ISC.Kafka.Extensions.Publisher 1.0.0

ISC.Kafka.Extensions.Publisher

ISC.Kafka.Extensions.Publisher is a lightweight .NET package for publishing messages to Kafka.

It provides two main integration flows:

1. Structured logging flow with IElasticLogger (log model is built and serialized automatically).
2. Raw message publishing flow with IKafkaPublisher (full control over your payload).

Requirements

• .NET 8+
• A reachable Kafka cluster
• Topic(s) created in Kafka

Flow 1: Use IElasticLogger for structured log publishing

Use this flow when you want to publish logs in a standard model (LoggerModel<T>) with:

• CreateDate
• LogLevel
• HttpStatus
• Url
• Method
• RequestBody
• Resource (ServiceName)
• ClientId (resolved from HttpContext.Items[Global.RESOURCE])

1) Configure options

using ISC.Kafka.Extensions.Publisher.Logging;

var loggerOptions = new ElasticLoggerModelOption
{
    BootstrapServers = "localhost:9092",
    Topic = "app-logs",
    Username = "",
    Password = "",
    ServiceName = "OrderService"
};

2) Create logger instance

IElasticLogger elasticLogger = new ElasticLogger(loggerOptions);

3) Publish logs

elasticLogger.Information(
    message: "Create order success",
    requestBody: "{\"orderId\":\"ORD-001\"}",
    httpStatus: 200,
    url: "/api/orders",
    method: "POST");

await elasticLogger.ErrorAsync(
    message: "Create order failed",
    requestBody: "{\"orderId\":\"ORD-002\"}",
    httpStatus: 500,
    url: "/api/orders",
    method: "POST");

4) Set per-request client id (ASP.NET Core)

ElasticLogger reads ClientId from:

HttpContext.Items[Global.RESOURCE]

Example middleware:

using ISC.Kafka.Extensions.Publisher.SeedWork;

app.Use(async (context, next) =>
{
    context.Items[Global.RESOURCE] = context.Request.Headers["x-client-id"].ToString();
    await next();
});

Flow 2: Use IKafkaPublisher for raw message publishing

Use this flow when you want direct control over message content and key.

1) Create publisher

using ISC.Kafka.Extensions.Publisher;

IKafkaPublisher publisher = new KafkaPublisher(
    bootstrapServers: "localhost:9092",
    topic: "order-events",
    username: "",
    password: "");

2) Publish with PubMessageCustomAsync

var payload = new
{
    EventName = "OrderCreated",
    OrderId = "ORD-1001",
    CreatedAt = DateTime.UtcNow
};

var message = System.Text.Json.JsonSerializer.Serialize(payload);
await publisher.PubMessageCustomAsync(message, messageKey: "ORD-1001");

Notes

• Prefer async APIs (ErrorAsync, InformationAsync, PubMessageCustomAsync) for non-blocking I/O.
• ElasticLogger truncates very large requestBody values to avoid oversized Kafka messages.
• Ensure the target topic and broker security settings match your environment.