390 lines
14 KiB
Python
390 lines
14 KiB
Python
"""
|
|
Base classes for writing management commands (named commands which can
|
|
be executed through ``django-admin.py`` or ``manage.py``).
|
|
|
|
"""
|
|
import os
|
|
import sys
|
|
|
|
from optparse import make_option, OptionParser
|
|
import traceback
|
|
|
|
import django
|
|
from django.core.exceptions import ImproperlyConfigured
|
|
from django.core.management.color import color_style
|
|
from django.utils.encoding import smart_str
|
|
from django.utils.six import StringIO
|
|
|
|
|
|
class CommandError(Exception):
|
|
"""
|
|
Exception class indicating a problem while executing a management
|
|
command.
|
|
|
|
If this exception is raised during the execution of a management
|
|
command, it will be caught and turned into a nicely-printed error
|
|
message to the appropriate output stream (i.e., stderr); as a
|
|
result, raising this exception (with a sensible description of the
|
|
error) is the preferred way to indicate that something has gone
|
|
wrong in the execution of a command.
|
|
|
|
"""
|
|
pass
|
|
|
|
|
|
def handle_default_options(options):
|
|
"""
|
|
Include any default options that all commands should accept here
|
|
so that ManagementUtility can handle them before searching for
|
|
user commands.
|
|
|
|
"""
|
|
if options.settings:
|
|
os.environ['DJANGO_SETTINGS_MODULE'] = options.settings
|
|
if options.pythonpath:
|
|
sys.path.insert(0, options.pythonpath)
|
|
|
|
|
|
class OutputWrapper(object):
|
|
"""
|
|
Wrapper around stdout/stderr
|
|
"""
|
|
def __init__(self, out, style_func=None, ending='\n'):
|
|
self._out = out
|
|
self.style_func = None
|
|
if hasattr(out, 'isatty') and out.isatty():
|
|
self.style_func = style_func
|
|
self.ending = ending
|
|
|
|
def __getattr__(self, name):
|
|
return getattr(self._out, name)
|
|
|
|
def write(self, msg, style_func=None, ending=None):
|
|
ending = ending is None and self.ending or ending
|
|
if ending and not msg.endswith(ending):
|
|
msg += ending
|
|
style_func = [f for f in (style_func, self.style_func, lambda x:x)
|
|
if f is not None][0]
|
|
self._out.write(smart_str(style_func(msg)))
|
|
|
|
|
|
class BaseCommand(object):
|
|
"""
|
|
The base class from which all management commands ultimately
|
|
derive.
|
|
|
|
Use this class if you want access to all of the mechanisms which
|
|
parse the command-line arguments and work out what code to call in
|
|
response; if you don't need to change any of that behavior,
|
|
consider using one of the subclasses defined in this file.
|
|
|
|
If you are interested in overriding/customizing various aspects of
|
|
the command-parsing and -execution behavior, the normal flow works
|
|
as follows:
|
|
|
|
1. ``django-admin.py`` or ``manage.py`` loads the command class
|
|
and calls its ``run_from_argv()`` method.
|
|
|
|
2. The ``run_from_argv()`` method calls ``create_parser()`` to get
|
|
an ``OptionParser`` for the arguments, parses them, performs
|
|
any environment changes requested by options like
|
|
``pythonpath``, and then calls the ``execute()`` method,
|
|
passing the parsed arguments.
|
|
|
|
3. The ``execute()`` method attempts to carry out the command by
|
|
calling the ``handle()`` method with the parsed arguments; any
|
|
output produced by ``handle()`` will be printed to standard
|
|
output and, if the command is intended to produce a block of
|
|
SQL statements, will be wrapped in ``BEGIN`` and ``COMMIT``.
|
|
|
|
4. If ``handle()`` or ``execute()`` raised any exception (e.g.
|
|
``CommandError``), ``run_from_argv()`` will instead print an error
|
|
message to ``stderr``.
|
|
|
|
Thus, the ``handle()`` method is typically the starting point for
|
|
subclasses; many built-in commands and command types either place
|
|
all of their logic in ``handle()``, or perform some additional
|
|
parsing work in ``handle()`` and then delegate from it to more
|
|
specialized methods as needed.
|
|
|
|
Several attributes affect behavior at various steps along the way:
|
|
|
|
``args``
|
|
A string listing the arguments accepted by the command,
|
|
suitable for use in help messages; e.g., a command which takes
|
|
a list of application names might set this to '<appname
|
|
appname ...>'.
|
|
|
|
``can_import_settings``
|
|
A boolean indicating whether the command needs to be able to
|
|
import Django settings; if ``True``, ``execute()`` will verify
|
|
that this is possible before proceeding. Default value is
|
|
``True``.
|
|
|
|
``help``
|
|
A short description of the command, which will be printed in
|
|
help messages.
