django1/django/core/management/commands/shell.py

103 lines
4.0 KiB
Python

import os
import select
import sys
import traceback
from django.core.management import BaseCommand, CommandError
from django.utils.datastructures import OrderedSet
class Command(BaseCommand):
help = (
"Runs a Python interactive interpreter. Tries to use IPython or "
"bpython, if one of them is available. Any standard input is executed "
"as code."
)
requires_system_checks = False
shells = ['ipython', 'bpython', 'python']
def add_arguments(self, parser):
parser.add_argument(
'--no-startup', action='store_true', dest='no_startup',
help='When using plain Python, ignore the PYTHONSTARTUP environment variable and ~/.pythonrc.py script.',
)
parser.add_argument(
'-i', '--interface', choices=self.shells, dest='interface',
help='Specify an interactive interpreter interface. Available options: "ipython", "bpython", and "python"',
)
parser.add_argument(
'-c', '--command', dest='command',
help='Instead of opening an interactive shell, run a command as Django and exit.',
)
def ipython(self, options):
from IPython import start_ipython
start_ipython(argv=[])
def bpython(self, options):
import bpython
bpython.embed()
def python(self, options):
import code
# Set up a dictionary to serve as the environment for the shell, so
# that tab completion works on objects that are imported at runtime.
imported_objects = {}
try: # Try activating rlcompleter, because it's handy.
import readline
except ImportError:
pass
else:
# We don't have to wrap the following import in a 'try', because
# we already know 'readline' was imported successfully.
import rlcompleter
readline.set_completer(rlcompleter.Completer(imported_objects).complete)
# Enable tab completion on systems using libedit (e.g. macOS).
# These lines are copied from Python's Lib/site.py.
readline_doc = getattr(readline, '__doc__', '')
if readline_doc is not None and 'libedit' in readline_doc:
readline.parse_and_bind("bind ^I rl_complete")
else:
readline.parse_and_bind("tab:complete")
# We want to honor both $PYTHONSTARTUP and .pythonrc.py, so follow system
# conventions and get $PYTHONSTARTUP first then .pythonrc.py.
if not options['no_startup']:
for pythonrc in OrderedSet([os.environ.get("PYTHONSTARTUP"), os.path.expanduser('~/.pythonrc.py')]):
if not pythonrc:
continue
if not os.path.isfile(pythonrc):
continue
with open(pythonrc) as handle:
pythonrc_code = handle.read()
# Match the behavior of the cpython shell where an error in
# PYTHONSTARTUP prints an exception and continues.
try:
exec(compile(pythonrc_code, pythonrc, 'exec'), imported_objects)
except Exception:
traceback.print_exc()
code.interact(local=imported_objects)
def handle(self, **options):
# Execute the command and exit.
if options['command']:
exec(options['command'])
return
# Execute stdin if it has anything to read and exit.
# Not supported on Windows due to select.select() limitations.
if sys.platform != 'win32' and select.select([sys.stdin], [], [], 0)[0]:
exec(sys.stdin.read())
return
available_shells = [options['interface']] if options['interface'] else self.shells
for shell in available_shells:
try:
return getattr(self, shell)(options)
except ImportError:
pass
raise CommandError("Couldn't import {} interface.".format(shell))