@skyware/labeler/dist/util/resolveHandle.js

A lightweight alternative to Ozone for operating an atproto labeler.

import dns from "dns/promises";
export async function resolveHandle(handle) {
    const dnsPromise = resolveDns(handle);
    const httpAbort = new AbortController();
    const httpPromise = resolveHttp(handle, httpAbort.signal).catch(() => undefined);
    const dnsRes = await dnsPromise;
    if (dnsRes) {
        httpAbort.abort();
        return dnsRes;
    }
    const res = await httpPromise;
    if (res) {
        return res;
    }
}
async function resolveDns(handle) {
    let chunkedResults;
    try {
        chunkedResults = await dns.resolveTxt(`_atproto.${handle}`);
    }
    catch (err) {
        return undefined;
    }
    return parseDnsResult(chunkedResults);
}
async function resolveHttp(handle, signal) {
    const url = new URL("/.well-known/atproto-did", `https://${handle}`);
    try {
        const res = await fetch(url, signal ? { signal } : undefined);
        const did = (await res.text()).split("\n")[0].trim();
        if (typeof did === "string" && did.startsWith("did:")) {
            return did;
        }
        return undefined;
    }
    catch (err) {
        return undefined;
    }
}
function parseDnsResult(chunkedResults) {
    const results = chunkedResults.map((chunks) => chunks.join(""));
    const found = results.filter((i) => i.startsWith("did="));
    if (found.length !== 1) {
        return undefined;
    }
    return found[0].slice("did=".length);
}