Add otel metrics for Npgsql

Author: johnsimons

src/Directory.Packages.props

@@ -34,6 +34,7 @@
     <PackageVersion Include="Mindscape.Raygun4Net.NetCore" Version="11.2.1" />
     <PackageVersion Include="NLog.Extensions.Logging" Version="5.4.0" />
     <PackageVersion Include="Npgsql" Version="9.0.3" />
+    <PackageVersion Include="Npgsql.OpenTelemetry" Version="9.0.3" />
     <PackageVersion Include="NServiceBus" Version="9.2.7" />
     <PackageVersion Include="NServiceBus.AcceptanceTesting" Version="9.2.7" />
     <PackageVersion Include="NServiceBus.AmazonSQS" Version="8.0.0" />

src/ServiceControl.Audit.Persistence.PostgreSQL/PostgreSQLPersistence.cs

@@ -1,11 +1,14 @@
 namespace ServiceControl.Audit.Persistence.PostgreSQL;
 
 using Microsoft.Extensions.DependencyInjection;
+using OpenTelemetry.Metrics;
 using ServiceControl.Audit.Auditing.BodyStorage;
 using ServiceControl.Audit.Persistence;
 using ServiceControl.Audit.Persistence.PostgreSQL.BodyStorage;
 using ServiceControl.Audit.Persistence.PostgreSQL.UnitOfWork;
 using ServiceControl.Audit.Persistence.UnitOfWork;
+using Npgsql;
+
 class PostgreSQLPersistence(DatabaseConfiguration databaseConfiguration) : IPersistence
 {
     public void AddInstaller(IServiceCollection services)
@@ -24,5 +27,6 @@ public void AddPersistence(IServiceCollection services)
         services.AddSingleton<IBodyStorage, PostgreSQLAttachmentsBodyStorage>();
         services.AddSingleton<PostgreSQLConnectionFactory>();
         services.AddHostedService<RetentionCleanupService>();
+        services.ConfigureOpenTelemetryMeterProvider(b => b.AddNpgsqlInstrumentation());
     }
 }

src/ServiceControl.Audit.Persistence.PostgreSQL/RetentionCleanupService.cs

@@ -22,23 +22,21 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
             {
                 await Task.Delay(TimeSpan.FromSeconds(config.ExpirationProcessTimerInSeconds), stoppingToken);
 
-                await CleanupOldMessagesAsync(stoppingToken);
+                await CleanupOldMessages(stoppingToken);
             }
-            catch (OperationCanceledException)
+            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
             {
-                // Expected when shutting down
+                logger.LogInformation($"{nameof(RetentionCleanupService)} stopped.");
                 break;
             }
             catch (Exception ex)
             {
                 logger.LogError(ex, "Error during cleanup task.");
             }
         }
-
-        logger.LogInformation($"{nameof(RetentionCleanupService)} stopped.");
     }
 
-    async Task CleanupOldMessagesAsync(CancellationToken cancellationToken)
+    async Task CleanupOldMessages(CancellationToken cancellationToken)
     {
         await using var conn = await connectionFactory.OpenConnection(cancellationToken);
 

src/ServiceControl.Audit.Persistence.PostgreSQL/ServiceControl.Audit.Persistence.PostgreSQL.csproj

@@ -25,6 +25,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.IO.RecyclableMemoryStream" />
     <PackageReference Include="Npgsql" />
+    <PackageReference Include="Npgsql.OpenTelemetry" />
   </ItemGroup>
 
 </Project>