Method processWaitQueue

src/cmap/connection_pool.ts:724–816

()

  }

  private processWaitQueue() {
    if (this.processingWaitQueue) {
      return;
    }
    this.processingWaitQueue = true;

    while (this.waitQueueSize) {
      const waitQueueMember = this.waitQueue.first();
      if (!waitQueueMember) {
        this.waitQueue.shift();
        continue;
      }

      if (waitQueueMember.cancelled) {
        this.waitQueue.shift();
        continue;
      }

      if (this.poolState !== PoolState.ready) {
        const reason = this.closed ? 'poolClosed' : 'connectionError';
        const error = this.closed ? new PoolClosedError(this) : new PoolClearedError(this);
        this.emitAndLog(
          ConnectionPool.CONNECTION_CHECK_OUT_FAILED,
          new ConnectionCheckOutFailedEvent(this, reason, waitQueueMember.checkoutTime, error)
        );
        this.waitQueue.shift();
        waitQueueMember.reject(error);
        continue;
      }

      if (!this.availableConnectionCount) {
        break;
      }

      const connection = this.connections.shift();
      if (!connection) {
        break;
      }

      if (!this.destroyConnectionIfPerished(connection)) {
        this.checkedOut.add(connection);
        this.emitAndLog(
          ConnectionPool.CONNECTION_CHECKED_OUT,
          new ConnectionCheckedOutEvent(this, connection, waitQueueMember.checkoutTime)
        );

        this.waitQueue.shift();
        waitQueueMember.resolve(connection);
      }
    }

    const { maxPoolSize, maxConnecting } = this.options;
    while (
      this.waitQueueSize > 0 &&
      this.pendingConnectionCount < maxConnecting &&
      (maxPoolSize === 0 || this.totalConnectionCount < maxPoolSize)
    ) {
      const waitQueueMember = this.waitQueue.shift();