详解django实现自定义manage命令的扩展

import os
import sys


def main():
  os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'gaoyou.settings')
  try:
    from django.core.management import execute_from_command_line
  except ImportError as exc:
    raise ImportError(
      "Couldn't import Django. Are you sure it's installed and "
      "available on your PYTHONPATH environment variable? Did you "
      "forget to activate a virtual environment?"
    ) from exc
  execute_from_command_line(sys.argv)


if __name__ == '__main__':
  main()

python manage.py 命令名(即任意py文件名不用加.py)
#类似我们迁移数据库命令
#python manage.py makemigrations
#python manage.py migrate

django.core.management.find_management_module函数发现"管理模块":

django.core.management.find_management_module()
def find_management_module(app_name):
  """
  Determines the path to the management module for the given app_name,
  without actually importing the application or the management module.

  Raises ImportError if the management module cannot be found for any reason.
  """
  parts = app_name.split('.')
  parts.append('management')
  parts.reverse()
  part = parts.pop()
  path = None

def find_commands(management_dir):
  """
  Given a path to a management directory, returns a list of all the command
  names that are available.

  Returns an empty list if no commands are defined.
  """
  command_dir = os.path.join(management_dir, 'commands')
  try:
    return [f[:-3] for f in os.listdir(command_dir)
      if not f.startswith('_') and f.endswith('.py')]
  except OSError:
  return []

def load_command_class(app_name, name):
  """
  Given a command name and an application name, returns the Command
  class instance. All errors raised by the import process
  (ImportError, AttributeError) are allowed to propagate.
  """
  module = import_module('%s.management.commands.%s' % (app_name, name))
  return module.Command()

from django.core.management.base import BaseCommand, CommandError
from django.db import models

class Command(BaseCommand):
  help = '每日凌晨对当天数据库进行更新'

  def handle(self, *args, **options):
    print('hello world')

from django.core.management.base import BaseCommand, CommandError
from django.db import models


class Command(BaseCommand):
  help = '每日凌晨对当天数据库进行更新'

  # 接收参数
  def add_arguments(self, parser):
    parser.add_argument('offset', type=int, help='天数转移量')

  def handle(self, *args, **options):
    offset = options['offset'] # 拿到参数的值
    print(offset)
    print('hello world')
    self.stdout.write(self.style.SUCCESS('{} Successfully {}'.format('接收成功', offset))) #可以自定制在控制台输出的内容