Add health check endpoint for the .NET API

CHANGELOG.md

@@ -7,6 +7,7 @@
 - Tooltips to main side navigation.
 - Location hash for tabs in borehole detail view.
 - Language dropdown in the header.
+- Added health check endpoint for the .NET API.
 
 ### Changed
 

src/api/BDMS.csproj

@@ -25,6 +25,7 @@
     <PackageReference Include="Humanizer" Version="2.14.1" />
     <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="8.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Versioning" Version="5.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Diagnostics.HealthChecks.EntityFrameworkCore" Version="8.0.0" />
     <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="8.0.0" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="8.0.0" />
     <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL.NetTopologySuite" Version="8.0.0" />

src/api/Dockerfile

@@ -51,7 +51,7 @@ ENV LC_ALL=C.UTF-8
 
 COPY --from=build /app/publish .
 
-HEALTHCHECK CMD curl --fail http://localhost:8080/ || exit 1
+HEALTHCHECK CMD curl --fail http://localhost:8080/health || exit 1
 
 # Switch to the non-root user 'app' defined in the base image
 USER $APP_UID

src/api/Program.cs

@@ -54,7 +54,7 @@
 builder.Services.AddHttpContextAccessor();
 builder.Services.AddHttpClient();
 
-var connectionString = builder.Configuration.GetConnectionString("BdmsContext");
+var connectionString = builder.Configuration.GetConnectionString(nameof(BdmsContext));
 builder.Services.AddNpgsql<BdmsContext>(connectionString, options =>
 {
     options.UseQuerySplittingBehavior(QuerySplittingBehavior.SplitQuery);
@@ -73,7 +73,7 @@
     options.SwaggerDoc("v2", new OpenApiInfo
     {
         Version = "v2",
-        Title = "BDMS REST API v2",
+        Title = "Boreholes REST API v2",
     });
     options.AddSecurityDefinition("OpenIdConnect", new OpenApiSecurityScheme
     {
@@ -139,6 +139,11 @@
 builder.Services.AddScoped<IBoreholeLockService, BoreholeLockService>();
 builder.Services.AddSingleton(TimeProvider.System);
 
+builder.Services
+    .AddHealthChecks()
+    .AddDbContextCheck<BdmsContext>("Database")
+    .AddCheck<S3HealthCheck>("S3");
+
 var app = builder.Build();
 
 // Migrate db changes on startup
@@ -166,5 +171,6 @@
 
 app.MapControllers();
 app.MapReverseProxy();
+app.MapHealthChecks("/health").AllowAnonymous();
 
 app.Run();

src/api/S3HealthCheck.cs

@@ -0,0 +1,38 @@
+using Amazon.S3;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+using System.Net;
+
+namespace BDMS;
+
+public class S3HealthCheck : IHealthCheck
+{
+    private readonly IAmazonS3 s3Client;
+
+    /// <summary>
+    /// Creates a new instance of <see cref="S3HealthCheck"/>.
+    /// </summary>
+    /// <param name="s3Client">The <see cref="IAmazonS3"/> client.</param>
+    /// <param name="configuration">The <see cref="IConfiguration"/> object.</param>
+    public S3HealthCheck(IAmazonS3 s3Client, IConfiguration configuration) => this.s3Client = s3Client;
+
+    /// <inheritdoc />
+    public async Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
+    {
+        var healthCheckResult = HealthCheckResult.Healthy();
+
+        try
+        {
+            var response = await s3Client.ListBucketsAsync(cancellationToken).ConfigureAwait(false);
+            if (response.HttpStatusCode != HttpStatusCode.OK)
+            {
+                healthCheckResult = HealthCheckResult.Unhealthy();
+            }
+        }
+        catch (Exception)
+        {
+            healthCheckResult = HealthCheckResult.Unhealthy();
+        }
+
+        return await Task.FromResult(healthCheckResult).ConfigureAwait(false);
+    }
+}