{"comment":{"url":"https://api.github.com/repos/spotify/luigi/comments/9686894","html_url":"https://github.com/spotify/luigi/commit/7707525a4f929226acfb0cd10e5667ddee8ec9cd#commitcomment-9686894","id":9686894,"user":{"login":"jbalogh","id":57258,"avatar_url":"https://avatars.githubusercontent.com/u/57258?v=3","gravatar_id":"","url":"https://api.github.com/users/jbalogh","html_url":"https://github.com/jbalogh","followers_url":"https://api.github.com/users/jbalogh/followers","following_url":"https://api.github.com/users/jbalogh/following{/other_user}","gists_url":"https://api.github.com/users/jbalogh/gists{/gist_id}","starred_url":"https://api.github.com/users/jbalogh/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/jbalogh/subscriptions","organizations_url":"https://api.github.com/users/jbalogh/orgs","repos_url":"https://api.github.com/users/jbalogh/repos","events_url":"https://api.github.com/users/jbalogh/events{/privacy}","received_events_url":"https://api.github.com/users/jbalogh/received_events","type":"User","site_admin":false},"position":93,"line":428,"path":"luigi/scheduler.py","commit_id":"7707525a4f929226acfb0cd10e5667ddee8ec9cd","created_at":"2015-02-11T00:25:47Z","updated_at":"2015-02-11T00:25:47Z","body":"This is causing an error at import time for me. Our setup has the scheduler running on boxA and tasks are scheduled from boxB. They share a `luigi/client.cfg`, so this change plus the existing `CentralPlannerScheduler()` created as a default parameter for `class Worker` leads to sqlalchemy trying to create a database on boxB.\r\n\r\n```python\r\nTraceback (most recent call last):\r\n  File \"run.py\", line 4, in <module>\r\n    import luigi\r\n  File \"vendor/src/luigi/luigi/__init__.py\", line 26, in <module>\r\n    import interface\r\n  File \"vendor/src/luigi/luigi/interface.py\", line 32, in <module>\r\n    import worker\r\n  File \"vendor/src/luigi/luigi/worker.py\", line 257, in <module>\r\n    class Worker(object):\r\n  File \"vendor/src/luigi/luigi/worker.py\", line 267, in Worker\r\n    def __init__(self, scheduler=CentralPlannerScheduler(), worker_id=None,\r\n  File \"vendor/src/luigi/luigi/scheduler.py\", line 430, in __init__\r\n    self._task_history = db_task_history.DbTaskHistory()\r\n  File \"vendor/src/luigi/luigi/db_task_history.py\", line 59, in __init__\r\n    Base.metadata.create_all(self.engine)\r\n  ...\r\n  sqlalchemy.exc.OperationalError: (OperationalError) unable to open database file None None\r\n```"}}