Add healthchecks to the api

back/Dockerfile

@@ -23,11 +23,12 @@ ARG VERSION
 RUN dotnet publish --no-restore -c Release -o /app "-p:Version=${VERSION:-"0.0.0-dev"};SkipTranscoder=true" src/Kyoo.Host
 
 FROM mcr.microsoft.com/dotnet/aspnet:6.0
-RUN apt-get update && apt-get install -y libavutil-dev libavcodec-dev libavformat-dev
+RUN apt-get update && apt-get install -y libavutil-dev libavcodec-dev libavformat-dev curl
 COPY --from=builder /app /app
 COPY --from=transcoder /transcoder/libtranscoder.so /app
 
 WORKDIR /kyoo
 EXPOSE 5000
+HEALTHCHECK CMD curl --fail http://localhost:5000/health || exit
 CMD /app/Kyoo.Host
 

back/Dockerfile.dev

@@ -5,7 +5,7 @@ COPY src/Kyoo.Transcoder .
 RUN cmake . && make -j
 
 FROM mcr.microsoft.com/dotnet/sdk:6.0
-RUN apt-get update && apt-get install -y libavutil-dev libavcodec-dev libavformat-dev
+RUN apt-get update && apt-get install -y libavutil-dev libavcodec-dev libavformat-dev curl
 WORKDIR /app
 
 COPY Kyoo.sln ./Kyoo.sln
@@ -25,5 +25,6 @@ COPY --from=transcoder /transcoder/libtranscoder.so /app
 WORKDIR /kyoo
 EXPOSE 5000
 ENV DOTNET_USE_POLLING_FILE_WATCHER 1
+HEALTHCHECK CMD curl --fail http://localhost:5000/health || exit
 CMD dotnet watch run --no-restore --project /app/src/Kyoo.Host
 

back/src/Kyoo.Core/Views/Health.cs

@@ -0,0 +1,70 @@
+// Kyoo - A portable and vast media library solution.
+// Copyright (c) Kyoo.
+//
+// See AUTHORS.md and LICENSE file in the project root for full license information.
+//
+// Kyoo is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// any later version.
+//
+// Kyoo is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Kyoo. If not, see <https://www.gnu.org/licenses/>.
+
+using System.Threading.Tasks;
+using Kyoo.Abstractions.Models.Attributes;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace Kyoo.Core.Api
+{
+	/// <summary>
+	/// An API endpoint to check the health.
+	/// </summary>
+	[Route("health")]
+	[ApiController]
+	[ApiDefinition("Health")]
+	public class Health : BaseApi
+	{
+		private readonly HealthCheckService _healthCheckService;
+
+		/// <summary>
+		/// Create a new <see cref="Health"/>.
+		/// </summary>
+		/// <param name="healthCheckService">The service to check health.</param>
+		public Health(HealthCheckService healthCheckService)
+		{
+			_healthCheckService = healthCheckService;
+		}
+
+		/// <summary>
+		/// Check if the api is ready to accept requests.
+		/// </summary>
+		/// <returns>A status indicating the health of the api.</returns>
+		[HttpGet]
+		[ProducesResponseType(StatusCodes.Status204NoContent)]
+		[ProducesResponseType(StatusCodes.Status503ServiceUnavailable)]
+		public async Task<IActionResult> CheckHealth()
+		{
+			IHeaderDictionary headers = HttpContext.Response.Headers;
+			headers.CacheControl = "no-store, no-cache";
+			headers.Pragma = "no-cache";
+			headers.Expires = "Thu, 01 Jan 1970 00:00:00 GMT";
+
+			HealthReport result = await _healthCheckService.CheckHealthAsync();
+			return result.Status switch
+			{
+				HealthStatus.Healthy => NoContent(),
+				HealthStatus.Unhealthy => NoContent(),
+				HealthStatus.Degraded => StatusCode(StatusCodes.Status503ServiceUnavailable),
+				_ => StatusCode(StatusCodes.Status500InternalServerError),
+			};
+		}
+	}
+}

back/src/Kyoo.Host/Application.cs

@@ -24,6 +24,7 @@ using System.Threading.Tasks;
 using Autofac;
 using Autofac.Extensions.DependencyInjection;
 using Kyoo.Postgresql;
+using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;

back/src/Kyoo.Postgresql/Kyoo.Postgresql.csproj

@@ -10,6 +10,7 @@
 			<PrivateAssets>all</PrivateAssets>
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
 		</PackageReference>
+		<PackageReference Include="Microsoft.Extensions.Diagnostics.HealthChecks.EntityFrameworkCore" Version="5.0.7" />
 		<PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="5.0.7" />
 		<PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="5.0.8" />
 	</ItemGroup>

back/src/Kyoo.Postgresql/PostgresModule.cs

@@ -91,6 +91,8 @@ namespace Kyoo.Postgresql
 				if (_environment.IsDevelopment())
 					x.EnableDetailedErrors().EnableSensitiveDataLogging();
 			}, ServiceLifetime.Transient);
+
+			services.AddHealthChecks().AddDbContextCheck<DatabaseContext>();
 		}
 	}
 }