fix: keep one douyu cookie per account

web/backend/migrations/versions/20260808_0019_dedupe_douyu_success_cookies.py

@@ -0,0 +1,66 @@
+"""清理斗鱼账号重复成功 Cookie 记录
+
+Revision ID: 20260808_0019
+Revises: 20260807_0018
+Create Date: 2026-08-08
+"""
+
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+revision: str = "20260808_0019"
+down_revision: Union[str, None] = "20260807_0018"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    bind = op.get_bind()
+    inspector = sa.inspect(bind)
+    if not inspector.has_table("login_tasks"):
+        return
+
+    task_table = sa.table(
+        "login_tasks",
+        sa.column("id", sa.Integer),
+        sa.column("account_id", sa.Integer),
+        sa.column("status", sa.String),
+        sa.column("finished_at", sa.DateTime),
+    )
+    rows = bind.execute(
+        sa.select(
+            task_table.c.id,
+            task_table.c.account_id,
+            task_table.c.finished_at,
+        )
+        .where(task_table.c.status == "success")
+        .order_by(
+            task_table.c.account_id.asc(),
+            task_table.c.finished_at.desc(),
+            task_table.c.id.desc(),
+        )
+    ).all()
+
+    delete_ids: list[int] = []
+    seen_accounts: set[int] = set()
+    for row in rows:
+        if row.account_id in seen_accounts:
+            delete_ids.append(row.id)
+            continue
+        seen_accounts.add(row.account_id)
+
+    if not delete_ids:
+        return
+
+    for index in range(0, len(delete_ids), 500):
+        chunk = delete_ids[index:index + 500]
+        bind.execute(
+            task_table.delete().where(task_table.c.id.in_(chunk))
+        )
+
+
+def downgrade() -> None:
+    pass