@ubiquity-dao/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 @ubiquity-dao/rpc-handler

Usage

• Config options with null are optional, but still need to be passed as null

import { RPCHandler, HandlerConstructorConfig } from "@ubiquity-dao/rpc-handler/";

export function useHandler(networkId: number) {
  const config: HandlerConstructorConfig = {
    networkId: 1,
    rpcTimeout: 1500,
    autoStorage: false,
    cacheRefreshCycles: 10,
    networkName: null, // the name will be deduced from the networkId, unless using a custom network
    networkRpcs: null, // same as networkName, but for injecting additional RPCs
    runtimeRpcs: null, // same as networkRpcs, although these are considered error-free
  };
  // 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();

Notes

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

• 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

• Tests have a specific build in order to run yarn test will produce this build and run the tests.
• After testing, re-build using yarn build for the original build

yarn test

• This below will only work after yarn build has been run and will fail under test conditions

npx tsx tests/script-test.ts