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Client

  • NodeJS
    • nats - 不支持 websocket
  • NodeJS/Browser - Websocket
    • nats.ws
  • 官方 Client
    • WebSocket
    • C, C#, Crystal, Deno, Elixir, Go, Java, Nginx, NodeJS, Ruby, Pure Ruby
    • Python Asyncio, Python Torando, Rust
  • Connectors/Utils
    • 官方: Spark, Redis PubSub, Kafka Bridge, MQ Series Bridge, Replicator
  • 参考 
// 最多 10 次重连
export const DEFAULT_MAX_RECONNECT_ATTEMPTS = 10;
// 重连随机间隔范围
export const DEFAULT_JITTER = 100;
// jitter for tls
export const DEFAULT_JITTER_TLS = 1000;
// Ping interval
export const DEFAULT_PING_INTERVAL = 2 * 60 * 1000; // 2 minutes
export const DEFAULT_MAX_PING_OUT = 2;

// DISCONNECT Parameters, 2 sec wait, 10 tries
// 重连间隔
export const DEFAULT_RECONNECT_TIME_WAIT = 2 * 1000;

// 重连间隔计算逻辑
const reconnectDelayHandler = () => {
  let extra = options.tls ? options.reconnectJitterTLS : options.reconnectJitter;
  if (extra) {
    extra++;
    extra = Math.floor(Math.random() * extra);
  }
  return options.reconnectTimeWait + extra;
};

Request/Reply​

  • Request/Reply
    • client: subscribe INBOX
    • client: publish subject
    • server: reply -> publish(msg.replay) -> client.INBOX
    • client: handle reply
    • client: unsubscribe INBOX

NodeJS Websocket​

function polyfillWebSocket(ws?: any): MaybePromise<boolean> {
  const globalThis = getGlobalThis();
  if ('WebSocket' in globalThis) {
    return false;
  }
  if (ws) {
    const { WebSocket } = ws;
    Object.assign(globalThis, { WebSocket });
  }
  return import('ws').then((ws) => polyfillWebSocket(ws));
}

const { connect } = await import('nats.ws');
const client = await connect({
  servers: ['wss://nats.example.com:443'],
});
console.log(client.stats());