Django中的一個app應用，實際上就是相當于一個包

最好將一個應用的相關文件（包括模板、靜態文件）放在一起，以便用于其它的項目

Django中將app以包（package）的形式重復利用

• 打包app

  1. 創建新的目錄（如django-polls）以存放app（注意該目錄名不應該同其它package名相同）
  2. 將polls文件拷入django-polls文件中
  3. 在django-polls文件夾下創建README.rst文件

  =====
  Polls
  =====
  
  Polls is a simple Django app to conduct Web-based polls. For each question, visitors can choose between a fixed number of answers.
  
  Detailed documentation is in the "docs" directory.
  
  Quick start
  -----------
  
  1. Add "polls" to your INSTALLED_APPS setting like this::
  
      INSTALLED_APPS = [
          ...
          'polls',
      ]
  
  2. Include the polls URLconf in your project urls.py like this::
  
      url(r'^polls/', include('polls.urls')),
  
  3. Run `python manage.py migrate` to create the polls models.
  
  4. Start the development server and visit http://127.0.0.1:8000/admin/
     to create a poll (you'll need the Admin app enabled).
  
  5. Visit http://127.0.0.1:8000/polls/ to participate in the poll.
  

  4. 創建LICENSE文件（許可文件）
  5. 創建安裝文件setup.py（setuptools文檔）

  import os
  from setuptools import find_packages, setup
  
  with open(os.path.join(os.path.dirname(__file__), 'README.rst')) as readme:
      README = readme.read()
  
  # allow setup.py to be run from any path
  os.chdir(os.path.normpath(os.path.join(os.path.abspath(__file__), os.pardir)))
  
  setup(
      name='django-polls',
      version='0.1',
      packages=find_packages(),
      include_package_data=True,
      license='BSD License',  # example license
      description='A simple Django app to conduct Web-based polls.',
      long_description=README,
      url='https://www.example.com/',
      author='Your Name',
      author_email='yourname@example.com',
      classifiers=[
          'Environment :: Web Environment',
          'Framework :: Django',
          'Framework :: Django :: X.Y',  # replace "X.Y" as appropriate
          'Intended Audience :: Developers',
          'License :: OSI Approved :: BSD License',  # example license
          'Operating System :: OS Independent',
          'Programming Language :: Python',
          # Replace these appropriately if you are stuck on Python 2.
          'Programming Language :: Python :: 3',
          'Programming Language :: Python :: 3.4',
          'Programming Language :: Python :: 3.5',
          'Topic :: Internet :: WWW/HTTP',
          'Topic :: Internet :: WWW/HTTP :: Dynamic Content',
      ],
  )
  

  6. 創建MANIFEST.in文件
     默認情況下，將創建的包中只會包含與python相關的模塊和包，為了將一些其它文件（如templates/、README.rst、LICENSE）也包含進新創建的包中，需要在MANIFEST.in文件中進行指定

  include LICENSE
  include README.rst
  recursive-include polls/static *
  recursive-include polls/templates *
  

  7. （可選）在新創建的app中包含細節描述文件
     創建docs文件夾，并在MANIFEST.in文件中添加一句

  recursive-inclued docs *
  

  8. 創建包
     在命令提示符中輸入

  > python setup.py sdist
  

  創建的包位于新建的dist文件夾中，名稱為django-polls-0.1.tar.gz

• 使用應用包

  1. 安裝該app包（最好在虛擬環境下）

  pip install --user django-polls/dist/django-polls-0.1.tar.gz
  # 注意是自己的相對路徑
  

  2. 現在就可以使用該app了（可以刪去原項目中的polls文件了）
  3. 卸載包

  pip uninstall django-polls