code: func (p *BlockPuller) Close() {
  	if p.cancelStream != nil {
  		p.cancelStream()
  	}
  	p.cancelStream = nil
  
  	if p.conn != nil {
  		p.conn.Close()
  	}
  	p.conn = nil
  	p.endpoint = ""
  	p.latestSeq = 0
  	p.blockBuff = nil
  }
docs: // Close makes the BlockPuller close the connection and stream
  // with the remote endpoint, and wipe the internal block buffer.