async-substrate-interface

Warnings

• breaking Version 1.6.4 introduced changes to fix the 'legacy (old) runtimeApi'. Users relying on older runtime API interaction patterns might need to update their code to align with these changes.
  Fix: Review the `v1.6.4` changelog and your Substrate node's API documentation for specifics on updated runtime API interactions. Adjust your code to use the modern API.
• deprecated Support for Python 3.9 was officially removed in version 1.6.2. Attempts to use the library with Python 3.9 or older will likely result in installation or runtime errors.
  Fix: Upgrade your Python environment to version 3.10, 3.11, 3.12, 3.13, or 3.14. The library currently requires Python `<3.15,>=3.10`.
• gotcha While designed to be 'mostly API-compatible with py-substrate-interface', the library is explicitly stated as 'about 90% API compatible' and 'its own library'. This implies that subtle differences in API or behavior may exist.
  Fix: When migrating from `py-substrate-interface` or developing, carefully review the `async-substrate-interface` documentation and test critical paths to identify any API deviations or behavioral changes.
• gotcha The library employs various caching mechanisms (in-memory and disk-based via `DiskCachedAsyncSubstrateInterface`). Cache sizes are configurable via environment variables (`SUBSTRATE_CACHE_METHOD_SIZE`, `SUBSTRATE_RUNTIME_CACHE_SIZE`), and disk caching is keyed by the network URI.
  Fix: Be aware of these caching behaviors. Ensure environment variables are set correctly if you wish to override defaults. If using `DiskCachedAsyncSubstrateInterface` with multiple networks, remember that caches are separate per URI, which is usually desired but important to understand.
• gotcha The documentation suggests that while `AsyncSubstrateInterface` can be used directly, it is generally recommended to use it as part of `AsyncSubtensor` when operating within the Bittensor ecosystem.
  Fix: If your application is part of the Bittensor ecosystem, consider leveraging `AsyncSubtensor` for a more integrated and potentially optimized experience. If using `AsyncSubstrateInterface` directly, be mindful of any Bittensor-specific conventions or helper methods you might be missing.

Install

• pip install async-substrate-interface Install stable version

Imports

• AsyncSubstrateInterface

  from async_substrate_interface import AsyncSubstrateInterface

Quickstart

Initializes an `AsyncSubstrateInterface` to connect to a Substrate node (e.g., Polkadot) and performs an asynchronous query for an account's system data. Ensure an `asyncio` event loop is running to execute the main function.

import asyncio
from async_substrate_interface import AsyncSubstrateInterface

async def main():
    substrate = AsyncSubstrateInterface(
        url="wss://rpc.polkadot.io"
    )
    async with substrate:
        result = await substrate.query(
            module='System',
            storage_function='Account',
            params=['5CZs3T15Ky4jch1sUpSFwkUbYEnsCfe1WCY51fH3SPV6NFnf'] # Example address
        )
        print(result)

if __name__ == '__main__':
    asyncio.run(main())