Metadata-Version: 2.3
Name: spakky-kafka
Version: 6.4.0
Summary: Apache Kafka plugin for Spakky framework
Author: Spakky
Author-email: Spakky <sejong418@icloud.com>
License: MIT
Requires-Dist: aiokafka>=0.13.0
Requires-Dist: confluent-kafka>=2.14.0
Requires-Dist: pydantic>=2.12.5
Requires-Dist: pydantic-settings>=2.13.1
Requires-Dist: spakky-event>=6.4.0
Requires-Dist: spakky-tracing>=6.4.0
Requires-Python: >=3.11
Description-Content-Type: text/markdown

# Spakky Kafka

Apache Kafka plugin for [Spakky Framework](https://github.com/E5presso/spakky-framework).

## Installation

```bash
pip install spakky-kafka
```

Or install via Spakky extras:

```bash
pip install spakky[kafka]
```

## Configuration

Set environment variables with the `SPAKKY_KAFKA__` prefix:

```bash
export SPAKKY_KAFKA__GROUP_ID="my-consumer-group"
export SPAKKY_KAFKA__CLIENT_ID="my-app"
export SPAKKY_KAFKA__BOOTSTRAP_SERVERS="localhost:9092"
export SPAKKY_KAFKA__AUTO_OFFSET_RESET="earliest"  # earliest, latest, none
```

### SASL Authentication (Optional)

```bash
export SPAKKY_KAFKA__SECURITY_PROTOCOL="SASL_SSL"
export SPAKKY_KAFKA__SASL_MECHANISM="PLAIN"
export SPAKKY_KAFKA__SASL_USERNAME="username"
export SPAKKY_KAFKA__SASL_PASSWORD="password"
```

### Topic Configuration (Optional)

```bash
export SPAKKY_KAFKA__NUMBER_OF_PARTITIONS="3"
export SPAKKY_KAFKA__REPLICATION_FACTOR="1"
```

## Usage

### Event Publishing

```python
from spakky.core.common.mutability import immutable
from spakky.domain.models.event import AbstractIntegrationEvent
from spakky.event.event_publisher import IEventPublisher
from spakky.core.pod.annotations.pod import Pod

@immutable
class UserCreatedEvent(AbstractIntegrationEvent):
    user_id: int
    email: str

@Pod()
class UserService:
    def __init__(self, publisher: IEventPublisher) -> None:
        self.publisher = publisher

    def create_user(self, email: str) -> User:
        user = User(email=email)
        self.publisher.publish(UserCreatedEvent(user_id=user.id, email=email))
        return user
```

### Event Consuming

```python
from spakky.event.stereotype.event_handler import EventHandler, on_event

@EventHandler()
class UserEventHandler:
    def __init__(self, notification_service: NotificationService) -> None:
        self.notification_service = notification_service

    @on_event(UserCreatedEvent)
    async def on_user_created(self, event: UserCreatedEvent) -> None:
        await self.notification_service.send_welcome_email(event.email)
```

### Async Variants

For async applications, use `IAsyncEventPublisher`:

```python
from spakky.event.event_publisher import IAsyncEventPublisher

@Pod()
class AsyncUserService:
    def __init__(self, publisher: IAsyncEventPublisher) -> None:
        self.publisher = publisher

    async def create_user(self, email: str) -> User:
        user = User(email=email)
        await self.publisher.publish(UserCreatedEvent(user_id=user.id, email=email))
        return user
```

## Distributed Tracing

`spakky-tracing`은 필수 의존성으로 자동 설치됩니다. `ITracePropagator`가 컨테이너에 등록되어 있으면 이벤트 발행/소비 시 `TraceContext`가 자동으로 전파됩니다.

- **발행 측**: `IEventTransport.send()` 시 현재 `TraceContext`를 Kafka 메시지 헤더에 주입합니다
- **소비 측**: 수신 메시지에서 `TraceContext`를 추출하여 자식 스팬을 생성합니다
- 헤더가 없으면 새로운 루트 트레이스를 시작합니다

## Features

- **Automatic topic creation**: Topics are created based on event type names
- **Sync and Async support**: Both synchronous and asynchronous publishers/consumers
- **Background service pattern**: Consumer polling runs as a background service
- **Pydantic serialization**: Events are serialized/deserialized using Pydantic
- **Confluent Kafka client**: Built on the robust `confluent-kafka` library
- **Distributed tracing**: `spakky-tracing` integration for cross-service trace propagation

## Components

| Component | Description |
|-----------|-------------|
| `KafkaEventTransport` | Synchronous event transport (`IEventTransport`) |
| `AsyncKafkaEventTransport` | Asynchronous event transport (`IAsyncEventTransport`) |
| `KafkaEventConsumer` | Synchronous event consumer (background service) |
| `AsyncKafkaEventConsumer` | Asynchronous event consumer (background service) |
| `KafkaConnectionConfig` | Configuration via environment variables |

## License

MIT License
