🖥️ Kafdrop — A Simple UI to See What's Happening in Kafka

Apache Kafka is powerful, but working with it can feel like flying blind.

You can send and receive messages — but how do you see what's going on?

That’s where Kafdrop comes in.

Kafdrop is a web-based UI for viewing Kafka topics, messages, consumers, and brokers — all in one place.

🔍 Why Use Kafdrop?

Here’s what Kafdrop helps you do:

• View all Kafka topics (and what's inside them)
• See consumer groups and their lag
• Browse messages in a topic
• Inspect brokers and partitions

In short, Kafdrop makes Kafka human-friendly 🧠

⚙️ How Kafdrop Works

Kafdrop connects to your Kafka cluster and exposes a clean web UI.

Here’s the setup:

• Kafka is already running (locally or on the cloud)
• You run Kafdrop as a Docker container or Java app
• It connects to your Kafka and shows all data

🚀 Run Kafdrop with Docker

Here’s how you can launch Kafdrop with Docker (the easiest way).

1. Start Kafka and Zookeeper (if not already running)

Use Docker Compose or your preferred method.

2. Run Kafdrop

docker run -d -p 9000:9000   -e KAFKA_BROKERCONNECT=localhost:9092   obsidiandynamics/kafdrop

Then open your browser and go to: http://localhost:9000

You’ll see a dashboard like this:

• ✅ List of Topics
• 📊 Partitions & Offsets
• 📦 Message Preview
• 👥 Consumer Groups & Lag

🧪 Example: View Pizza Orders in Kafdrop

If you’re running a Kafka topic called pizza-orders (from our previous blog), you can:

1. Open Kafdrop
2. Click on pizza-orders
3. Browse recent messages (e.g., "Order #42 - Pepperoni Pizza")
4. See which consumers have received it

It’s like opening a window into your Kafka system.

💡 Common Use Cases

• Debugging: See if producers are sending messages correctly
• Monitoring: Track consumer lag and topic size
• Learning: Understand how Kafka works with real-time visuals

📌 Quick Reference

🧰 Other Ways to Use Kafdrop

If you don’t want Docker, you can also:

Run via JAR file

java -jar kafdrop.jar   --kafka.brokerConnect=localhost:9092

You can download the latest JAR from the official GitHub repo.

🏁 Final Thoughts

Kafdrop doesn’t replace Kafka — it reveals Kafka.

If you’re learning, building, or debugging with Kafka, Kafdrop gives you visibility into everything that’s happening.

It’s a must-have tool for:

• Beginners exploring Kafka
• Developers debugging issues
• Teams monitoring production systems

Once you install Kafdrop, you'll never want to work with Kafka blind again 😄