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

293 lines
14 KiB
Python

# -*- coding: utf-8 -*-
from __future__ import unicode_literals
import time
import warnings
from collections import OrderedDict
from importlib import import_module
from django.apps import apps
from django.core.management import call_command
from django.core.management.base import BaseCommand, CommandError
from django.core.management.sql import (
emit_post_migrate_signal, emit_pre_migrate_signal,
)
from django.db import DEFAULT_DB_ALIAS, connections, router, transaction
from django.db.migrations.autodetector import MigrationAutodetector
from django.db.migrations.executor import MigrationExecutor
from django.db.migrations.loader import AmbiguityError
from django.db.migrations.state import ProjectState
from django.utils.deprecation import RemovedInDjango20Warning
from django.utils.module_loading import module_has_submodule
class Command(BaseCommand):
help = "Updates database schema. Manages both apps with migrations and those without."
def add_arguments(self, parser):
parser.add_argument('app_label', nargs='?',
help='App label of an application to synchronize the state.')
parser.add_argument('migration_name', nargs='?',
help=(
'Database state will be brought to the state after that '
'migration. Use the name "zero" to unapply all migrations.'
),
)
parser.add_argument('--noinput', action='store_false', dest='interactive', default=True,
help='Tells Django to NOT prompt the user for input of any kind.')
parser.add_argument('--database', action='store', dest='database',
default=DEFAULT_DB_ALIAS, help='Nominates a database to synchronize. '
'Defaults to the "default" database.')
parser.add_argument('--fake', action='store_true', dest='fake', default=False,
help='Mark migrations as run without actually running them.')
parser.add_argument('--fake-initial', action='store_true', dest='fake_initial', default=False,
help='Detect if tables already exist and fake-apply initial migrations if so. Make sure '
'that the current database schema matches your initial migration before using this '
'flag. Django will only check for an existing table name.')
parser.add_argument('--list', '-l', action='store_true', dest='list', default=False,
help='Show a list of all known migrations and which are applied.')
def handle(self, *args, **options):
self.verbosity = options.get('verbosity')
self.interactive = options.get('interactive')
# Import the 'management' module within each installed app, to register
# dispatcher events.
for app_config in apps.get_app_configs():
if module_has_submodule(app_config.module, "management"):
import_module('.management', app_config.name)
# Get the database we're operating from
db = options.get('database')
connection = connections[db]
# If they asked for a migration listing, quit main execution flow and show it
if options.get("list", False):
warnings.warn(
"The 'migrate --list' command is deprecated. Use 'showmigrations' instead.",
RemovedInDjango20Warning, stacklevel=2)
self.stdout.ending = None # Remove when #21429 is fixed
return call_command(
'showmigrations',
'--list',
app_labels=[options['app_label']] if options['app_label'] else None,
database=db,
no_color=options.get('no_color'),
settings=options.get('settings'),
stdout=self.stdout,
traceback=options.get('traceback'),
verbosity=self.verbosity,
)
# Hook for backends needing any database preparation
connection.prepare_database()
# Work out which apps have migrations and which do not
executor = MigrationExecutor(connection, self.migration_progress_callback)
# Before anything else, see if there's conflicting apps and drop out
# hard if there are any
conflicts = executor.loader.detect_conflicts()
if conflicts:
name_str = "; ".join(
"%s in %s" % (", ".join(names), app)
for app, names in conflicts.items()
)
raise CommandError(
"Conflicting migrations detected (%s).\nTo fix them run "
"'python manage.py makemigrations --merge'" % name_str
)
# If they supplied command line arguments, work out what they mean.
target_app_labels_only = True
if options['app_label'] and options['migration_name']:
app_label, migration_name = options['app_label'], options['migration_name']
if app_label not in executor.loader.migrated_apps:
raise CommandError(
"App '%s' does not have migrations." % app_label
)
if migration_name == "zero":
targets = [(app_label, None)]
else:
try:
migration = executor.loader.get_migration_by_prefix(app_label, migration_name)
except AmbiguityError:
raise CommandError(
"More than one migration matches '%s' in app '%s'. "
"Please be more specific." %
(migration_name, app_label)
)
except KeyError:
raise CommandError("Cannot find a migration matching '%s' from app '%s'." % (
migration_name, app_label))
targets = [(app_label, migration.name)]
target_app_labels_only = False
elif options['app_label']:
app_label = options['app_label']
if app_label not in executor.loader.migrated_apps:
raise CommandError(
"App '%s' does not have migrations." % app_label
)
targets = [key for key in executor.loader.graph.leaf_nodes() if key[0] == app_label]
else:
targets = executor.loader.graph.leaf_nodes()
plan = executor.migration_plan(targets)
run_syncdb = options.get('run_syncdb') and executor.loader.unmigrated_apps
# Print some useful info
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Operations to perform:"))
if run_syncdb:
self.stdout.write(
self.style.MIGRATE_LABEL(" Synchronize unmigrated apps: ") +
(", ".join(executor.loader.unmigrated_apps))
)
if target_app_labels_only:
self.stdout.write(
self.style.MIGRATE_LABEL(" Apply all migrations: ") +
(", ".join(set(a for a, n in targets)) or "(none)")
)
else:
if targets[0][1] is None:
self.stdout.write(self.style.MIGRATE_LABEL(
" Unapply all migrations: ") + "%s" % (targets[0][0], )
)
else:
self.stdout.write(self.style.MIGRATE_LABEL(
" Target specific migration: ") + "%s, from %s"
% (targets[0][1], targets[0][0])
)
emit_pre_migrate_signal(self.verbosity, self.interactive, connection.alias)
