dochain-block

Prefect Blocks for authentication and connection management.

Overview

dochain-block is a Prefect Block distribution package that provides reusable authentication and connection blocks for various services. The project is designed with a modular architecture to easily add new authentication modules.

Features

• Modular Authentication Blocks: Each service has its own dedicated authentication block
• Secure Credential Management: Built on Prefect's secure block system
• Multiple Authentication Methods: Support for username/password, API keys, tokens, and more
• Async-First Design: Optimized for Prefect's async execution model
• Easy Integration: Seamless integration with Prefect flows and deployments

Installation

# Create virtual environment
uv venv
source .venv/bin/activate  # Unix/macOS
# or
.\.venv\Scripts\activate   # Windows

# Install the package
uv pip install -e .

Available Authentication Blocks

NacosBlock

Connect to Nacos service discovery and configuration management platform.

Supported Authentication Methods:

• Username/Password
• Access Key/Secret Key
• Bearer Token

Features:

• Configuration management
• Service discovery
• Health checks
• Namespace support

Usage Example

from prefect import flow
from dochain_block import NacosBlock

@flow
def nacos_config_flow():
    # Load Nacos block
    nacos = NacosBlock.load("my-nacos-connection")

    # Get configuration
    config = asyncio.run(nacos.get_config("app-config", "DEFAULT_GROUP"))
    return config

# Save block configuration
nacos_block = NacosBlock(
    name="my-nacos-connection",
    server_url="http://localhost:8848/nacos",
    username="nacos",
    password="nacos",
    namespace="public"
)

nacos_block.save("my-nacos-connection")

Development

Adding New Authentication Modules

1. Create a new module in src/dochain_block/auth/
2. Inherit from AuthBlock base class
3. Implement required methods:
   • authenticate(): Main authentication logic
   • Optional: validate_credentials(), refresh_credentials()
4. Register the block in __init__.py

Example: New Authentication Module

from ..core.base_block import AuthBlock
from pydantic import Field, SecretStr

class MyServiceBlock(AuthBlock):
    """Authentication block for MyService"""

    api_key: SecretStr = Field(..., description="API key for MyService")
    base_url: str = Field(..., description="Base URL for MyService")

    _block_type_name = "MyService Authentication"

    async def authenticate(self, **kwargs):
        # Implement authentication logic
        return {
            "authenticated": True,
            "access_token": "your-token"
        }

Development Commands

# Install development dependencies
uv add --dev pytest pytest-asyncio pytest-cov

# Run tests
uv run pytest

# Run tests with coverage
uv run pytest --cov=dochain_block

# Run example
uv run python examples/nacos_example.py

Requirements

• Python 3.11+
• Prefect >= 3.4.24
• Pydantic >= 2.12.3
• httpx >= 0.28.1

License

[Add your license information here]

Contributing

[Add contribution guidelines here]