Method connect

lib/cluster/index.ts:191–306

* Connect to a cluster

()

   * Connect to a cluster
   */
  connect(): Promise<void> {
    return new Promise((resolve, reject) => {
      if (
        this.status === "connecting" ||
        this.status === "connect" ||
        this.status === "ready"
      ) {
        reject(new Error("Redis is already connecting/connected"));
        return;
      }

      const epoch = ++this.connectionEpoch;
      this.setStatus("connecting");

      this.resolveStartupNodeHostnames()
        .then((nodes) => {
          if (this.connectionEpoch !== epoch) {
            debug(
              "discard connecting after resolving startup nodes because epoch not match: %d != %d",
              epoch,
              this.connectionEpoch
            );
            reject(
              new RedisError(
                "Connection is discarded because a new connection is made"
              )
            );
            return;
          }
          if (this.status !== "connecting") {
            debug(
              "discard connecting after resolving startup nodes because the status changed to %s",
              this.status
            );
            reject(new RedisError("Connection is aborted"));
            return;
          }
          this.connectionPool.reset(nodes);

          if (this.options.shardedSubscribers) {
            this.shardedSubscribers
              .reset(this.slots, this.connectionPool.getNodes("all"))
              .catch((err) => {
                // TODO should we emit an error event here?
                debug("Error while starting subscribers: %s", err);
              });
          }

          const readyHandler = () => {
            this.setStatus("ready");
            this.retryAttempts = 0;
            this.executeOfflineCommands();
            this.resetNodesRefreshInterval();
            resolve();
          };

          let closeListener: () => void = undefined;
          const refreshListener = () => {