config に移した．

db/config.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+import os
+from typing import TypedDict
+
+from eloquent import DatabaseManager, Model  # type: ignore
+
+CONFIG: dict[str, DbConfig] = { 'mysql': { 'driver':    'mysql',
+                                           'host':      'localhost',
+                                           'database':  'nizika_nico',
+                                           'user':      os.environ['MYSQL_USER'],
+                                           'password':  os.environ['MYSQL_PASS'],
+                                           'prefix':    '' } }
+
+DB = DatabaseManager (CONFIG)
+Model.set_connection_resolver (DB)
+
+
+class DbConfig (TypedDict):
+    driver:     str
+    host:       str
+    database:   str
+    user:       str
+    password:   str
+    prefix:     str

update_db.py

@@ -20,24 +20,25 @@ import jaconv
 import requests
 from eloquent import DatabaseManager, Model
 
+from db.config import DB
 from db.models import Comment, Tag, User, Video, VideoHistory, VideoTag
 
 
 def main (
 ) -> None:
-    config: dict[str, DbConfig] = { 'mysql': { 'driver':    'mysql',
-                                               'host':      'localhost',
-                                               'database':  'nizika_nico',
-                                               'user':      os.environ['MYSQL_USER'],
-                                               'password':  os.environ['MYSQL_PASS'],
-                                               'prefix':    '' } }
-    db = DatabaseManager (config)
-    Model.set_connection_resolver (db)
-
     now = datetime.now ()
 
-    api_data = search_nico_by_tags (['伊地知ニジカ', 'ぼざろクリーチャーシリーズ', 'ぼざろクリーチャーシリーズ外伝'])
+    api_data = search_nico_by_tags (['伊地知ニジカ',
+                                     'ぼざろクリーチャーシリーズ',
+                                     'ぼざろクリーチャーシリーズ外伝'])
+
+    DB.begin_transaction ()
+    try:
         update_tables (api_data, now)
+        DB.commit ()
+    except Exception:
+        DB.rollback ()
+        raise
 
 
 def update_tables (
@@ -211,15 +212,6 @@ def search_nico_by_tags (
     return result_data
 
 
-class DbConfig (TypedDict):
-    driver:     str
-    host:       str
-    database:   str
-    user:       str
-    password:   str
-    prefix:     str
-
-
 class VideoSearchParam (TypedDict):
     q:          str
     targets:    str