code: func (c *Cluster) CancelStore(storeID uint64) {
  	c.Lock()
  	defer c.Unlock()
  
  	//A store returns context.Cancelled Error when cancel is true.
  	if store := c.stores[storeID]; store != nil {
  		store.cancel = true
  	}
  }
docs: // CancelStore makes the store with cancel state true.