issue_comments

Hi @wragge,

This 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 :/

```python import socket

from signal import SIGINT from subprocess import Popen, PIPE

from IPython.display import display, HTML from notebook.notebookapp import list_running_servers

def get_free_tcp_port(): """ Get a free TCP port. """ tcp = socket.socket(socket.AF_INET, socket.SOCK_STREAM) tcp.bind(('', 0)) _, port = tcp.getsockname() tcp.close() return port

def datasette(database): """ Run datasette on an SQLite database. """ # Get current running servers servers = list_running_servers()

# Get the current base url
base_url = next(servers)['base_url']

# Get a free port
port = get_free_tcp_port()

# Create a base url for Datasette suing the proxy path
proxy_url = f'{base_url}proxy/absolute/{port}/'

# Display a link to Datasette
display(HTML(f'<p><a href="{proxy_url}">View Datasette</a> (Click on the stop button to close the Datasette server)</p>'))

# Launch Datasette
with Popen(
    [
        'python', '-m', 'datasette', '--',
        database,
        '--port', str(port),
        '--config', f'base_url:{proxy_url}'
    ],
    stdout=PIPE,
    stderr=PIPE,
    bufsize=1,
    universal_newlines=True
) as p:
    print(p.stdout.readline(), end='')
    while True:
        try:
            line = p.stderr.readline()
            if not line:
                break
            print(line, end='')
            exit_code = p.poll()
        except KeyboardInterrupt:
            p.send_signal(SIGINT)

```

Ideally, 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.

Hi,

I came across this issue while looking for a way to spawn Datasette as a SQLite files viewer in JupyterLab. I found https://github.com/simonw/jupyterserverproxy-datasette-demo which seems to be the most up to date proof of concept, but it seems to be failing to list the available db (at least in the Binder demo, https://hub.gke.mybinder.org/user/simonw-jupyters--datasette-demo-uw4dmlnn/datasette/, I only have :memory).

Does anyone tried to improve on this proof of concept to have a Datasette visualization for SQLite files?

Thanks!