Initial WebhookServer implementation

Add the .NET 8 solution scaffolded against PLAN.md. Three projects share
WebhookServer.Core (models, auth, execution, storage, IPC, callbacks)
and WebhookServer.Service hosts an embedded Kestrel listener plus the
named-pipe admin server. WebhookServer.Gui is a thin MVVM client over
the pipe. Includes 25 unit tests covering HMAC verification, bearer
auth, IP allowlist parsing, arg-template rendering, DPAPI round-trip,
and the encrypt-on-save config store.

Install/uninstall PowerShell scripts default to LocalSystem and accept
a domain user or gMSA via -ServiceAccount.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-05-07 22:04:52 -04:00
parent 2f61b342af
commit 8ecfe84540
62 changed files with 3721 additions and 0 deletions
@@ -0,0 +1,219 @@
using System.Net;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using System.Threading.Channels;
using Microsoft.Extensions.Logging;
using WebhookServer.Core.Auth;
using WebhookServer.Core.Models;
using WebhookServer.Core.Storage;
namespace WebhookServer.Core.Callbacks;
/// <summary>
/// Bounded queue of pending callback deliveries with retry + backoff. Reuses
/// <see cref="HmacVerifier.Compute"/> so outbound HMAC matches the inbound code path.
///
/// Run <see cref="RunAsync"/> from a single long-running task (BackgroundService in the
/// service host); call <see cref="Enqueue"/> from anywhere. Disposing the dispatcher
/// disposes its <see cref="HttpClient"/>.
/// </summary>
public sealed class CallbackDispatcher : IDisposable
{
private const int QueueCapacity = 1024;
private static readonly TimeSpan MaxRetryAfter = TimeSpan.FromSeconds(60);
private readonly Channel<CallbackEnvelope> _channel;
private readonly HttpClient _http;
private readonly ILogger<CallbackDispatcher>? _logger;
public CallbackDispatcher(ILogger<CallbackDispatcher>? logger = null, HttpClient? httpClient = null)
{
_logger = logger;
_channel = Channel.CreateBounded<CallbackEnvelope>(new BoundedChannelOptions(QueueCapacity)
{
FullMode = BoundedChannelFullMode.DropOldest,
SingleReader = true,
SingleWriter = false,
});
_http = httpClient ?? new HttpClient(new SocketsHttpHandler
{
AllowAutoRedirect = true,
MaxAutomaticRedirections = 3,
});
}
public bool Enqueue(CallbackEnvelope envelope)
{
var ok = _channel.Writer.TryWrite(envelope);
if (!ok)
{
_logger?.LogWarning("Callback queue full; dropped envelope for endpoint {Slug}", envelope.EndpointSlug);
}
return ok;
}
public async Task RunAsync(CancellationToken stoppingToken)
{
await foreach (var envelope in _channel.Reader.ReadAllAsync(stoppingToken).ConfigureAwait(false))
{
try
{
await DeliverAsync(envelope, stoppingToken).ConfigureAwait(false);
}
catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
{
break;
}
catch (Exception ex)
{
_logger?.LogError(ex, "Unhandled error in callback dispatcher for {Slug}", envelope.EndpointSlug);
}
}
}
private async Task DeliverAsync(CallbackEnvelope envelope, CancellationToken stoppingToken)
{
var cfg = envelope.Config;
var maxAttempts = Math.Max(1, cfg.MaxAttempts);
var bodyBytes = SerializePayload(envelope.Payload, cfg);
for (int attempt = 1; attempt <= maxAttempts; attempt++)
{
using var attemptCts = CancellationTokenSource.CreateLinkedTokenSource(stoppingToken);
attemptCts.CancelAfter(TimeSpan.FromSeconds(Math.Max(1, cfg.TimeoutSeconds)));
var sw = System.Diagnostics.Stopwatch.StartNew();
HttpResponseMessage? response = null;
string? errorReason = null;
try
{
using var request = BuildRequest(envelope, bodyBytes);
response = await _http.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, attemptCts.Token).ConfigureAwait(false);
}
catch (TaskCanceledException) when (attemptCts.IsCancellationRequested && !stoppingToken.IsCancellationRequested)
{
errorReason = "timeout";
}
catch (Exception ex)
{
errorReason = ex.GetType().Name;
}
sw.Stop();
int? statusCode = (int?)response?.StatusCode;
bool delivered = response is { IsSuccessStatusCode: true };
_logger?.LogInformation(
"Callback {Slug} attempt {Attempt}/{Max} -> {Status} ({Latency} ms){Error}",
envelope.EndpointSlug, attempt, maxAttempts,
statusCode?.ToString() ?? "ERR",
sw.ElapsedMilliseconds,
errorReason is null ? "" : $" [{errorReason}]");
if (delivered)
{
response?.Dispose();
return;
}
var transient = errorReason is not null || (statusCode.HasValue && IsRetryable(statusCode.Value));
if (!transient || attempt == maxAttempts)
{
_logger?.LogWarning("Callback {Slug} {Disposition} after {Attempts} attempts",
envelope.EndpointSlug,
transient ? "gave-up" : "dropped",
attempt);
response?.Dispose();
return;
}
var delay = ComputeBackoff(attempt, response);
response?.Dispose();
try { await Task.Delay(delay, stoppingToken).ConfigureAwait(false); }
catch (OperationCanceledException) { return; }
}
}
private HttpRequestMessage BuildRequest(CallbackEnvelope envelope, byte[] bodyBytes)
{
var cfg = envelope.Config;
var method = cfg.Method == CallbackHttpMethod.Put ? HttpMethod.Put : HttpMethod.Post;
var request = new HttpRequestMessage(method, cfg.Url)
{
Content = new ByteArrayContent(bodyBytes),
};
request.Content.Headers.ContentType = new MediaTypeHeaderValue("application/json") { CharSet = "utf-8" };
switch (cfg.AuthMode)
{
case AuthMode.Bearer:
if (cfg.Bearer?.Secret.Plaintext is { Length: > 0 } token)
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
break;
case AuthMode.Hmac:
if (cfg.Hmac is { } hmac && hmac.Secret.Plaintext is { Length: > 0 } secret)
{
var sig = HmacVerifier.Compute(bodyBytes, secret, hmac.Algorithm, hmac.Encoding);
request.Headers.TryAddWithoutValidation(hmac.HeaderName, hmac.Prefix + sig);
}
break;
}
return request;
}
private static byte[] SerializePayload(CallbackPayload payload, CallbackConfig cfg)
{
// Honor the IncludeStdout / IncludeStderr flags by wiping them out before serialization.
