Question

当我尝试使用__import__ ...实现某种动态类加载时出现以下错误：

No module named pip._vendor.requests.status_codes
Traceback (most recent call last):
  File"/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1536, in __call__
    rv = self.handle_exception(request, response, e)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1530, in __call__
    rv = self.router.dispatch(request, response)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1278, in default_dispatcher
    return route.handler_adapter(request, response)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1102, in __call__
    return handler.dispatch()
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 572, in dispatch
    return self.handle_exception(e, self.app.debug)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 570, in dispatch
    return method(*args, **kwargs)
  File "/base/data/home/apps/s~ticatestdev/2.386059027148196174/tica/tasks.py", line 36, in post
    m = __import__(handler['module'], fromlist=[handler['name']])
  File "/base/data/home/apps/s~ticatestdev/2.386059027148196174/tica/sources/processors.py", line 18, in <module>
    from pip._vendor.requests.status_codes import codes
  ImportError: No module named pip._vendor.requests.status_codes

...或importlib.import_module：

No module named pip._vendor.requests.status_codes
Traceback (most recent call last):
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1536, in __call__
    rv = self.handle_exception(request, response, e)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1530, in __call__
    rv = self.router.dispatch(request, response)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1278, in default_dispatcher
    return route.handler_adapter(request, response)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 1102, in __call__
    return handler.dispatch()
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 572, in dispatch
    return self.handle_exception(e, self.app.debug)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.1/webapp2.py", line 570, in dispatch
    return method(*args, **kwargs)
  File "/base/data/home/apps/s~ticatestdev/2.386058813285719320/tica/tasks.py", line 36, in post
    m = importlib.import_module(handler['module'])
  File "/base/data/home/runtimes/python27/python27_dist/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/base/data/home/apps/s~ticatestdev/2.386058813285719320/tica/sources/processors.py", line 18, in <module>
    from pip._vendor.requests.status_codes import codes
  ImportError: No module named pip._vendor.requests.status_codes

我当然导入了importlib。

我在Google AppEngine服务器上部署我的程序来测试它（我有一个生产URL和一个开发URL）。

以下是代码：

import importlib
import json
import logging
class Process(handlers.BaseHandler):
def post(self):
    parameters = json.loads(self.request.get('parameters'))
    if parameters:
        if 'handler' in parameters:
            handler = parameters['handler']
            m = __import__(handler['module'], fromlist=[handler['name']])
            #m = importlib.import_module(handler['module'])
            task_handler = getattr(m, handler['name'])(parameters)
            #task_handler = getattr(m, handler['name'])(parameters)
            task_handler.startProcessing(parameters)
        else:
            logging.error("python.tasks.Process(): No handler information provided!")
    else:
        logging.error("python.tasks.Process(): No parameters provided!")

和参数内容：

{"dictionary_list": [...], "handler": {"name": "SourceProcessingHandler", "module": "sources.processors"}, "command": "process", "fsm": {}, "language_code": "ja"}

我在谷歌上找不到类似的错误，

我现在想知道，如果我不浪费时间试图用这个复杂的解决方案来超越自己......

可能我应该使用一个将名称与python类相关联的简单字典？

Answer 1

tica/sources/processors.py文件似乎是您的应用程序的一部分。如果是这样，它明确地依赖于pip包，它看起来不是标准python库的一部分，并且不包含在GAE Runtime-Provided Libraries中。这意味着它需要vendored in。

您希望动态加载所有依赖项的所有软件包/模块可能同样需要出售。

在尝试执行动态加载的代码之前，我还会添加更多的健全性检查。至少捕捉和处理ImportError。

旁注：以防task_handler.startProcessing(parameters)占用时间过长导致DeadlineExceededError post请求，您可能希望将执行委托给任务队列或后端执行模块

Google AppEngine动态加载，ImportError：没有名为pip._vendor.requests.status_codes的模块

1 个答案: