根据外部(例如用户)输入更改Uber Cadence睡眠时间 [英] Changing the Uber Cadence Sleep time based on external (e.g. user) input

问题描述

是否有Cadence工作流基于外部输入更改睡眠时间的示例?

Is there an example of a Cadence workflow changing the sleep duration based on external input?

我要寻找的场景是这样的:工作流程进入睡眠状态直到X时刻，但是在睡眠开始之后但尚未完成之前，有一个外部触发器导致时间X变为时间Y.Y可以是可以早于X.它甚至可以早于现在"，这应该立即释放睡眠.

The scenario I'm looking for is this: the workflow goes into sleep until time X but after the sleep starts but before it completes, there is an external trigger that causes time X to change to time Y. Y can either be later or earlier than X. It can even be earlier than "now", which should release the sleep immediately.

推荐答案

以下是您要查找的代码段

Here is code snippet for what you are looking for

func SampleTimerWorkflow(ctx workflow.Context, timerDelay time.Duration) error 
{
    logger := workflow.GetLogger(ctx)
    resetCh := workflow.GetSignalChannel(ctx, "reset")

    timerFired := false
    delay := timerDelay
    for ;!timerFired; {
        selector := workflow.NewSelector(ctx)

        logger.Sugar().Infof("Setting up a timer to fire after: %v", delay)
        timerCancelCtx, cancelTimerHandler := workflow.WithCancel(ctx)
        timerFuture := workflow.NewTimer(timerCancelCtx, delay)
        selector.AddFuture(timerFuture, func(f workflow.Future) {
            logger.Info("Timer Fired.")
            timerFired = true
        })

        selector.AddReceive(resetCh, func(c workflow.Channel, more bool) {
            logger.Info("Reset signal received.")
            logger.Info("Cancel outstanding timer.")
            cancelTimerHandler()

            var t int
            c.Receive(ctx, &t)
            logger.Sugar().Infof("Reset delay: %v seconds", t)
            delay = time.Second * time.Duration(t)
        })

        logger.Info("Waiting for timer to fire.")
        selector.Select(ctx)
    }

    workflow.GetLogger(ctx).Info("Workflow completed.")
    return nil
}

现在您可以发送信号将计时器重置为10秒，如下所示:

Now you can send a signal to reset the timer to 10 seconds like below:

cadence-cli --domain <domain> wf signal -w <workflow_id>  --name reset --input 10

这篇关于根据外部(例如用户)输入更改Uber Cadence睡眠时间的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！