var effective = new CallbackPayload
{
RunId = payload.RunId,
Endpoint = payload.Endpoint,
StartedAt = payload.StartedAt,
CompletedAt = payload.CompletedAt,
DurationMs = payload.DurationMs,
ExitCode = payload.ExitCode,
Succeeded = payload.Succeeded,
TimedOut = payload.TimedOut,
Stdout = cfg.IncludeStdout ? payload.Stdout : null,
Stderr = cfg.IncludeStderr ? payload.Stderr : null,
StdoutTruncated = cfg.IncludeStdout && payload.StdoutTruncated,
StderrTruncated = cfg.IncludeStderr && payload.StderrTruncated,
};
return JsonSerializer.SerializeToUtf8Bytes(effective, ConfigJson.Compact);
}
private static bool IsRetryable(int status) => status switch
{
408 or 425 or 429 => true,
>= 500 and <= 599 => true,
_ => false,
};
private static TimeSpan ComputeBackoff(int attempt, HttpResponseMessage? response)
{
if (response?.Headers.RetryAfter is { } ra)
{
if (ra.Delta.HasValue)
return Min(ra.Delta.Value, MaxRetryAfter);
if (ra.Date.HasValue)
{
var delta = ra.Date.Value - DateTimeOffset.UtcNow;
if (delta > TimeSpan.Zero) return Min(delta, MaxRetryAfter);
}
}
// Exponential: 1s, 2s, 4s, 8s, 16s, 32s, 60s cap
var seconds = Math.Min(60, Math.Pow(2, attempt - 1));
var jitter = (Random.Shared.NextDouble() * 0.5) - 0.25; // ±25%
return TimeSpan.FromSeconds(seconds * (1 + jitter));
}
private static TimeSpan Min(TimeSpan a, TimeSpan b) => a < b ? a : b;
public void Dispose() => _http.Dispose();
}
@@ -0,0 +1,15 @@
using WebhookServer.Core.Models;
namespace WebhookServer.Core.Callbacks;
/// <summary>
/// Internal queue item pairing a payload with the resolved <see cref="CallbackConfig"/>
/// for the endpoint. The dispatcher reads from a channel of these.
/// </summary>
public sealed class CallbackEnvelope
{
public required Guid EndpointId { get; init; }
public required string EndpointSlug { get; init; }
public required CallbackConfig Config { get; init; }
public required CallbackPayload Payload { get; init; }
}
@@ -0,0 +1,22 @@
using System.Text.Json.Serialization;
namespace WebhookServer.Core.Callbacks;
/// <summary>
/// JSON body POSTed to a configured outbound callback URL.
/// </summary>
public sealed class CallbackPayload
{
[JsonPropertyName("runId")] public required string RunId { get; init; }
[JsonPropertyName("endpoint")] public required string Endpoint { get; init; }
[JsonPropertyName("startedAt")] public required DateTimeOffset StartedAt { get; init; }
[JsonPropertyName("completedAt")] public required DateTimeOffset CompletedAt { get; init; }
[JsonPropertyName("durationMs")] public required long DurationMs { get; init; }
[JsonPropertyName("exitCode")] public required int ExitCode { get; init; }
[JsonPropertyName("succeeded")] public required bool Succeeded { get; init; }
[JsonPropertyName("timedOut")] public required bool TimedOut { get; init; }
[JsonPropertyName("stdout")] public string? Stdout { get; init; }
[JsonPropertyName("stderr")] public string? Stderr { get; init; }
[JsonPropertyName("stdoutTruncated")] public bool StdoutTruncated { get; init; }
[JsonPropertyName("stderrTruncated")] public bool StderrTruncated { get; init; }
}