|
|
|
|
``option_list``
|
|
This is the list of ``optparse`` options which will be fed
|
|
into the command's ``OptionParser`` for parsing arguments.
|
|
|
|
``output_transaction``
|
|
A boolean indicating whether the command outputs SQL
|
|
statements; if ``True``, the output will automatically be
|
|
wrapped with ``BEGIN;`` and ``COMMIT;``. Default value is
|
|
``False``.
|
|
|
|
``requires_model_validation``
|
|
A boolean; if ``True``, validation of installed models will be
|
|
performed prior to executing the command. Default value is
|
|
``True``. To validate an individual application's models
|
|
rather than all applications' models, call
|
|
``self.validate(app)`` from ``handle()``, where ``app`` is the
|
|
application's Python module.
|
|
|
|
"""
|
|
# Metadata about this command.
|
|
option_list = (
|
|
make_option('-v', '--verbosity', action='store', dest='verbosity', default='1',
|
|
type='choice', choices=['0', '1', '2', '3'],
|
|
help='Verbosity level; 0=minimal output, 1=normal output, 2=verbose output, 3=very verbose output'),
|
|
make_option('--settings',
|
|
help='The Python path to a settings module, e.g. "myproject.settings.main". If this isn\'t provided, the DJANGO_SETTINGS_MODULE environment variable will be used.'),
|
|
make_option('--pythonpath',
|
|
help='A directory to add to the Python path, e.g. "/home/djangoprojects/myproject".'),
|
|
make_option('--traceback', action='store_true',
|
|
help='Print traceback on exception'),
|
|
)
|
|
help = ''
|
|
args = ''
|
|
|
|
# Configuration shortcuts that alter various logic.
|
|
can_import_settings = True
|
|
requires_model_validation = True
|
|
output_transaction = False # Whether to wrap the output in a "BEGIN; COMMIT;"
|
|
|
|
def __init__(self):
|
|
self.style = color_style()
|
|
|
|
def get_version(self):
|
|
"""
|
|
Return the Django version, which should be correct for all
|
|
built-in Django commands. User-supplied commands should
|
|
override this method.
|
|
|
|
"""
|
|
return django.get_version()
|
|
|
|
def usage(self, subcommand):
|
|
"""
|
|
Return a brief description of how to use this command, by
|
|
default from the attribute ``self.help``.
|
|
|
|
"""
|
|
usage = '%%prog %s [options] %s' % (subcommand, self.args)
|
|
if self.help:
|
|
return '%s\n\n%s' % (usage, self.help)
|
|
else:
|
|
return usage
|
|
|
|
def create_parser(self, prog_name, subcommand):
|
|
"""
|
|
Create and return the ``OptionParser`` which will be used to
|
|
parse the arguments to this command.
|
|
|
|
"""
|
|
return OptionParser(prog=prog_name,
|
|
usage=self.usage(subcommand),
|
|
version=self.get_version(),
|
|
option_list=self.option_list)
|
|
|
|
def print_help(self, prog_name, subcommand):
|
|
"""
|
|
Print the help message for this command, derived from
|
|
``self.usage()``.
|
|
|
|
"""
|
|
parser = self.create_parser(prog_name, subcommand)
|
|
parser.print_help()
|
|
|
|
def run_from_argv(self, argv):
|
|
"""
|
|
Set up any environment changes requested (e.g., Python path
|
|
and Django settings), then run this command. If the
|
|
command raises a ``CommandError``, intercept it and print it sensibly
|
|
to stderr.
|
|
"""
|
|
parser = self.create_parser(argv[0], argv[1])
|
|
options, args = parser.parse_args(argv[2:])
|
|
handle_default_options(options)
|
|
try:
|
|
self.execute(*args, **options.__dict__)
|
|
except Exception as e:
|
|
if options.traceback:
|
|
self.stderr.write(traceback.format_exc())
|
|
self.stderr.write('%s: %s' % (e.__class__.__name__, e))
|
|
sys.exit(1)
|
|
|
|
def execute(self, *args, **options):
|
|
"""
|
|
Try to execute this command, performing model validation if
|
|
needed (as controlled by the attribute
|
|
``self.requires_model_validation``, except if force-skipped).
