@ubiquity/rpc-handler

This packages leverages Chainlist's network RPC list to return the lowest latency provider from the list for any given network ID.

Features

• Returns the lowest latency provider for a given network ID
• Drops bad endpoints from the list and creates a runtime/local storage cache
• Can re-test the cached RPCs by calling handler.getFastestRpcProvider()
• Can be used in both the browser and Node.js
• Fully configurable and extendable
• Only uses endpoints which Chainlist report as tracking no data (see extraRpcs.js)

Installation

yarn add @ubiquitydao/rpc-handler

Usage

• Import the handler for your environment

Browser

import { HandlerConstructorConfig } from "@ubiquity/rpc-handler/dist/esm/src/handler";
import { RPCHandler } from "@ubiquity/rpc-handler/dist/esm/src/rpc-handler";

export function useHandler(networkId: number) {
  const config: HandlerConstructorConfig = {
    networkId,
    autoStorage: true,
    cacheRefreshCycles: 5,
  };
  // No RPCs are tested at this point
  return new RPCHandler(config);
}

import { useHandler } from "./rpc-handler";
const handler = useHandler(networkId);

// Now the RPCs are tested
app.provider = await handler.getFastestRpcProvider();

Node.js

import { HandlerConstructorConfig } from "@ubiquity/rpc-handler/dist/cjs/src/handler";
import { RPCHandler } from "@ubiquity/rpc-handler/dist/cjs/src/rpc-handler";

const config: HandlerConstructorConfig = {
  networkId: 100;
  autoStorage: false, // only applies to local storage
  cacheRefreshCycles: 5,
};

async function main() {
  const handler = new RPCHandler(config);
  return await handler.getFastestRpcProvider();
}

main().then(console.log).catch(console.error);

Notes

• The RPCs are not tested on instantiation, but are tested on each call to handler.getFastestRpcProvider() or handler.testRpcPerformance()

• networkId is the only required configuration option

• See the full config object (optionally passed in the constructor) for more options

• Local storage is not enabled by default, but can be enabled by passing autoStorage: true in the config object

• The cacheRefreshCycles is the number of roundtrips made before clearing the cache and re-testing all RPCs again

Testing

• In order to run the tests the package must first be built, this is required otherwise networkRpcs will be empty as the RPCs are injected at build time

yarn test