💬 Chat Application with Kafka

A distributed chat application using Apache Kafka for message processing. Implemented Feature A: all users exchange messages in one shared topic, seeing each other's messages in real time.

📌 Feature A: Single Kafka topic

Within Feature A:

• All users connect to a single Kafka topic chat
• All sent messages are visible to all users
• No separation by chat rooms (unlike Feature B)
• No message filtering (unlike Feature C)

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🚀 Launching a Project (Universal Instructions)

🧩 Requirements

• Python 3.8+
• Apache Kafka (installed and configured)
• zsh (macOS default), bash or cmd (for Windows) installed
• Git

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🔧 Installation

1. Clone repository

   git clone https://github.com/bluvvis/chat-kafka.git
   cd chat-kafka

2. Create and activate a virtual environment

   macOS / Linux:

   python3 -m venv venv
   source venv/bin/activate

   Windows (cmd):

   python -m venv venv
   venv\Scripts\activate

3. Install dependencies

   pip install -r requirements.txt

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⚙️ Launching Kafka

macOS (installed via Homebrew):

Open a separate terminal window and run:

zookeeper-server-start /opt/homebrew/etc/kafka/zookeeper.properties

Then in a new terminal window:

kafka-server-start /opt/homebrew/etc/kafka/server.properties

Linux (Kafka downloaded manually):

In the Kafka directory:

bin/zookeeper-server-start.sh config/zookeeper.properties

New window:

bin/kafka-server-start.sh config/server.properties

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🧪 Creating a Kafka topic

Open a new terminal and run:

kafka-topics --create \
  --topic chat \
  --bootstrap-server localhost:9092 \
  --partitions 1 \
  --replication-factor 1

Check the topic availability:

kafka-topics --list --bootstrap-server localhost:9092

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Windows (Kafka downloaded manually):

In the Kafka directory:

.\bin\windows\zookeeper-server-start.bat .\config\zookeeper.properties

New window:

.\bin\windows\kafka-server-start.bat .\config\server.properties

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🧪 Creating a Kafka topic

Open a new terminal and run:

kafka-topics.bat --create --bootstrap-server localhost:9092 --topic chat --partitions 1 --replication-factor 1

Check the topic availability:

kafka-topics.bat --list --bootstrap-server localhost:9092

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💬 Starting a chat

1. Window 1 - Consumer:

   python3 consumer.py

   You should see:

   Kafka Chat Consumer started. Listening for messages...
   

2. Window 2 - Producer (sender):

   python3 producer.py

   Enter a username, such as bluvvis, and send messages. They will appear in all running consumers.

3. Multiple windows: You can run multiple producer.py in separate terminals to emulate multiple users.

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✅ Validation

• ✅ General topic: All users are connected to one topic chat
• ✅ Real time: Messages are instantly delivered and displayed
• ✅ Verification: Testing was carried out manually through several terminals (producer and consumer)
• ❌ Isolation and filtering: Not applicable - Feature A was selected according to the technical specifications
• ✅ Message order: The sending order is preserved

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📁 Project structure

chat-kafka/
├── consumer.py         # Message recipient
├── producer.py         # Message Sender
├── requirements.txt    # Python Dependencies
├── README.md           # Project Description
└── venv/               # Virtual environment (add to .gitignore)

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🧑‍💻 Authors

Grigorij Belaev, Farit Sharafutdinov, Batraz Dzesov, Stanislav Delyukov
GitHub: @bluvvis