Add optional health checks to ASF API

ArchiSteamFarm/IPC/ArchiKestrel.cs

@@ -377,6 +377,9 @@ internal static class ArchiKestrel {
 			}
 		);
 
+		// Add support for optional healtchecks
+		services.AddHealthChecks();
+
 		// We need MVC for /Api, but we're going to use only a small subset of all available features
 		IMvcBuilder mvc = services.AddControllers();
 

ArchiSteamFarm/IPC/Controllers/Api/HealthCheckController.cs

@@ -0,0 +1,58 @@
+// ----------------------------------------------------------------------------------------------
+//     _                _      _  ____   _                           _____
+//    / \    _ __  ___ | |__  (_)/ ___| | |_  ___   __ _  _ __ ___  |  ___|__ _  _ __  _ __ ___
+//   / _ \  | '__|/ __|| '_ \ | |\___ \ | __|/ _ \ / _` || '_ ` _ \ | |_  / _` || '__|| '_ ` _ \
+//  / ___ \ | |  | (__ | | | || | ___) || |_|  __/| (_| || | | | | ||  _|| (_| || |   | | | | | |
+// /_/   \_\|_|   \___||_| |_||_||____/  \__|\___| \__,_||_| |_| |_||_|   \__,_||_|   |_| |_| |_|
+// ----------------------------------------------------------------------------------------------
+// |
+// Copyright 2015-2024 Łukasz "JustArchi" Domeradzki
+// Contact: JustArchi@JustArchi.net
+// |
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// |
+// http://www.apache.org/licenses/LICENSE-2.0
+// |
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+using System.Net;
+using System.Threading;
+using System.Threading.Tasks;
+using ArchiSteamFarm.IPC.Responses;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace ArchiSteamFarm.IPC.Controllers.Api;
+
+[ApiController]
+[Produces("application/json")]
+[Route("/HealthCheck")]
+public sealed class HealthCheckController : ControllerBase {
+	private readonly HealthCheckService HealthCheckService;
+
+	public HealthCheckController(HealthCheckService healthCheckService) {
+		ArgumentNullException.ThrowIfNull(healthCheckService);
+
+		HealthCheckService = healthCheckService;
+	}
+
+	[HttpGet]
+	[ProducesResponseType(typeof(HealthCheckResponse), (int) HttpStatusCode.OK)]
+	[ProducesResponseType(typeof(HealthCheckResponse), (int) HttpStatusCode.ServiceUnavailable)]
+	public async Task<IActionResult> Get() {
+		CancellationToken cancellationToken = HttpContext.RequestAborted;
+
+		HealthReport report = await HealthCheckService.CheckHealthAsync(cancellationToken).ConfigureAwait(false);
+
+		HealthCheckResponse response = new(report);
+
+		return report.Status == HealthStatus.Healthy ? Ok(response) : StatusCode((int) HttpStatusCode.ServiceUnavailable, response);
+	}
+}

ArchiSteamFarm/IPC/Responses/HealthCheckResponse.cs

@@ -0,0 +1,46 @@
+// ----------------------------------------------------------------------------------------------
+//     _                _      _  ____   _                           _____
+//    / \    _ __  ___ | |__  (_)/ ___| | |_  ___   __ _  _ __ ___  |  ___|__ _  _ __  _ __ ___
+//   / _ \  | '__|/ __|| '_ \ | |\___ \ | __|/ _ \ / _` || '_ ` _ \ | |_  / _` || '__|| '_ ` _ \
+//  / ___ \ | |  | (__ | | | || | ___) || |_|  __/| (_| || | | | | ||  _|| (_| || |   | | | | | |
+// /_/   \_\|_|   \___||_| |_||_||____/  \__|\___| \__,_||_| |_| |_||_|   \__,_||_|   |_| |_| |_|
+// ----------------------------------------------------------------------------------------------
+// |
+// Copyright 2015-2024 Łukasz "JustArchi" Domeradzki
+// Contact: JustArchi@JustArchi.net
+// |
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// |
+// http://www.apache.org/licenses/LICENSE-2.0
+// |
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+using System.ComponentModel.DataAnnotations;
+using System.Text.Json.Serialization;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace ArchiSteamFarm.IPC.Responses;
+
+public sealed class HealthCheckResponse {
+	[JsonInclude]
+	[Required]
+	public string StatusText => Status.ToString();
+
+	[JsonInclude]
+	[JsonRequired]
+	[Required]
+	public HealthStatus Status { get; private init; }
+
+	internal HealthCheckResponse(HealthReport report) {
+		ArgumentNullException.ThrowIfNull(report);
+
+		Status = report.Status;
+	}
+}