multiprocessing.Pool
让我发疯了...
我想升级许多软件包,对于每一个软件包,我都必须检查是否有更高的版本。这是由check_one
功能。
主要代码在Updater.update
方法:我创建 Pool 对象并调用map()
方法。
这是代码:
def check_one(args):
res, total, package, version = args
i = res.qsize()
logger.info('\r[{0:.1%} - {1}, {2} / {3}]',
i / float(total), package, i, total, addn=False)
try:
json = PyPIJson(package).retrieve()
new_version = Version(json['info']['version'])
except Exception as e:
logger.error('Error: Failed to fetch data for {0} ({1})', package, e)
return
if new_version > version:
res.put_nowait((package, version, new_version, json))
class Updater(FileManager):
# __init__ and other methods...
def update(self):
logger.info('Searching for updates')
packages = Queue.Queue()
data = ((packages, self.set_len, dist.project_name, Version(dist.version)) \
for dist in self.working_set)
pool = multiprocessing.Pool()
pool.map(check_one, data)
pool.close()
pool.join()
while True:
try:
package, version, new_version, json = packages.get_nowait()
except Queue.Empty:
break
txt = 'A new release is avaiable for {0}: {1!s} (old {2}), update'.format(package,
new_version,
version)
u = logger.ask(txt, bool=('upgrade version', 'keep working version'), dont_ask=self.yes)
if u:
self.upgrade(package, json, new_version)
else:
logger.info('{0} has not been upgraded', package)
self._clean()
logger.success('Updating finished successfully')
当我运行它时,我收到这个奇怪的错误:
Searching for updates
Exception in thread Thread-1:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__args, **self.__kwargs)
File "/usr/local/lib/python2.7/dist-packages/multiprocessing/pool.py", line 225, in _handle_tasks
put(task)
PicklingError: Can't pickle <type 'thread.lock'>: attribute lookup thread.lock failed