{"html_url": "https://github.com/simonw/datasette/issues/394#issuecomment-642522285", "issue_url": "https://api.github.com/repos/simonw/datasette/issues/394", "id": 642522285, "node_id": "MDEyOklzc3VlQ29tbWVudDY0MjUyMjI4NQ==", "user": {"value": 58298410, "label": "LVerneyPEReN"}, "created_at": "2020-06-11T09:15:19Z", "updated_at": "2020-06-11T09:15:19Z", "author_association": "NONE", "body": "Hi @wragge,\r\n\r\nThis looks great, thanks for the share! I refactored it into a self-contained function, binding on a random available TCP port (multi-user context). I am using subprocess API directly since the `%run` magic was leaving defunct process behind :/\r\n\r\n![image](https://user-images.githubusercontent.com/58298410/84367566-b5d0d500-abd4-11ea-96e2-f5c05a28e506.png)\r\n\r\n```python\r\nimport socket\r\n\r\nfrom signal import SIGINT\r\nfrom subprocess import Popen, PIPE\r\n\r\nfrom IPython.display import display, HTML\r\nfrom notebook.notebookapp import list_running_servers\r\n\r\n\r\ndef get_free_tcp_port():\r\n    \"\"\"\r\n    Get a free TCP port.\r\n    \"\"\"\r\n    tcp = socket.socket(socket.AF_INET, socket.SOCK_STREAM)\r\n    tcp.bind(('', 0))\r\n    _, port = tcp.getsockname()\r\n    tcp.close()\r\n    return port\r\n\r\n\r\ndef datasette(database):\r\n    \"\"\"\r\n    Run datasette on an SQLite database.\r\n    \"\"\"\r\n    # Get current running servers\r\n    servers = list_running_servers()\r\n\r\n    # Get the current base url\r\n    base_url = next(servers)['base_url']\r\n\r\n    # Get a free port\r\n    port = get_free_tcp_port()\r\n\r\n    # Create a base url for Datasette suing the proxy path\r\n    proxy_url = f'{base_url}proxy/absolute/{port}/'\r\n\r\n    # Display a link to Datasette\r\n    display(HTML(f'<p><a href=\"{proxy_url}\">View Datasette</a> (Click on the stop button to close the Datasette server)</p>'))\r\n\r\n    # Launch Datasette\r\n    with Popen(\r\n        [\r\n            'python', '-m', 'datasette', '--',\r\n            database,\r\n            '--port', str(port),\r\n            '--config', f'base_url:{proxy_url}'\r\n        ],\r\n        stdout=PIPE,\r\n        stderr=PIPE,\r\n        bufsize=1,\r\n        universal_newlines=True\r\n    ) as p:\r\n        print(p.stdout.readline(), end='')\r\n        while True:\r\n            try:\r\n                line = p.stderr.readline()\r\n                if not line:\r\n                    break\r\n                print(line, end='')\r\n                exit_code = p.poll()\r\n            except KeyboardInterrupt:\r\n                p.send_signal(SIGINT)\r\n```\r\n\r\nIdeally, I'd like some extra magic to notify users when they are leaving the closing the notebook tab and make them terminate the running datasette processes. I'll be looking for it.", "reactions": "{\"total_count\": 1, \"+1\": 0, \"-1\": 0, \"laugh\": 0, \"hooray\": 0, \"confused\": 0, \"heart\": 1, \"rocket\": 0, \"eyes\": 0}", "issue": {"value": 396212021, "label": "base_url configuration setting"}, "performed_via_github_app": null}