# Run the syncdb phase.
if run_syncdb:
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Synchronizing apps without migrations:"))
self.sync_apps(connection, executor.loader.unmigrated_apps)
# Migrate!
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Running migrations:"))
if not plan:
if self.verbosity >= 1:
self.stdout.write(" No migrations to apply.")
# If there's changes that aren't in migrations yet, tell them how to fix it.
autodetector = MigrationAutodetector(
executor.loader.project_state(),
ProjectState.from_apps(apps),
)
changes = autodetector.changes(graph=executor.loader.graph)
if changes:
self.stdout.write(self.style.NOTICE(
" Your models have changes that are not yet reflected "
"in a migration, and so won't be applied."
))
self.stdout.write(self.style.NOTICE(
" Run 'manage.py makemigrations' to make new "
"migrations, and then re-run 'manage.py migrate' to "
"apply them."
))
else:
fake = options.get("fake")
fake_initial = options.get("fake_initial")
executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
# Send the post_migrate signal, so individual apps can do whatever they need
# to do at this point.
emit_post_migrate_signal(self.verbosity, self.interactive, connection.alias)
def migration_progress_callback(self, action, migration=None, fake=False):
if self.verbosity >= 1:
compute_time = self.verbosity > 1
if action == "apply_start":
if compute_time:
self.start = time.time()
self.stdout.write(" Applying %s..." % migration, ending="")
self.stdout.flush()
elif action == "apply_success":
elapsed = " (%.3fs)" % (time.time() - self.start) if compute_time else ""
if fake:
self.stdout.write(self.style.MIGRATE_SUCCESS(" FAKED" + elapsed))
else:
self.stdout.write(self.style.MIGRATE_SUCCESS(" OK" + elapsed))
elif action == "unapply_start":
if compute_time:
self.start = time.time()
self.stdout.write(" Unapplying %s..." % migration, ending="")
self.stdout.flush()
elif action == "unapply_success":
elapsed = " (%.3fs)" % (time.time() - self.start) if compute_time else ""
if fake:
self.stdout.write(self.style.MIGRATE_SUCCESS(" FAKED" + elapsed))
else:
self.stdout.write(self.style.MIGRATE_SUCCESS(" OK" + elapsed))
elif action == "render_start":
if compute_time:
self.start = time.time()
self.stdout.write(" Rendering model states...", ending="")
self.stdout.flush()
elif action == "render_success":
elapsed = " (%.3fs)" % (time.time() - self.start) if compute_time else ""
self.stdout.write(self.style.MIGRATE_SUCCESS(" DONE" + elapsed))
def sync_apps(self, connection, app_labels):
"Runs the old syncdb-style operation on a list of app_labels."
cursor = connection.cursor()
try:
# Get a list of already installed *models* so that references work right.
tables = connection.introspection.table_names(cursor)
created_models = set()
# Build the manifest of apps and models that are to be synchronized
all_models = [
(app_config.label,
router.get_migratable_models(app_config, connection.alias, include_auto_created=False))
for app_config in apps.get_app_configs()
if app_config.models_module is not None and app_config.label in app_labels
]
def model_installed(model):
opts = model._meta
converter = connection.introspection.table_name_converter
# Note that if a model is unmanaged we short-circuit and never try to install it
return not ((converter(opts.db_table) in tables) or
(opts.auto_created and converter(opts.auto_created._meta.db_table) in tables))
manifest = OrderedDict(
(app_name, list(filter(model_installed, model_list)))
for app_name, model_list in all_models
)
# Create the tables for each model
if self.verbosity >= 1:
self.stdout.write(" Creating tables...\n")
with transaction.atomic(using=connection.alias, savepoint=connection.features.can_rollback_ddl):
deferred_sql = []
for app_name, model_list in manifest.items():
for model in model_list:
if not model._meta.can_migrate(connection):
continue
if self.verbosity >= 3:
self.stdout.write(
" Processing %s.%s model\n" % (app_name, model._meta.object_name)
)
with connection.schema_editor() as editor:
if self.verbosity >= 1:
self.stdout.write(" Creating table %s\n" % model._meta.db_table)
editor.create_model(model)
deferred_sql.extend(editor.deferred_sql)
editor.deferred_sql = []
created_models.add(model)
if self.verbosity >= 1:
self.stdout.write(" Running deferred SQL...\n")
for statement in deferred_sql:
cursor.execute(statement)
finally:
cursor.close()
return created_models