|
|
"""
|
|
|
|
# Switch to English, because django-admin.py creates database content
|
|
# like permissions, and those shouldn't contain any translations.
|
|
# But only do this if we can assume we have a working settings file,
|
|
# because django.utils.translation requires settings.
|
|
saved_lang = None
|
|
self.stdout = OutputWrapper(options.get('stdout', sys.stdout))
|
|
self.stderr = OutputWrapper(options.get('stderr', sys.stderr), self.style.ERROR)
|
|
|
|
if self.can_import_settings:
|
|
from django.utils import translation
|
|
saved_lang = translation.get_language()
|
|
translation.activate('en-us')
|
|
|
|
try:
|
|
if self.requires_model_validation and not options.get('skip_validation'):
|
|
self.validate()
|
|
output = self.handle(*args, **options)
|
|
if output:
|
|
if self.output_transaction:
|
|
# This needs to be imported here, because it relies on
|
|
# settings.
|
|
from django.db import connections, DEFAULT_DB_ALIAS
|
|
connection = connections[options.get('database', DEFAULT_DB_ALIAS)]
|
|
if connection.ops.start_transaction_sql():
|
|
self.stdout.write(self.style.SQL_KEYWORD(connection.ops.start_transaction_sql()))
|
|
self.stdout.write(output)
|
|
if self.output_transaction:
|
|
self.stdout.write('\n' + self.style.SQL_KEYWORD("COMMIT;"))
|
|
finally:
|
|
if saved_lang is not None:
|
|
translation.activate(saved_lang)
|
|
|
|
def validate(self, app=None, display_num_errors=False):
|
|
"""
|
|
Validates the given app, raising CommandError for any errors.
|
|
|
|
If app is None, then this will validate all installed apps.
|
|
|
|
"""
|
|
from django.core.management.validation import get_validation_errors
|
|
s = StringIO()
|
|
num_errors = get_validation_errors(s, app)
|
|
if num_errors:
|
|
s.seek(0)
|
|
error_text = s.read()
|
|
raise CommandError("One or more models did not validate:\n%s" % error_text)
|
|
if display_num_errors:
|
|
self.stdout.write("%s error%s found" % (num_errors, num_errors != 1 and 's' or ''))
|
|
|
|
def handle(self, *args, **options):
|
|
"""
|
|
The actual logic of the command. Subclasses must implement
|
|
this method.
|
|
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
|
|
class AppCommand(BaseCommand):
|
|
"""
|
|
A management command which takes one or more installed application
|
|
names as arguments, and does something with each of them.
|
|
|
|
Rather than implementing ``handle()``, subclasses must implement
|
|
``handle_app()``, which will be called once for each application.
|
|
|
|
"""
|
|
args = '<appname appname ...>'
|
|
|
|
def handle(self, *app_labels, **options):
|
|
from django.db import models
|
|
if not app_labels:
|
|
raise CommandError('Enter at least one appname.')
|
|
try:
|
|
app_list = [models.get_app(app_label) for app_label in app_labels]
|
|
except (ImproperlyConfigured, ImportError) as e:
|
|
raise CommandError("%s. Are you sure your INSTALLED_APPS setting is correct?" % e)
|
|
output = []
|
|
for app in app_list:
|
|
app_output = self.handle_app(app, **options)
|
|
if app_output:
|
|
output.append(app_output)
|
|
return '\n'.join(output)
|
|
|
|
def handle_app(self, app, **options):
|
|
"""
|
|
Perform the command's actions for ``app``, which will be the
|
|
Python module corresponding to an application name given on
|
|
the command line.
|
|
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
|
|
class LabelCommand(BaseCommand):
|
|
"""
|
|
A management command which takes one or more arbitrary arguments
|
|
(labels) on the command line, and does something with each of
|
|
them.
|
|
|
|
Rather than implementing ``handle()``, subclasses must implement
|
|
``handle_label()``, which will be called once for each label.
|
|
|
|
If the arguments should be names of installed applications, use
|
|
``AppCommand`` instead.
|
|
|
|
"""
|
|
args = '<label label ...>'
|
|
label = 'label'
|
|
|
|
def handle(self, *labels, **options):
|
|
if not labels:
|
|
raise CommandError('Enter at least one %s.' % self.label)
|
|
|
|
output = []
|
|
for label in labels:
|
|
label_output = self.handle_label(label, **options)
|
|
if label_output:
|
|
output.append(label_output)
|
|
return '\n'.join(output)
|
|
|
|
def handle_label(self, label, **options):
|
|
"""
|
|
Perform the command's actions for ``label``, which will be the
|
|
string as given on the command line.
|
|
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
|
|
class NoArgsCommand(BaseCommand):
|
|
"""
|
|
A command which takes no arguments on the command line.
|
|
|
|
Rather than implementing ``handle()``, subclasses must implement
|
|
``handle_noargs()``; ``handle()`` itself is overridden to ensure
|
|
no arguments are passed to the command.
|
|
|
|
Attempting to pass arguments will raise ``CommandError``.
|
|
|
|
"""
|
|
args = ''
|
|
|
|
def handle(self, *args, **options):
|
|
if args:
|
|
raise CommandError("Command doesn't accept any arguments")
|
|
return self.handle_noargs(**options)
|
|
|
|
def handle_noargs(self, **options):
|
|
"""
|
|
Perform this command's actions.
|
|
|
|
"""
|
|
raise NotImplementedError()
|