How can I work with ngrok in google colab?

Question

I am using this workaround with ngrok in Google Colab. My goal is to tunnel some dataframe to a public url so that I can share the output with my colleagues.

How I install ngrok:

%%sh
# get ngrok
curl -O https://bin.equinox.io/c/4VmDzA7iaHb/ngrok-stable-linux-amd64.zip
unzip ngrok-stable-linux-amd64.zip

My py file:

%%writefile dash_app.py
import pandas as pd 
import dash
from dash import dcc
from dash import html
from dash import dash_table

external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']

app = dash.Dash(__name__)#, external_stylesheets=external_stylesheets)
# Load Data

df = pd.read_excel('CM_Ratiosppt.xlsx')

#[df[i]=df[i].round(2) for i in df.columns]
# Build App


app.layout = dash_table.DataTable(
    id='table',
    columns=[{"name": i, "id": i} for i in df.columns],
    data=df.to_dict('records'),
)

if __name__ == '__main__':
    app.run_server(debug=False)

# launch ngrok
get_ipython().system_raw('./ngrok http 8050 &')
!python dash_app.py

getting the ngrok url:

%%sh
# get url with ngrok
curl -s http://localhost:4040/api/tunnels | python3 -c "import sys, json; print(json.load(sys.stdin)['tunnels'][0]['public_url'])"

However, I get this error:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3.7/json/__init__.py", line 296, in load
    parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
  File "/usr/lib/python3.7/json/__init__.py", line 348, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.7/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.7/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Answer 1

Mount your google drive & symlink it to /drive

https://colab.research.google.com/github/shawwn/colab-tricks/blob/master/ngrok-tricks.ipynb