kafka-ts/dist/auth/oauthbearer.js

**KafkaTS** is a Apache Kafka client library for Node.js. It provides both a low-level API for communicating directly with the Apache Kafka cluster and high-level APIs for publishing and subscribing to Kafka topics.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.oAuthAuthenticator = exports.oAuthBearer = void 0;
const api_1 = require("../api");
const number_1 = require("../utils/number");
const retry_1 = require("../utils/retry");
const MAX_INT = Math.pow(2, 31) - 1;
const oAuthBearer = (getToken) => {
    return {
        mechanism: 'OAUTHBEARER',
        authenticate: async ({ sendRequest }) => {
            const { access_token: accessToken } = await getToken();
            const sep = String.fromCharCode(1);
            const authBytes = `n,,${sep}auth=Bearer ${accessToken}${sep}${sep}`;
            await sendRequest(api_1.API.SASL_AUTHENTICATE, { authBytes: Buffer.from(authBytes) });
        },
    };
};
exports.oAuthBearer = oAuthBearer;
const oAuthAuthenticator = ({ endpoint, clientId, clientSecret, refreshThresholdSeconds = 15, }) => {
    let tokenPromise = createToken(endpoint, {
        grant_type: 'client_credentials',
        client_id: clientId,
        client_secret: clientSecret,
    });
    const scheduleRefresh = () => {
        tokenPromise.then((token) => {
            const refreshInMs = (0, number_1.clamp)((token.expires_in - refreshThresholdSeconds) * 1000, 1, MAX_INT);
            setTimeout(() => {
                tokenPromise = createToken(endpoint, {
                    grant_type: 'refresh_token',
                    client_id: clientId,
                    client_secret: clientSecret,
                    refresh_token: token.refresh_token,
                });
                scheduleRefresh();
            }, refreshInMs);
        });
    };
    scheduleRefresh();
    return () => tokenPromise;
};
exports.oAuthAuthenticator = oAuthAuthenticator;
const createToken = async (endpoint, body) => {
    return (0, retry_1.withRetry)((0, retry_1.exponentialBackoff)(100), 5)(async () => {
        const response = await fetch(endpoint, {
            method: 'POST',
            headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
            body: new URLSearchParams(body),
        });
        if (!response.ok) {
            throw new Error(`Failed to obtain OAuth token: ${await response.text()}`);
        }
        return response.json();
    });
};