed files are ever served.</summary>
+    public static JsonObject? FindFile(JsonObject manifest, string path)
+    {
+        if (manifest["releases"] is not JsonArray releases) return null;
+        return releases.OfType<JsonObject>()
+            .SelectMany(r => r["files"] is JsonArray files ? files.OfType<JsonObject>() : [])
+            .FirstOrDefault(f => string.Equals((string?)f["path"], path, StringComparison.Ordinal));
+    }
+
+    /// <summary>GET a file, forwarding the caller's Range header. The caller
+    /// owns the response and streams its content.</summary>
+    public Task<HttpResponseMessage> GetFileAsync(string path, string? range, CancellationToken ct)
+        => SendAsync(path, range, ct);
+
+    private async Task<HttpResponseMessage> SendAsync(string path, string? range, CancellationToken ct)
+    {
+        if (_baseUri is null) throw new InvalidOperationException("Downloads are not configured.");
+        var url = new Uri(_baseUri, string.Join('/', path.Split('/').Select(Uri.EscapeDataString)));
+        using var req = new HttpRequestMessage(HttpMethod.Get, url);
+        if (_host is not null) req.Headers.Host = _host;
+        if (!string.IsNullOrEmpty(range) && RangeHeaderValue.TryParse(range, out var r)) req.Headers.Range = r;
+        var client = _httpClientFactory.CreateClient(HttpClientName);
+        // The timeout covers only getting the headers: with ResponseHeadersRead
+        // the token is released once they arrive, and disposing the source
+        // here stops its timer before the body is streamed.
+        using var headers = CancellationTokenSource.CreateLinkedTokenSource(ct);
+        headers.CancelAfter(HeaderTimeout);
+        try
+        {
+            return await client.SendAsync(req, HttpCompletionOption.ResponseHeadersRead, headers.Token);
+        }
+        catch (OperationCanceledException) when (!ct.IsCancellationRequested)
+        {
+            throw new TimeoutException($"The downloads bucket didn't answer within {HeaderTimeout.TotalSeconds:0} s.");
+        }
+    }
+}