aerich/aerich/ddl/mysql/__init__.py
2024-06-05 23:37:30 +08:00

64 lines
3.1 KiB
Python

from typing import TYPE_CHECKING, List, Type
from tortoise.backends.mysql.schema_generator import MySQLSchemaGenerator
from aerich.ddl import BaseDDL
if TYPE_CHECKING:
from tortoise import Model # noqa:F401
class MysqlDDL(BaseDDL):
schema_generator_cls = MySQLSchemaGenerator
DIALECT = MySQLSchemaGenerator.DIALECT
_DROP_TABLE_TEMPLATE = "DROP TABLE IF EXISTS `{table_name}`"
_ADD_COLUMN_TEMPLATE = "ALTER TABLE `{table_name}` ADD {column}"
_ALTER_DEFAULT_TEMPLATE = "ALTER TABLE `{table_name}` ALTER COLUMN `{column}` {default}"
_CHANGE_COLUMN_TEMPLATE = (
"ALTER TABLE `{table_name}` CHANGE {old_column_name} {new_column_name} {new_column_type}"
)
_DROP_COLUMN_TEMPLATE = "ALTER TABLE `{table_name}` DROP COLUMN `{column_name}`"
_RENAME_COLUMN_TEMPLATE = (
"ALTER TABLE `{table_name}` RENAME COLUMN `{old_column_name}` TO `{new_column_name}`"
)
_ADD_INDEX_TEMPLATE = (
"ALTER TABLE `{table_name}` ADD {unique}INDEX `{index_name}` ({column_names})"
)
_DROP_INDEX_TEMPLATE = "ALTER TABLE `{table_name}` DROP INDEX `{index_name}`"
_ADD_FK_TEMPLATE = "ALTER TABLE `{table_name}` ADD CONSTRAINT `{fk_name}` FOREIGN KEY (`{db_column}`) REFERENCES `{table}` (`{field}`) ON DELETE {on_delete}"
_DROP_FK_TEMPLATE = "ALTER TABLE `{table_name}` DROP FOREIGN KEY `{fk_name}`"
_M2M_TABLE_TEMPLATE = (
"CREATE TABLE `{table_name}` (\n"
" `{backward_key}` {backward_type} NOT NULL REFERENCES `{backward_table}` (`{backward_field}`) ON DELETE CASCADE,\n"
" `{forward_key}` {forward_type} NOT NULL REFERENCES `{forward_table}` (`{forward_field}`) ON DELETE CASCADE\n"
"){extra}{comment}"
)
_MODIFY_COLUMN_TEMPLATE = "ALTER TABLE `{table_name}` MODIFY COLUMN {column}"
_RENAME_TABLE_TEMPLATE = "ALTER TABLE `{old_table_name}` RENAME TO `{new_table_name}`"
def _index_name(self, unique: bool, model: "Type[Model]", field_names: List[str]) -> str:
if unique:
if len(field_names) == 1:
# Example: `email = CharField(max_length=50, unique=True)`
# Generate schema: `"email" VARCHAR(10) NOT NULL UNIQUE`
# Unique index key is the same as field name: `email`
return field_names[0]
index_prefix = "uid"
else:
index_prefix = "idx"
return self.schema_generator._generate_index_name(index_prefix, model, field_names)
def add_index(self, model: "Type[Model]", field_names: List[str], unique=False) -> str:
return self._ADD_INDEX_TEMPLATE.format(
unique="UNIQUE " if unique else "",
index_name=self._index_name(unique, model, field_names),
table_name=model._meta.db_table,
column_names=", ".join(self.schema_generator.quote(f) for f in field_names),
)
def drop_index(self, model: "Type[Model]", field_names: List[str], unique=False) -> str:
return self._DROP_INDEX_TEMPLATE.format(
index_name=self._index_name(unique, model, field_names),
table_name=model._meta.db_table,
)