Ethers: MulticallProvider

The MulticallProvider is designed to reduce the latency and large number of calls that can occur, especially on the initial loading of page.

This does not require any multicall contract be deployed to the network, and does not deploy any multicall contract to the network. It is only designed to assist in read-only call operations, and does not currently support sending multicall transactions.

For inspiration, see:

• Ethers v5 multicall
• multicall3

Installing

/home/ricmoo> npm install @ethers-ext/provider-multicall

Usage

import { MulticallProvider } from "@ethers-ext/provider-multicall";

// Create the provider which will serve as the main transport
const provider = new InfuraProvider();

// Crate the multicall provider, which will aggregate calls
const multicaller = new MulticallProvider(provider);

// Connect your contracts to the multicaller
const dai = new Contract("dai.tokens.ethers.eth, daiAbi, multicaller);

// Make your multicalls
const [ sym, name, totalSupply ] = await Promise.all([
  dai.symbol(),
  dai.name(),
  dai.totalSupply(),
]);

API

new MulticallProvider(provider)

Create a new MulticallProvider using provider as the transport.

provider.queueCall(to, data) => Promise<Array<{ status: boolean, data: string }>>

Place a call into the queue to be called on the next drain. Any normal provider.call will call this internally.

provider.drainCallQueue() => Promise<Array<{ status: boolean, data: string }>>

Regardless of the remaining time before the drainInterval, trigger all calls. This must be called explicitly when using manual drain (i.e. the drainInterval is -1).

provider.drainInterval

The drainInterval (by default, 10ms) specifies the interval to aggregate calls within. If the drainInterval is set to 0, then only calls made within a single event loop will be aggregated and if -1 is used then the provider.drainCallQueue MUST be called manually.

Pay special attention when using manual a drainInterval, as it can easily lead to deadlock, if a response is await-ed without another execution in the event loop to trigger a drain.

Contributing

If the multicall contract is changed (./contracts/multicall.sol), then you must call npm run build-solc before the changes will be added to the ./src.ts/_contract.ts file, which is a TypeScript version of the ABI and bytecode, generated using ./src.ts/_build.ts.

Please open a discussion before making any changes. :o).

Notes

This is designed for Ethers v6. For Ethers v5, see the old Multicaller.

License

MIT License.