Feat/issue #12 detect kafka changes

CHANGELOG.md

@@ -1,3 +1,8 @@
+## v1.4.0 (December 17, 2024)
+
+### Added:
+- `ReloadOnChange` flag to Kafka configuration. This allows you to change the configuration without restarting the application.
+
 ## v1.3.0 (October 26, 2024)
 
 ### Changed:

README.md

@@ -119,6 +119,7 @@ set:
 
 | **Key**                                      | **Type** | **Description**                                                                                                                                                    |
 |----------------------------------------------|----------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `Kafka.ReloadOnChange`                         | bool     | The flag indicating whether the Kafka configuration should be reloaded when the configuration file changes.                                                        |
 | `Kafka.SaslUsername`                         | string   | The username for the SASL authentication of the Kafka cluster.                                                                                                     |
 | `Kafka.Brokers`                              | string   | The addresses of the Kafka brokers.                                                                                                                                |
 | `Kafka.SaslPassword`                         | string   | The password for the SASL authentication of the Kafka cluster.                                                                                                     |

example/Couchbase/config/config.json

@@ -19,6 +19,7 @@
     ]
   },
   "Kafka": {
+    "reloadOnChange": true,
     "SaslUsername": "",
     "Brokers": "",
     "SslCaLocation": "",

example/MsSql/config/config.json

@@ -19,6 +19,7 @@
     ]
   },
   "Kafka": {
+    "reloadOnChange": true,
     "SaslUsername": "",
     "Brokers": "",
     "SslCaLocation": "",

example/Postgres/config/config.json

@@ -19,6 +19,7 @@
     ]
   },
   "Kafka": {
+    "reloadOnChange": true,
     "SaslUsername": "",
     "Brokers": "",
     "SslCaLocation": "",

src/ConfigOptions/Kafka.cs

@@ -19,4 +19,5 @@ public class Kafka
     public Acks? Acks { get; set; }
     public double? LingerMs { get; set; }
     public string ClientId { get; set; }
+    public bool ReloadOnChange { get; set; }
 }

src/Coordinators/Services/KafkaProducer.cs

@@ -2,6 +2,7 @@
 using System.Diagnostics.CodeAnalysis;
 using System.Threading.Tasks;
 using Confluent.Kafka;
+using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using NewRelic.Api.Agent;
 using PollingOutboxPublisher.ConfigOptions;
@@ -13,13 +14,26 @@ namespace PollingOutboxPublisher.Coordinators.Services;
 public sealed class KafkaProducer : IKafkaProducer
 {
     private IProducer<string, string> _producer;
+    private Kafka _kafkaConfiguration;
+    private readonly ILogger<KafkaProducer> _logger;
 
-    public KafkaProducer(IOptions<Kafka> kafkaOptions)
+    public KafkaProducer(IOptionsMonitor<Kafka> kafkaOptionsMonitor, ILogger<KafkaProducer> logger)
     {
-        var kafkaConfiguration = kafkaOptions.Value;
-        BuildProducer(kafkaConfiguration);
+        _logger = logger;
+        _kafkaConfiguration = kafkaOptionsMonitor.CurrentValue;
+        kafkaOptionsMonitor.OnChange(OnKafkaConfigChanged);
+        BuildProducer(_kafkaConfiguration);
     }
 
+    private void OnKafkaConfigChanged(Kafka newKafkaConfig)
+    {
+        if (!newKafkaConfig.ReloadOnChange) return;
+
+        _logger.LogInformation("Kafka configuration changed");
+        _kafkaConfiguration = newKafkaConfig;
+        BuildProducer(_kafkaConfiguration);
+    }
+
     private void BuildProducer(Kafka kafka)
     {
         var config = new ProducerConfig
@@ -38,6 +52,12 @@ private void BuildProducer(Kafka kafka)
             MessageMaxBytes = kafka.MessageMaxBytes ?? 30000000,
             Acks = kafka.Acks ?? Acks.Leader
         };
+
+        if (_producer != null)
+        {
+            _producer.Flush(TimeSpan.FromSeconds(10));
+            _producer.Dispose();
+        }
         _producer = new ProducerBuilder<string, string>(config).Build();
     }
 

src/PollingOutboxPublisher.csproj

@@ -4,7 +4,7 @@
         <OutputType>Exe</OutputType>
         <TargetFramework>net8.0</TargetFramework>
         <IsPackable>false</IsPackable>
-        <Version>1.3.0</Version>
+        <Version>1.4.0</Version>
         <RootNamespace>PollingOutboxPublisher</RootNamespace>
     </PropertyGroup>
 

src/Program.cs

@@ -31,33 +31,20 @@ public static class Program
 {
     public static async Task Main(string[] args)
     {
-        CheckConfigFileExistence();
         var host = CreateHostBuilder(args).Build();
-
         //ExampleRunner.RunPostgresExample(host);
-
         await host.RunAsync();
     }
-
-    private static void CheckConfigFileExistence()
-    {
-        var isConfigExist = File.Exists(Directory.GetCurrentDirectory() + "/config/config.json");
-        if (!isConfigExist)
-            throw new FileNotFoundException("File not found", "config.json");
-
-        var isSecretExist = File.Exists(Directory.GetCurrentDirectory() + "/config/secret.json");
-        if (!isSecretExist)
-            throw new FileNotFoundException("File not found", "secret.json");
-    }
-
+
     private static IHostBuilder CreateHostBuilder(string[] args)
     {
         return Host.CreateDefaultBuilder(args)
             .ConfigureAppConfiguration(
                 (_, builder) =>
                 {
-                    builder.AddJsonFile("config/config.json", true, true)
-                        .AddJsonFile("config/secret.json", true, true)
+                    builder
+                        .AddJsonFile("config/config.json", false, true)
+                        .AddJsonFile("config/secret.json", false, true)
                         .Build();
                 })
             .ConfigureServices((hostContext, services) =>