Process died due to a locked database

Hi,

I'm using Python 2.7.12 with Scrapyd 1.2.1 and Twisted 19.10.0 running inside a Docker container. I've recently encounted this message in Scrapyd log:

2020-03-25T00:00:26+0000 [-] Process started:  project='foo' spider='bar' job='a136c0c86e2b11eaa7e00242ac110004
' pid=11430 log='/var/lib/scrapyd/logs/foo/bar/a136c0c86e2b11eaa7e00242ac110004.log' items=None
...
2020-03-25T00:00:36+0000 [Launcher,11430/stderr] Traceback (most recent call last):
          File "/usr/lib/python2.7/runpy.py", line 174, in _run_module_as_main
            "__main__", fname, loader, pkg_name)
          File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
            exec code in run_globals
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/runner.py", line 40, in <module>
            main()
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/runner.py", line 35, in main
            with project_environment(project):
          File "/usr/lib/python2.7/contextlib.py", line 17, in __enter__
            return self.gen.next()
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/runner.py", line 13, in project_environment
            app = get_application()
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/__init__.py", line 15, in get_application
            return appfunc(config)
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/app.py", line 39, in application
            webservice = TCPServer(http_port, server.Site(webcls(config, app)), interface=bind_address)
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/website.py", line 35, in __init__
            self.update_projects()
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/website.py", line 38, in update_projects
            self.poller.update_projects()
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/poller.py", line 31, in update_projects
            self.queues = get_spider_queues(self.config)
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/utils.py", line 62, in get_spider_queues
            d[project] = SqliteSpiderQueue(dbpath)
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/spiderqueue.py", line 11, in __init__
            self.q = JsonSqlitePriorityQueue(database, table)
          File "/usr/local/lib/python2.7/dist-packages/scrapyd/sqlite.py", line 117, in __init__
            self.conn.execute(q)
        sqlite3.OperationalError: database is locked
...
2020-03-25T00:00:37+0000 [-] Process died: exitstatus=1  project='foo' spider='bar' job='a136c0c86e2b11eaa7e00242ac110004' pid=11430 log='/var/lib/scrapyd/logs/foo/bar/a136c0c86e2b11eaa7e00242ac110004.log' items=None

When I look at Jobs page on Scrapyd web, I can see an entry there:

foo | bar | a136c0c86e2b11eaa7e00242ac110004 |   | 2020-03-25 00:00:26 | 0:00:11 | 2020-03-25 00:00:37 | Log

However, the log file is unavailable, I'm getting 404 No Such Resource error.

scrapy / scrapyd

Process died due to a locked database #371