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我有一個模塊導入問題。使用python 2.6在Ubuntu 10.10Python導入模塊導致NameError
我有在http://www.jejik.com/articles/2007/02/a_simple_unix_linux_daemon_in_python/子類的守護進程的類。我創建了一個包含代碼的模塊的python包，從django項目中導入一些模型。代碼在從類中使用時不起作用，而不是繼承守護進程。該結構看起來是這樣的：
my_module
__init__.py
- bin
- cfg
- core
__init__.py
collection.py
daemon.py
的ItemRepository代碼：
class ItemRepository(object):
"""This class provides an implementation to retrieve configuration data
from the monocle database
"""
def __init__(self, project_path):
if project_path is not None:
sys.path.append(project_path)
try:
from django.core.management import setup_environ
from someproj import settings
setup_environ(settings)
from someproj.someapp.models import ItemConfiguration
except ImportError:
print "Could not import models from web app. Please ensure the\
PYTHONPATH is configured properly"
def get_scheduled_collectors(self):
"""This method finds and returns all ItemConfiguration objects
that are scheduled to run
"""
logging.info('At the error path: %s' % sys.path)
# query ItemConfigs from database
items = ItemConfiguration.objects.filter(disabled=False) #ERROR OCCURS AT THIS LINE
return [item for item in items if item.scheduled]
守護程序代碼（/usr/local/bin/testdaemon.py）：
import sys
from my_module.core.daemon import Daemon
from my_module.core.collection import ItemRepository
import logging
import time
class TestDaemon(Daemon):
default_conf = '/etc/echodaemon.conf'
section = 'echo'
def run(self):
while True:
logging.info('The echo daemon says hello')
ir = ItemRepository(project_path=self.project_path)
items = ir.get_scheduled_collectors() #TRIGGERS ERROR
logging.info('there are %d scheduled items' % len(items))
time.sleep(1)
if __name__ == '__main__':
TestDaemon().main()
錯誤我得到的是「NameError：全局名稱'my_module'未定義」它通過導入但在嘗試調用對象的方法時失敗。我假設它與sys.path/PYTHONPATH有關，但我知道我的django項目正在路徑中，因爲我打印出來了。目前爲止，python文檔或Learning Python還沒有提供幫助。有沒有人有任何見解或知道對模塊進口的很好的參考？
UPDATE：
現在，我已經嘗試簡化問題，使其更容易理解。現在我有一個看起來像一個目錄結構：
/home
/username
/django
/someproj
/web
models.py
/my_module
daemon.py
我在/etc/bash.bashrc設置$ PYTHONPATH變量「/家/用戶名/ Django的。
裏面的testdaemon.py文件進口的樣子：
import logging
from django.core.management import setup_environ
from someproj import settings
setup_environ(settings)
from someproj.web.models import ItemConfiguration
但現在我得到一個ImportError：無模塊名爲 'someproj'。於是我追加了路徑。
import sys
sys.path.append('/home/username/django')
import logging
from django.core.management import setup_environ
from someproj import settings
setup_environ(settings)
from someproj.web.models import ItemConfiguration
現在ImportError說：沒有名爲'web'的模塊。這裏的回溯：
Traceback (most recent call last):
File "testdaemon.py", line 77, in <module>
TestDaemon('/tmp/testdaemon.pid').run()
File "testdaemon.py", line 47, in run
scheduled_items = [item for item in ItemConfiguration.objects.filter(disabled=False) if collector.scheduled]
File "/usr/local/lib/python2.6/dist-packages/django/db/models/manager.py", line 141, in filter
return self.get_query_set().filter(*args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/db/models/query.py", line 550, in filter
return self._filter_or_exclude(False, *args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/db/models/query.py", line 568, in _filter_or_exclude
clone.query.add_q(Q(*args, **kwargs))
File "/usr/local/lib/python2.6/dist-packages/django/db/models/sql/query.py", line 1128, in add_q
can_reuse=used_aliases)
File "/usr/local/lib/python2.6/dist-packages/django/db/models/sql/query.py", line 1026, in add_filter
negate=negate, process_extras=process_extras)
File "/usr/local/lib/python2.6/dist-packages/django/db/models/sql/query.py", line 1179, in setup_joins
field, model, direct, m2m = opts.get_field_by_name(name)
File "/usr/local/lib/python2.6/dist-packages/django/db/models/options.py", line 291, in get_field_by_name
cache = self.init_name_map()
File "/usr/local/lib/python2.6/dist-packages/django/db/models/options.py", line 321, in init_name_map
for f, model in self.get_all_related_m2m_objects_with_model():
File "/usr/local/lib/python2.6/dist-packages/django/db/models/options.py", line 396, in get_all_related_m2m_objects_with_model
cache = self._fill_related_many_to_many_cache()
File "/usr/local/lib/python2.6/dist-packages/django/db/models/options.py", line 410, in _fill_related_many_to_many_cache
for klass in get_models():
File "/usr/local/lib/python2.6/dist-packages/django/db/models/loading.py", line 167, in get_models
self._populate()
File "/usr/local/lib/python2.6/dist-packages/django/db/models/loading.py", line 61, in _populate
self.load_app(app_name, True)
File "/usr/local/lib/python2.6/dist-packages/django/db/models/loading.py", line 76, in load_app
app_module = import_module(app_name)
File "/usr/local/lib/python2.6/dist-packages/django/utils/importlib.py", line 35, in import_module
__import__(name)
ImportError: No module named web
從早先的意見，我嘗試添加那麼回事：
import sys
sys.path.append('/home/username/django')
import logging
from django.core.management import setup_environ
from someproj import settings
setup_environ(settings)
from someproj import web
from someproj.web import models
from someproj.web.models import ItemConfiguration
但是這並沒有幫助。所以我創建了一個非常簡單的文件：
#!/usr/bin/python
import logging
import time
import sys
sys.path.append('/home/username/django')
from django.core.management import setup_environ
from someproj import settings
setup_environ(settings)
from someproj.web.models import ItemConfiguration
if __name__ == '__main__':
print sys.path
items = ItemConfiguration.objects.all()
for item in items:
print item
這個工程！這隻會讓我更加困惑。所以現在我想也許它與守護進程有關。它使用os.fork（），我不知道路徑是否仍然設置。這就是爲什麼我在/etc/bash.bashrc文件中設置$ PYTHONPATH變量的原因。
還有什麼見解嗎？我真的需要守護進程，因爲我需要一個漫長的運行過程，所以我沒有太多的選擇。
您應該顯示* actual * traceback，它會顯示錯誤發生的位置。 – 2010-10-22 08:06:33