Python wrapper for the StreamrProxyClient

This is a Python wrapper for the StreamrProxyClient C++ library. It is used to publish data to the Streamr network.

Installation

python -m pip install libstreamrproxyclient

The package is distributed as a binary wheel and is available for MacOS (arm64 and x86_64) and Linux (arm64 and x86_64).

Usage example

from streamrproxyclient.libstreamrproxyclient import (
    Proxy,
    LibStreamrProxyClient,
    ProxyClient
)

proxy_ethereum_address = "0xd0d14b38d1f6b59d3772a63d84ece0a79e6e1c1f"
proxy_url = "ws://95.216.15.80:44211"
stream_part_id = "0xd2078dc2d780029473a39ce873fc182587be69db/low-level-client#0"
own_ethereum_address = "0xa5374e3c19f15e1847881979dd0c6c9ffe846bd5"
ethereum_private_key = "23bead9b499af21c4c16e4511b3b6b08c3e22e76e0591f5ab5ba8d4c3a5b1820"
 
        
with LibStreamrProxyClient() as lib:
    with ProxyClient(lib, own_ethereum_address, stream_part_id) as client:
        result = client.connect([Proxy(proxy_url, proxy_ethereum_address)])
        assert len(result.errors) == 0
        assert len(result.successful) == 1
        
        result = client.publish(b"Hello from python!", ethereum_private_key)
        assert len(result.errors) == 0
        assert len(result.successful) == 1

API documentation

Classes

Proxy

Contains information about a proxy node in the Streamr network.

Methods:

• __init__(websocket_url: str, ethereum_address: str): Initialize a Proxy instance with websocket URL and Ethereum address
• from_c_proxy(c_proxy): Create Proxy instance from C struct (internal use)

Error

Represents an error from the C library.

Attributes:

• message: Error message string
• code: Error code string
• proxy: Associated Proxy instance if applicable

ProxyClientException

Exception raised when C library operations fail.

Attributes:

• error: The Error instance containing details

ProxyClientResult

Result of proxy client operations.

Attributes:

• errors: List of Error instances if operation had errors
• successful: List of successful Proxy instances

LibStreamrProxyClient

Wrapper for the C library. Use as context manager.

Methods:

• __enter__(): Load and initialize C library
• __exit__(): Cleanup C library

ProxyClient

Main client for interacting with proxies. Use as context manager.

Methods:

• __init__(lib: LibStreamrProxyClient, ownEthereumAddress: str, streamPartId: str): Initialize with library instance, Ethereum address and stream ID
• connect(proxies: list[Proxy]) -> ProxyClientResult: Connect to list of proxies
• publish(data: bytes, ethereumPrivateKey: str = None) -> ProxyClientResult: Publish data to connected proxies

Error Codes

• ERROR_INVALID_ETHEREUM_ADDRESS: Invalid Ethereum address format
• ERROR_INVALID_STREAM_PART_ID: Invalid stream part ID format
• ERROR_PROXY_CLIENT_NOT_FOUND: Proxy client instance not found
• ERROR_INVALID_PROXY_URL: Invalid proxy websocket URL
• ERROR_NO_PROXIES_DEFINED: No proxies provided
• ERROR_PROXY_CONNECTION_FAILED: Failed to connect to proxy
• ERROR_PROXY_BROADCAST_FAILED: Failed to broadcast message to proxy