wait-for-kafka
Version:
Ensures that certain Kafka topics exist
180 lines (179 loc) • 8.38 kB
JavaScript
;
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
var kafka_node_1 = require("kafka-node");
var bluebird_1 = __importDefault(require("bluebird"));
var lib_1 = require("./lib");
var debug = require('debug')('wait-for-kafka:debug');
function sleep(ms) {
return new Promise(function (resolve) { return setTimeout(resolve, ms); });
}
function client_once(client, ev) {
return new Promise(function (resolve) { return client.once(ev, resolve); });
}
function client_getApiVersions(client) {
return new Promise(function (resolve) { return client.loadMetadataForTopics([], resolve); });
}
function client_load_metadata(client) {
return new Promise(function (resolve) { return client.loadMetadataForTopics([], resolve); });
}
// setup kafka
bluebird_1.default.promisifyAll(kafka_node_1.KafkaClient);
function try_to_connect(kafka_url, abort_after_tries, wait_between_tries_s) {
return __awaiter(this, void 0, void 0, function () {
var tries_left, client, e_1;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
tries_left = abort_after_tries;
_a.label = 1;
case 1:
if (!(tries_left > 0)) return [3 /*break*/, 8];
_a.label = 2;
case 2:
_a.trys.push([2, 5, , 6]);
client = new kafka_node_1.KafkaClient({ kafkaHost: kafka_url });
debug("created client waiting to connect");
return [4 /*yield*/, client_once(client, 'connect')];
case 3:
_a.sent();
return [4 /*yield*/, client_load_metadata(client)];
case 4:
_a.sent();
debug("connected");
return [2 /*return*/, client];
case 5:
e_1 = _a.sent();
debug("Could still not connect to kafka", e_1.message);
return [3 /*break*/, 6];
case 6:
tries_left--;
return [4 /*yield*/, sleep(wait_between_tries_s * 1000)];
case 7:
_a.sent();
return [3 /*break*/, 1];
case 8: throw new Error("Failed to connect to Kafka");
}
});
});
}
function wait_for_kafka(kafka_url, wait_for_topics_list, ensure_topics_list, abort_after_tries, wait_between_tries_s) {
if (wait_for_topics_list === void 0) { wait_for_topics_list = null; }
if (ensure_topics_list === void 0) { ensure_topics_list = null; }
if (abort_after_tries === void 0) { abort_after_tries = 10; }
if (wait_between_tries_s === void 0) { wait_between_tries_s = 5; }
return new Promise(function (orig_resolve, orig_reject) {
try_to_connect(kafka_url, abort_after_tries, wait_between_tries_s).then(function (client) {
var tasks_to_finish = 2;
var resolve = function () {
tasks_to_finish--;
if (tasks_to_finish === 0) {
client.close();
orig_resolve();
}
};
var reject = function (a) {
client.close();
orig_reject(a);
};
/////////////////////////////////////// WAIT FOR TOPICS
if (wait_for_topics_list) {
lib_1.wait_for_topics(client, wait_for_topics_list, abort_after_tries, wait_between_tries_s)
.then(function (success) {
if (!success) {
reject("Timeout waiting for one of the topics:" + wait_for_topics_list);
}
else {
debug("Following topics do exist:", wait_for_topics_list);
resolve();
}
});
}
else {
resolve();
}
//////////////////////////////////// ENSURE KAFKA TOPICS
if (ensure_topics_list) {
lib_1.ensure_topics(client, ensure_topics_list).then(function (success) {
if (!success) {
reject('Error ensuring existence of topics' + ensure_topics_list);
}
else {
debug("Ensured, that following topics do exist:", ensure_topics_list);
resolve();
}
});
}
else {
resolve();
}
}).catch(orig_reject);
});
}
exports.default = wait_for_kafka;
;
if (require.main === module) {
var abort_after_tries = 10;
if (process.env.ABORT_AFTER_TRIES) {
abort_after_tries = parseInt(process.env.ABORT_AFTER_TRIES);
}
var wait_between_tries_s = 5;
if (process.env.WAIT_BETWEEN_TRIES_S) {
wait_between_tries_s = parseInt(process.env.WAIT_BETWEEN_TRIES_S);
}
var kafka_url = process.env.KAFKA_BOOTSTRAP_SERVERS;
var wait_for_topics_raw = process.env.WAIT_FOR_KAFKA_TOPICS;
var wait_for_topics_list = null;
if (wait_for_topics_raw) {
wait_for_topics_list = wait_for_topics_raw.split(",").map(function (x) { return x.trim(); });
}
var ensure_topics_raw = process.env.ENSURE_KAFKA_TOPICS;
var ensure_topics_list = null;
if (ensure_topics_raw) {
ensure_topics_list = JSON.parse(ensure_topics_raw);
}
wait_for_kafka(kafka_url, wait_for_topics_list, ensure_topics_list, abort_after_tries, wait_between_tries_s)
.then(function () { return process.exit(0); })
.catch(function (e) {
console.error("Error:", e);
process.exit(1);
});
}