django源码分析 python ma

#!/usr/bin/env python
import os
import sys

if __name__ == "__main__":
    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "order.settings")
    try:
        from django.core.management import execute_from_command_line
    except ImportError:
        # The above import may fail for some other reason. Ensure that the
        # issue is really that Django is missing to avoid masking other
        # exceptions on Python 2.
        try:
            import django
        except ImportError:
            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?"
            )
        raise
    execute_from_command_line(sys.argv)

def execute_from_command_line(argv=None):
    """
    A simple method that runs a ManagementUtility.
    """
    utility = ManagementUtility(argv)
    utility.execute()

execute方法中的部分代码
...
if settings.configured:
    # Start the auto-reloading dev server even if the code is broken.
    # The hardcoded condition is a code smell but we can't rely on a
    # flag on the command class because we haven't located it yet.
    if subcommand == 'runserver' and '--noreload' not in self.argv:
        try:
            autoreload.check_errors(django.setup)()
        except Exception:
            # The exception will be raised later in the child process
            # started by the autoreloader. Pretend it didn't happen by
            # loading an empty list of applications.
            apps.all_models = defaultdict(OrderedDict)
            apps.app_configs = OrderedDict()
            apps.apps_ready = apps.models_ready = apps.ready = True
...

execute方法中的部分代码
...
elif self.argv[1:] in (['--help'], ['-h']):
    sys.stdout.write(self.main_help_text() + '\n')
else:
    self.fetch_command(subcommand).run_from_argv(self.argv)
...

BaseCommand类中run_from_argv方法的部分代码
...
try:
    self.execute(*args, **cmd_options)
except Exception as e:
    if options.traceback or not isinstance(e, CommandError):
        raise
...

RunserverCommand类里面的handle方法部分代码

def handle(self, *args, **options):
　　...
if not self.addr:
        self.addr = '::1' if self.use_ipv6 else '127.0.0.1'
        self._raw_ipv6 = self.use_ipv6
    self.run(**options)

RunserverCommand中的部分代码
def run(self, **options):
    """
    Runs the server, using the autoreloader if needed
    """
    use_reloader = options['use_reloader']

    if use_reloader:
        autoreload.main(self.inner_run, None, options)
    else:
        self.inner_run(None, **options)

def inner_run(self, *args, **options):
    ...

    try:
        handler = self.get_handler(*args, **options)
        run(self.addr, int(self.port), handler,
            ipv6=self.use_ipv6, threading=threading, server_cls=self.server_cls)
    except Socket.error as e:
    
    ...