Add configurable timeout for CCIP-read client

[eth-limo]

Describe the Feature

Thinking ahead for ENSv2 where CCIP will play a bigger role, it would be great to be able to define a client timeout option.

Code Example

provider.ccipReadTimeout = 3s

[adraffy]

import type { AbstractProvider } from "ethers";

const CCIP_TIMEOUT = Symbol("CcipReadTimeout");

function setCcipReadTimeout(
	provider: AbstractProvider & { [CCIP_TIMEOUT]?: number },
	timeout: number
) {
	if (!(CCIP_TIMEOUT in provider)) {
		const { emit } = provider;
		provider.emit = (e, ...a) => {
			if (e === "debug" && a[0]?.action === "sendCcipReadFetchRequest") {
				a[0].request.timeout = provider[CCIP_TIMEOUT];
			}
			return emit.call(provider, e, ...a);
		};
	}
	provider[CCIP_TIMEOUT] = timeout;
}

// ********************************************************************************
import { JsonRpcProvider } from "ethers";
import { createServer } from "node:http";
import assert from "node:assert";

const T = 100;

const server = createServer(async (_, res) => {
	await new Promise((f) => setTimeout(f, 100));
	res.end(JSON.stringify({ data: "0x" }));
});
await new Promise((f) => server.listen(f));

const p = new JsonRpcProvider("https://eth.drpc.org");

function go() {
	return p.ccipReadFetch({ to: "x" }, "0x", [
		`http://localhost:${server.address().port}`,
	]);
}

setCcipReadTimeout(p, T / 2);
await assert.rejects(go);

setCcipReadTimeout(p, T * 2);
await go();

server.close();

oops, I think that should be emit.call(provider, e, ...a);

[eth-limo]

Thanks @adraffy this is awesome!