From 947bf35cf690488fc0f3cc4d0c657d7529f20c3a Mon Sep 17 00:00:00 2001
From: watsonb8 <b.watson@watsonlabs.net>
Date: Fri, 14 Jun 2024 09:48:52 -0500
Subject: [PATCH] Working communication via kafka

---
 consumer/Consumer.cs                  | 52 +++++++++++++++++++++++++++
 consumer/Model/DataModel.cs           | 18 ++++++++++
 consumer/Program.cs                   |  2 --
 consumer/Serializer/JsonSerializer.cs | 22 ++++++++++++
 producer/Producer.cs                  |  8 +++--
 producer/Serializer/JsonSerializer.cs | 22 ++++++++++++
 6 files changed, 120 insertions(+), 4 deletions(-)
 create mode 100644 consumer/Consumer.cs
 create mode 100644 consumer/Model/DataModel.cs
 delete mode 100644 consumer/Program.cs
 create mode 100644 consumer/Serializer/JsonSerializer.cs
 create mode 100644 producer/Serializer/JsonSerializer.cs

diff --git a/consumer/Consumer.cs b/consumer/Consumer.cs
new file mode 100644
index 0000000..c478b9b
--- /dev/null
+++ b/consumer/Consumer.cs
@@ -0,0 +1,52 @@
+using System;
+using System.Threading;
+using Confluent.Kafka;
+using Model;
+using Serializers;
+
+class Consumer
+{
+    public static void Main(string[] args)
+    {
+        var conf = new ConsumerConfig{
+            GroupId = "test-consumer-group",
+            BootstrapServers = "localhost:29092",
+            AutoOffsetReset = AutoOffsetReset.Latest
+        };
+
+        using (var consumer = new ConsumerBuilder<Ignore, DataModel>(conf)
+            .SetValueDeserializer(new JsonSerializer<DataModel>())
+            .Build())
+        {
+            consumer.Subscribe("test-topic");
+
+            CancellationTokenSource cts = new CancellationTokenSource();
+            Console.CancelKeyPress += (_, e) => {
+                e.Cancel = true;
+                cts.Cancel();
+            };
+
+            try
+            {
+                while(true)
+                {
+                    try
+                    {
+                        var cr = consumer.Consume(cts.Token);
+            
+                        Console.WriteLine($"Consumed message with id '{cr.Message.Value.id}' at: '{cr.TopicPartitionOffset}'.");
+                    }
+                    catch (ConsumeException e)
+                    {
+                        Console.WriteLine($"Error occured: {e.Error.Reason}");
+                    }
+                }
+            }
+            catch (OperationCanceledException)
+            {
+                // Ensure the consumer leaves the group cleanly and final offsets are committed.
+                consumer.Close();
+            }
+        }
+    }
+}
diff --git a/consumer/Model/DataModel.cs b/consumer/Model/DataModel.cs
new file mode 100644
index 0000000..7e473f3
--- /dev/null
+++ b/consumer/Model/DataModel.cs
@@ -0,0 +1,18 @@
+namespace Model
+{
+    public class DataModel 
+    {
+        public DataModel(string id)
+        {
+            this.id = id;
+        }
+
+        public string id { get; set; }
+
+        public string? name { get; set; }
+
+        public string? description { get; set; }
+
+        public string? notes { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/consumer/Program.cs b/consumer/Program.cs
deleted file mode 100644
index 3751555..0000000
--- a/consumer/Program.cs
+++ /dev/null
@@ -1,2 +0,0 @@
-// See https://aka.ms/new-console-template for more information
-Console.WriteLine("Hello, World!");
diff --git a/consumer/Serializer/JsonSerializer.cs b/consumer/Serializer/JsonSerializer.cs
new file mode 100644
index 0000000..f2ac15c
--- /dev/null
+++ b/consumer/Serializer/JsonSerializer.cs
@@ -0,0 +1,22 @@
+using Confluent.Kafka;
+using System.Text.Json;
+
+namespace Serializers
+{
+    public class JsonSerializer<T> : ISerializer<T>, IDeserializer<T>
+    {
+        public byte[] Serialize(T data, SerializationContext context)
+        {
+            return JsonSerializer.SerializeToUtf8Bytes(data);
+        }
+
+        public T Deserialize(ReadOnlySpan<byte> data, bool isNull, SerializationContext context)
+        {
+            if (!isNull)
+            {
+                return JsonSerializer.Deserialize<T>(data);
+            }
+            throw new Exception ("Data cannot be null");
+        }
+    }
+}
\ No newline at end of file
diff --git a/producer/Producer.cs b/producer/Producer.cs
index 910efbd..ba4c9e8 100644
--- a/producer/Producer.cs
+++ b/producer/Producer.cs
@@ -1,15 +1,19 @@
 using System;
+using System.Text.Json;
 using System.Threading.Tasks;
 using Confluent.Kafka;
+using Serializers;
 using Model;
 
 class Producer
 {
     public static async Task Main (string[] args)
     {
-        var config = new ProducerConfig { BootstrapServers = "localhost:9092" };
+        var config = new ProducerConfig { BootstrapServers = "localhost:29092" };
 
-        using (var producerBuilder = new ProducerBuilder<string, DataModel>(config).Build())
+        using (var producerBuilder = new ProducerBuilder<string, DataModel>(config)
+            .SetValueSerializer(new JsonSerializer<DataModel>())
+            .Build())
         {
             try
             {
diff --git a/producer/Serializer/JsonSerializer.cs b/producer/Serializer/JsonSerializer.cs
new file mode 100644
index 0000000..f2ac15c
--- /dev/null
+++ b/producer/Serializer/JsonSerializer.cs
@@ -0,0 +1,22 @@
+using Confluent.Kafka;
+using System.Text.Json;
+
+namespace Serializers
+{
+    public class JsonSerializer<T> : ISerializer<T>, IDeserializer<T>
+    {
+        public byte[] Serialize(T data, SerializationContext context)
+        {
+            return JsonSerializer.SerializeToUtf8Bytes(data);
+        }
+
+        public T Deserialize(ReadOnlySpan<byte> data, bool isNull, SerializationContext context)
+        {
+            if (!isNull)
+            {
+                return JsonSerializer.Deserialize<T>(data);
+            }
+            throw new Exception ("Data cannot be null");
+        }
+    }
+}
\ No newline at end of file