aerich/aerich/ddl/postgres/__init__.py
2020-07-20 10:20:08 +08:00

51 lines
2.1 KiB
Python

from typing import Type
from tortoise import Model
from tortoise.backends.asyncpg.schema_generator import AsyncpgSchemaGenerator
from tortoise.fields import Field
from aerich.ddl import BaseDDL
class PostgresDDL(BaseDDL):
schema_generator_cls = AsyncpgSchemaGenerator
DIALECT = AsyncpgSchemaGenerator.DIALECT
_ALTER_DEFAULT_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" {default}'
_ALTER_NULL_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" {set_drop} NOT NULL'
_MODIFY_COLUMN_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" TYPE {datatype}'
_SET_COMMENT_TEMPLATE = 'COMMENT ON COLUMN "{table_name}"."{column}" IS {comment}'
_DROP_FK_TEMPLATE = 'ALTER TABLE "{table_name}" DROP CONSTRAINT "{fk_name}"'
def alter_column_default(self, model: "Type[Model]", field_object: Field):
db_table = model._meta.db_table
default = self._get_default(model, field_object)
return self._ALTER_DEFAULT_TEMPLATE.format(
table_name=db_table,
column=field_object.model_field_name,
default="SET" + default if default else "DROP DEFAULT",
)
def alter_column_null(self, model: "Type[Model]", field_object: Field):
db_table = model._meta.db_table
return self._ALTER_NULL_TEMPLATE.format(
table_name=db_table,
column=field_object.model_field_name,
set_drop="DROP" if field_object.null else "SET",
)
def modify_column(self, model: "Type[Model]", field_object: Field):
db_table = model._meta.db_table
return self._MODIFY_COLUMN_TEMPLATE.format(
table_name=db_table,
column=field_object.model_field_name,
datatype=field_object.get_for_dialect(self.DIALECT, "SQL_TYPE"),
)
def set_comment(self, model: "Type[Model]", field_object: Field):
db_table = model._meta.db_table
return self._SET_COMMENT_TEMPLATE.format(
table_name=db_table,
column=field_object.model_field_name,
comment="'{}'".format(field_object.description) if field_object.description else "NULL",
)