Method findOrCreate

lib/cluster/ConnectionPool.ts:100–147

* Find or create a connection to the node

(node: RedisOptions, readOnly = false)

   * Find or create a connection to the node
   */
  findOrCreate(node: RedisOptions, readOnly = false): Redis {
    const key = getNodeKey(node);
    readOnly = Boolean(readOnly);

    if (this.specifiedOptions[key]) {
      Object.assign(node, this.specifiedOptions[key]);
    } else {
      this.specifiedOptions[key] = node;
    }

    let redis: Redis;
    if (this.nodes.all[key]) {
      redis = this.nodes.all[key];
      if (redis.options.readOnly !== readOnly) {
        redis.options.readOnly = readOnly;
        debug("Change role of %s to %s", key, readOnly ? "slave" : "master");
        redis[readOnly ? "readonly" : "readwrite"]().catch(noop);
        if (readOnly) {
          delete this.nodes.master[key];
          this.nodes.slave[key] = redis;
        } else {
          delete this.nodes.slave[key];
          this.nodes.master[key] = redis;
        }
      }
    } else {
      debug("Connecting to %s as %s", key, readOnly ? "slave" : "master");
      redis = this.createRedisFromOptions(node, readOnly);
      this.nodes.all[key] = redis;
      this.nodes[readOnly ? "slave" : "master"][key] = redis;

      redis.once("end", () => {
        this.removeNode(key);
        this.emit("-node", redis, key);
        if (!Object.keys(this.nodes.all).length) {
          this.emit("drain");
        }
      });

      this.emit("+node", redis, key);

      redis.on("error", (error) => {
        this.emit("nodeError", error, key);
      });
    }

    return redis;
  }

  /**
   * Reset the pool with a set of nodes.