# JSON-RPC Python Client
Library for interacting with JSON-RPC servers. Implements the
[JSON-RPC 2.0 spec](https://www.jsonrpc.org/specification), as well as
first-class support for the subscription streaming endpoints exposed by
most blockchain RPC interfaces (e.g. Ethereum, Solana) for JSON-RPC websockets
connections.
## Features
- Websockets connection wrapper with full support for matching request IDs to responses and subscription updates to subscription IDs
- Classes for (de)serializing JSON-RPC spec compliant message types
## Installation
```
$ pip install bx-jsonrpc-py
```
## Websockets Streaming
Many blockchains use a subscription RPC endpoint with JSON-RPC notifications
to provide real-time event streams of updates in the network. They usually look
something like this:
```
// create subscription
>> {"id": 1, "method": "subscribe", "params": ["feedName"]}
<< {"jsonrpc":"2.0","id":1,"result":"subscriptionID"}
// incoming notifications
<< {"jsonrpc":"2.0","method":"subscribe","params":{"subscription":"subscriptionID","result":"data"}}}
<< {"jsonrpc":"2.0","method":"subscribe","params":{"subscription":"subscriptionID","result":"data}}}
// cancel subscription
>> {"id": 1, "method": "unsubscribe", "params": ["subscriptionID"]}
<< {"jsonrpc":"2.0","id":1,"result":true}
```
Some examples: [go-ethereum](https://geth.ethereum.org/docs/rpc/pubsub), [solana](https://docs.solana.com/developing/clients/jsonrpc-api#subscription-websocket)
The included `jsonrpc.WsRpcConnection` class fully implements this feature.
## Usage
```python
import jsonrpc
async with jsonrpc.WsRpcConnection("ws://...") as ws:
print(await ws.call("method", {"param": "value"}))
subscription_id = await ws.subscribe(
"feedname", {"option": "value"}
)
async for notification in ws.notifications_for_id(subscription_id):
print(notification)
```
See `examples/client.py` for a working sample.
## Anticipated Future Work
- Reconnection support for websockets to reconnect and resubscribe to former feeds
## Comments / Questions
Feel free to open up a Github issue to discuss enhancements or problems.
MIT License
Copyright (c) 2022 bloXroute Labs
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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