django1/django/core/management/sql.py

185 lines
7.8 KiB
Python

import os
import re
from django.conf import settings
from django.core.management.base import CommandError
from django.db import models
from django.db.models import get_models
def sql_create(app, style, connection):
"Returns a list of the CREATE TABLE SQL statements for the given app."
if connection.settings_dict['ENGINE'] == 'django.db.backends.dummy':
# This must be the "dummy" database backend, which means the user
# hasn't set ENGINE for the databse.
raise CommandError("Django doesn't know which syntax to use for your SQL statements,\n" +
"because you haven't specified the ENGINE setting for the database.\n" +
"Edit your settings file and change DATBASES['default']['ENGINE'] to something like\n" +
"'django.db.backends.postgresql' or 'django.db.backends.mysql'.")
# Get installed models, so we generate REFERENCES right.
# We trim models from the current app so that the sqlreset command does not
# generate invalid SQL (leaving models out of known_models is harmless, so
# we can be conservative).
app_models = models.get_models(app, include_auto_created=True)
final_output = []
tables = connection.introspection.table_names()
known_models = set([model for model in connection.introspection.installed_models(tables) if model not in app_models])
pending_references = {}
for model in app_models:
output, references = connection.creation.sql_create_model(model, style, known_models)
final_output.extend(output)
for refto, refs in references.items():
pending_references.setdefault(refto, []).extend(refs)
if refto in known_models:
final_output.extend(connection.creation.sql_for_pending_references(refto, style, pending_references))
final_output.extend(connection.creation.sql_for_pending_references(model, style, pending_references))
# Keep track of the fact that we've created the table for this model.
known_models.add(model)
# Handle references to tables that are from other apps
# but don't exist physically.
not_installed_models = set(pending_references.keys())
if not_installed_models:
alter_sql = []
for model in not_installed_models:
alter_sql.extend(['-- ' + sql for sql in
connection.creation.sql_for_pending_references(model, style, pending_references)])
if alter_sql:
final_output.append('-- The following references should be added but depend on non-existent tables:')
final_output.extend(alter_sql)
return final_output
def sql_delete(app, style, connection):
"Returns a list of the DROP TABLE SQL statements for the given app."
# This should work even if a connection isn't available
try:
cursor = connection.cursor()
except:
cursor = None
# Figure out which tables already exist
if cursor:
table_names = connection.introspection.get_table_list(cursor)
else:
table_names = []
output = []
# Output DROP TABLE statements for standard application tables.
to_delete = set()
references_to_delete = {}
app_models = models.get_models(app, include_auto_created=True)
for model in app_models:
if cursor and connection.introspection.table_name_converter(model._meta.db_table) in table_names:
# The table exists, so it needs to be dropped
opts = model._meta
for f in opts.local_fields:
if f.rel and f.rel.to not in to_delete:
references_to_delete.setdefault(f.rel.to, []).append( (model, f) )
to_delete.add(model)
for model in app_models:
if connection.introspection.table_name_converter(model._meta.db_table) in table_names:
output.extend(connection.creation.sql_destroy_model(model, references_to_delete, style))
# Close database connection explicitly, in case this output is being piped
# directly into a database client, to avoid locking issues.
if cursor:
cursor.close()
connection.close()
return output[::-1] # Reverse it, to deal with table dependencies.
def sql_reset(app, style, connection):
"Returns a list of the DROP TABLE SQL, then the CREATE TABLE SQL, for the given module."
return sql_delete(app, style, connection) + sql_all(app, style, connection)
def sql_flush(style, connection, only_django=False):
"""
Returns a list of the SQL statements used to flush the database.
If only_django is True, then only table names that have associated Django
models and are in INSTALLED_APPS will be included.
"""
if only_django:
tables = connection.introspection.django_table_names(only_existing=True)
else:
tables = connection.introspection.table_names()
statements = connection.ops.sql_flush(
style, tables, connection.introspection.sequence_list()
)
return statements
def sql_custom(app, style, connection):
"Returns a list of the custom table modifying SQL statements for the given app."
output = []
app_models = get_models(app)
app_dir = os.path.normpath(os.path.join(os.path.dirname(app.__file__), 'sql'))
for model in app_models:
output.extend(custom_sql_for_model(model, style, connection))
return output
def sql_indexes(app, style, connection):
"Returns a list of the CREATE INDEX SQL statements for all models in the given app."
output = []
for model in models.get_models(app):
output.extend(connection.creation.sql_indexes_for_model(model, style))
return output
def sql_all(app, style, connection):
"Returns a list of CREATE TABLE SQL, initial-data inserts, and CREATE INDEX SQL for the given module."
return sql_create(app, style, connection) + sql_custom(app, style, connection) + sql_indexes(app, style, connection)
def custom_sql_for_model(model, style, connection):
opts = model._meta
app_dir = os.path.normpath(os.path.join(os.path.dirname(models.get_app(model._meta.app_label).__file__), 'sql'))
output = []
# Post-creation SQL should come before any initial SQL data is loaded.
# However, this should not be done for models that are unmanaged or
# for fields that are part of a parent model (via model inheritance).
if opts.managed:
post_sql_fields = [f for f in opts.local_fields if hasattr(f, 'post_create_sql')]
for f in post_sql_fields:
output.extend(f.post_create_sql(style, model._meta.db_table))
# Some backends can't execute more than one SQL statement at a time,
# so split into separate statements.
statements = re.compile(r";[ \t]*$", re.M)
# Find custom SQL, if it's available.
backend_name = connection.settings_dict['ENGINE'].split('.')[-1]
sql_files = [os.path.join(app_dir, "%s.%s.sql" % (opts.object_name.lower(), backend_name)),
os.path.join(app_dir, "%s.sql" % opts.object_name.lower())]
for sql_file in sql_files:
if os.path.exists(sql_file):
fp = open(sql_file, 'U')
for statement in statements.split(fp.read().decode(settings.FILE_CHARSET)):
# Remove any comments from the file
statement = re.sub(ur"--.*([\n\Z]|$)", "", statement)
if statement.strip():
output.append(statement + u";")
fp.close()
return output
def emit_post_sync_signal(created_models, verbosity, interactive, db):
# Emit the post_sync signal for every application.
for app in models.get_apps():
app_name = app.__name__.split('.')[-2]
if verbosity >= 2:
print "Running post-sync handlers for application", app_name
models.signals.post_syncdb.send(sender=app, app=app,
created_models=created_models, verbosity=verbosity,
interactive=interactive, db=db)