Python 线程：监视线程并在线程完成后执行附加代码

Question

我有以下代码：

class MyThread(Thread):
    def __init__(self, command, template, env, build_flavor, logger):
        Thread.__init__(self)
        self.command = command
        self.template = template
        self.env = env
        self.build_flavor = build_flavor
        self.logger = logger

    def run(self):
        self.logger.info('Running (%s)...this may take several minutes. Please be patient' % self.build_flavor)
        run_command(self.command, self.template, self.env)
        self.logger.info('Complete (%s)' % self.build_flavor)
        return

然后在另一个 class 中，当我创建实际线程时：

if self.build_type == 'default':
            threads = []
            for t in self.template:
                modify_template(t)
                build_flavor = self.getmatch(t)
                thread = MyThread(packer, t, self.new_env, build_flavor, self.logger)
                thread.setName(build_flavor)
                thread.start()
                threads.append(thread)
            for thread in threads:
                thread.join()
            vmware_create()
            openstack_create()

不幸的是，在线程被 .join() 之后，我在串行调用 vmware_create() 和 openstack_create()。我希望能够在它们各自的线程完成后执行它们中的每一个，这样我就不会在启动其中一个 *_create() 函数之前等待两个线程完成......然后等待第一个完成在执行第二个

之前

即现在 vmware_create() 只会在两个线程都完成后执行，一旦 vmware_create() 完成，openstack_create() 才会开始。我希望能够等待各自的线程完成，然后为首先完成的任何线程执行 _create() 函数，一直等待第二个线程完成，然后一旦完成，立即执行其 _create () 真正并行化的函数。

我还不知道该怎么做，需要一点帮助。

Answer 1

函数是对象。只需将它们交给线程即可：

class MyThread(Thread):
    def __init__(self, command, template, env, build_flavor, logger, func=None):
        Thread.__init__(self)
        self.command = command
        self.template = template
        self.env = env
        self.build_flavor = build_flavor
        self.logger = logger
        self.func = func

    def run(self):
        self.logger.info('Running (%s)...this may take several minutes. Please be patient' % self.build_flavor)
        run_command(self.command, self.template, self.env)
        self.logger.info('Complete (%s)' % self.build_flavor)
        # call func if it is there
        if self.func:
            self.func()
        return

现在，我为前两个线程提供要调用的函数：

if self.build_type == 'default':
    threads = []
    funcs = {0: vmware_create, 1: openstack_create}
    for i, t in enumerate(self.template):
        modify_template(t)
        build_flavor = self.getmatch(t)
        func = funcs.get(i, None)
        thread = MyThread(packer, t, self.new_env, build_flavor, 
                          self.logger, func=func)
        thread.setName(build_flavor)
        thread.start()
        threads.append(thread)
    for thread in threads:
        thread.join()

当然，您可以将它们添加到任何其他线程。

Python 线程：监视线程并在线程完成后执行附加代码

Python threading: monitoring threads and executing additional code after threads complete

python

python-multithreading