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

66 lines
2.8 KiB
Python

from optparse import make_option
from django.core.cache.backends.db import BaseDatabaseCache
from django.core.management.base import LabelCommand, CommandError
from django.db import connections, router, transaction, models, DEFAULT_DB_ALIAS
from django.db.utils import DatabaseError
from django.utils.encoding import force_text
class Command(LabelCommand):
help = "Creates the table needed to use the SQL cache backend."
args = "<tablename>"
label = 'tablename'
option_list = LabelCommand.option_list + (
make_option('--database', action='store', dest='database',
default=DEFAULT_DB_ALIAS, help='Nominates a database onto '
'which the cache table will be installed. '
'Defaults to the "default" database.'),
)
requires_model_validation = False
def handle_label(self, tablename, **options):
db = options.get('database')
cache = BaseDatabaseCache(tablename, {})
if not router.allow_syncdb(db, cache.cache_model_class):
return
connection = connections[db]
fields = (
# "key" is a reserved word in MySQL, so use "cache_key" instead.
models.CharField(name='cache_key', max_length=255, unique=True, primary_key=True),
models.TextField(name='value'),
models.DateTimeField(name='expires', db_index=True),
)
table_output = []
index_output = []
qn = connection.ops.quote_name
for f in fields:
field_output = [qn(f.name), f.db_type(connection=connection)]
field_output.append("%sNULL" % ("NOT " if not f.null else ""))
if f.primary_key:
field_output.append("PRIMARY KEY")
elif f.unique:
field_output.append("UNIQUE")
if f.db_index:
unique = "UNIQUE " if f.unique else ""
index_output.append("CREATE %sINDEX %s ON %s (%s);" % \
(unique, qn('%s_%s' % (tablename, f.name)), qn(tablename),
qn(f.name)))
table_output.append(" ".join(field_output))
full_statement = ["CREATE TABLE %s (" % qn(tablename)]
for i, line in enumerate(table_output):
full_statement.append(' %s%s' % (line, ',' if i < len(table_output)-1 else ''))
full_statement.append(');')
with transaction.commit_on_success_unless_managed():
curs = connection.cursor()
try:
curs.execute("\n".join(full_statement))
except DatabaseError as e:
raise CommandError(
"Cache table '%s' could not be created.\nThe error was: %s." %
(tablename, force_text(e)))
for statement in index_output:
curs.execute(statement)