Fix migrate to new database error

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## 0.3
 
+### 0.3.2
+
+- Fix migrate to new database error. (#62)
+
 ### 0.3.1
 
 - Fix first version error.

aerich/__init__.py

@@ -1 +1 @@
-__version__ = "0.3.1"
+__version__ = "0.3.2"

aerich/migrate.py

@@ -4,7 +4,7 @@ import re
 from datetime import datetime
 from importlib import import_module
 from io import StringIO
-from typing import Dict, List, Tuple, Type
+from typing import Dict, List, Optional, Tuple, Type
 
 import click
 from tortoise import (
@@ -15,6 +15,7 @@ from tortoise import (
     Model,
     Tortoise,
 )
+from tortoise.exceptions import OperationalError
 from tortoise.fields import Field
 
 from aerich.ddl import BaseDDL
@@ -53,8 +54,11 @@ class Migrate:
         )
 
     @classmethod
-    async def get_last_version(cls) -> Aerich:
+    async def get_last_version(cls) -> Optional[Aerich]:
+        try:
             return await Aerich.filter(app=cls.app).first()
+        except OperationalError:
+            pass
 
     @classmethod
     def remove_old_model_file(cls, app: str, location: str):
@@ -67,16 +71,15 @@ class Migrate:
     async def init_with_old_models(cls, config: dict, app: str, location: str):
         await Tortoise.init(config=config)
         last_version = await cls.get_last_version()
+        cls.app = app
+        cls.migrate_location = os.path.join(location, app)
         if last_version:
             content = last_version.content
             with open(cls.get_old_model_file(app, location), "w") as f:
                 f.write(content)
 
             migrate_config = cls._get_migrate_config(config, app, location)
-        cls.app = app
             cls.migrate_config = migrate_config
-        cls.migrate_location = os.path.join(location, app)
-
             await Tortoise.init(config=migrate_config)
 
         connection = get_app_connection(config, app)

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "aerich"
-version = "0.3.1"
+version = "0.3.2"
 description = "A database migrations tool for Tortoise ORM."
 authors = ["long2ice <long2ice@gmail.com>"]
 license = "Apache-2.0"