为什么gevent。直到调用Greenlet.join，才执行参数化函数?

I'd like to issue an asynchronous HTTP POST request using gevent -- I don't care about the response, I simply want to execute the request as soon as possible. However, whenever I attempt to do so using gevent.spawn, the request never executes. I know this because calling the .ready() or .successful() methods on the Greenlet that is returned from gevent.spawn always returns False.

我想使用gevent发出一个异步HTTP POST请求——我不关心响应，我只想尽快执行请求。但是，每当我尝试使用gevent时。衍生，请求永远不会执行。我之所以知道这一点，是因为在gevent返回的Greenlet上调用.ready()或.success()方法。产卵总是返回False。

However, the Greenlet has started, because if I call glet = gevent.spawn(...), then glet.start(), I get an error saying AssertionError: Greenlet already started.

然而，Greenlet已经启动，因为如果我调用glet = gevent.spawn(…)，然后glet.start()，就会得到一个输入AssertionError: Greenlet已经启动的错误。

The only time I get a glet.ready() == True is when I call glet.join(), but this is a blocking operation. How can I have the Greenlet execute without waiting for it to complete?

我得到一个glet.ready() = True的唯一时间是当我调用glet.join()时，但是这是一个阻塞操作。我怎么能让绿线执行而不等待它完成?

1 个解决方案

#1

Since greenlets are cooperative, your new greenlet won't run until you yield to it. After calling spawn, call gevent.sleep(0) to yield and your greenlet should run.

因为greenlets是合作的，所以你的新greenlet不会跑到你屈服为止。在调用spawn之后，调用gevent.sleep(0)来yield，您的greenlet应该运行。

It will continue to run until it does something that causes it to yield (like kicking off that http req). Then your other code can resume again.

它将继续运行，直到它做一些导致它屈服的事情(比如启动http req)。然后你的其他代码可以重新开始。

EDIT:

编辑:

To address your question about grequests, the grequests.send() doc says:

要回答你的问题，grequest。send() doc说:

send(r, pool=None, stream=False)
    Sends the request object using the specified pool. If a pool isn't
    specified this method blocks. Pools are useful because you can specify size
    and can hence limit concurrency

Since you have not specified a pool, the request blocks for your greenlet to finish. In other words, once it returns the greenlet has already completed. To get the response, see glt.get() of the returned greenlet.

由于尚未指定池，因此请求将阻塞您的greenlet以完成。换句话说，一旦它返回，绿点就已经完成了。要获得响应，请参阅glt.get()返回的greenlet。

#1