deerflow-code/offline-backend-20260512/backend/packages/harness/deerflow/persistence/migrations/env.py
2026-09-07 18:24:55 +08:00

85 lines
2.7 KiB
Python

"""Alembic environment for DeerFlow application tables.
ONLY manages DeerFlow's tables (runs, threads_meta, cron_jobs, users).
LangGraph's checkpointer tables are managed by LangGraph itself -- they
have their own schema lifecycle and must not be touched by Alembic.
"""
from __future__ import annotations
import asyncio
import logging
import os
from logging.config import fileConfig
from alembic import context
from sqlalchemy import text
from sqlalchemy.ext.asyncio import create_async_engine
from deerflow.persistence.base import Base
# Import all models so metadata is populated.
try:
import deerflow.persistence.models as models # register ORM models with Base.metadata
_ = models
except ImportError:
# Models not available — migration will work with existing metadata only.
logging.getLogger(__name__).warning("Could not import deerflow.persistence.models; Alembic may not detect all tables")
config = context.config
if config.config_file_name is not None:
fileConfig(config.config_file_name)
target_metadata = Base.metadata
def run_migrations_offline() -> None:
url = config.get_main_option("sqlalchemy.url")
context.configure(
url=url,
target_metadata=target_metadata,
literal_binds=True,
render_as_batch=True,
)
with context.begin_transaction():
context.run_migrations()
def do_run_migrations(connection):
render_as_batch = connection.dialect.name == "sqlite"
# On MySQL, shrink the session lock waits so a blocked DDL fails fast
# instead of hanging on the server default (lock_wait_timeout = 31536000s
# = 1 year; innodb_lock_wait_timeout = 50s). Without this, an idle
# transaction on another connection can freeze startup indefinitely.
# Tunable via DEER_FLOW_ALEMBIC_LOCK_WAIT (seconds, default 15).
if connection.dialect.name == "mysql":
try:
lock_wait = int(os.getenv("DEER_FLOW_ALEMBIC_LOCK_WAIT", "15"))
except ValueError:
lock_wait = 15
connection.execute(text(f"SET SESSION lock_wait_timeout = {lock_wait}"))
connection.execute(text(f"SET SESSION innodb_lock_wait_timeout = {lock_wait}"))
context.configure(
connection=connection,
target_metadata=target_metadata,
render_as_batch=render_as_batch, # Required for SQLite ALTER TABLE support
)
with context.begin_transaction():
context.run_migrations()
async def run_migrations_online() -> None:
connectable = create_async_engine(config.get_main_option("sqlalchemy.url"))
async with connectable.connect() as connection:
await connection.run_sync(do_run_migrations)
await connectable.dispose()
if context.is_offline_mode():
run_migrations_offline()
else:
asyncio.run(run_migrations_online())