Fail to run JupyterDash demo

I has been a long time user of plotly and dash, and was excited to try out the new JupyterDash package, but was unable to get it to work.
I am using a mac, with the following setup:
plotly = 4.9.0
jupyter_dash = 0.3.0
dash_core_components = 1.10.1
dash_html_components = 1.0.1
nodejs = v14.7.0
jupyterlab = 2.2.0
and have the jupyter-dash extension build.
I have tried to update my nodejs version and reinstall jupyter_dash without success. I don’t know what else I could try, so please help or let me know what other information I need to provide. Thanks in advance!

The code I am using are

import plotly.express as px
from jupyter_dash import JupyterDash
import dash_core_components as dcc
import dash_html_components as html
from dash.dependencies import Input, Output
# Load Data
df = px.data.tips()
# Build App
app = JupyterDash(__name__)
app.layout = html.Div([
    html.H1("JupyterDash Demo"),
    dcc.Graph(id='graph'),
    html.Label([
        "colorscale",
        dcc.Dropdown(
            id='colorscale-dropdown', clearable=False,
            value='plasma', options=[
                {'label': c, 'value': c}
                for c in px.colors.named_colorscales()
            ])
    ]),
])
# Define callback to update graph
@app.callback(
    Output('graph', 'figure'),
    [Input("colorscale-dropdown", "value")]
)
def update_figure(colorscale):
    return px.scatter(
        df, x="total_bill", y="tip", color="size",
        color_continuous_scale=colorscale,
        render_mode="webgl", title="Tips"
    )
# Run app and display result inline in the notebook
app.run_server(mode='inline')

and I got the following error message:

---------------------------------------------------------------------------
gaierror                                  Traceback (most recent call last)
~/opt/anaconda3/lib/python3.7/site-packages/urllib3/connection.py in _new_conn(self)
    156             conn = connection.create_connection(
--> 157                 (self._dns_host, self.port), self.timeout, **extra_kw
    158             )

~/opt/anaconda3/lib/python3.7/site-packages/urllib3/util/connection.py in create_connection(address, timeout, source_address, socket_options)
     60 
---> 61     for res in socket.getaddrinfo(host, port, family, socket.SOCK_STREAM):
     62         af, socktype, proto, canonname, sa = res

~/opt/anaconda3/lib/python3.7/socket.py in getaddrinfo(host, port, family, type, proto, flags)
    751     addrlist = []
--> 752     for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
    753         af, socktype, proto, canonname, sa = res

gaierror: [Errno 8] nodename nor servname provided, or not known

During handling of the above exception, another exception occurred:

NewConnectionError                        Traceback (most recent call last)
~/opt/anaconda3/lib/python3.7/site-packages/urllib3/connectionpool.py in urlopen(self, method, url, body, headers, retries, redirect, assert_same_host, timeout, pool_timeout, release_conn, chunked, body_pos, **response_kw)
    671                 headers=headers,
--> 672                 chunked=chunked,
    673             )

~/opt/anaconda3/lib/python3.7/site-packages/urllib3/connectionpool.py in _make_request(self, conn, method, url, timeout, chunked, **httplib_request_kw)
    386         else:
--> 387             conn.request(method, url, **httplib_request_kw)
    388 

~/opt/anaconda3/lib/python3.7/http/client.py in request(self, method, url, body, headers, encode_chunked)
   1251         """Send a complete request to the server."""
-> 1252         self._send_request(method, url, body, headers, encode_chunked)
   1253 

~/opt/anaconda3/lib/python3.7/http/client.py in _send_request(self, method, url, body, headers, encode_chunked)
   1297             body = _encode(body, 'body')
-> 1298         self.endheaders(body, encode_chunked=encode_chunked)
   1299 

~/opt/anaconda3/lib/python3.7/http/client.py in endheaders(self, message_body, encode_chunked)
   1246             raise CannotSendHeader()
-> 1247         self._send_output(message_body, encode_chunked=encode_chunked)
   1248 

~/opt/anaconda3/lib/python3.7/http/client.py in _send_output(self, message_body, encode_chunked)
   1025         del self._buffer[:]
-> 1026         self.send(msg)
   1027 

~/opt/anaconda3/lib/python3.7/http/client.py in send(self, data)
    965             if self.auto_open:
--> 966                 self.connect()
    967             else:

~/opt/anaconda3/lib/python3.7/site-packages/urllib3/connection.py in connect(self)
    183     def connect(self):
--> 184         conn = self._new_conn()
    185         self._prepare_conn(conn)

~/opt/anaconda3/lib/python3.7/site-packages/urllib3/connection.py in _new_conn(self)
    168             raise NewConnectionError(
--> 169                 self, "Failed to establish a new connection: %s" % e
    170             )

NewConnectionError: <urllib3.connection.HTTPConnection object at 0x7fa3adb64190>: Failed to establish a new connection: [Errno 8] nodename nor servname provided, or not known

During handling of the above exception, another exception occurred:

MaxRetryError                             Traceback (most recent call last)
~/opt/anaconda3/lib/python3.7/site-packages/requests/adapters.py in send(self, request, stream, timeout, verify, cert, proxies)
    448                     retries=self.max_retries,
--> 449                     timeout=timeout
    450                 )

~/opt/anaconda3/lib/python3.7/site-packages/urllib3/connectionpool.py in urlopen(self, method, url, body, headers, retries, redirect, assert_same_host, timeout, pool_timeout, release_conn, chunked, body_pos, **response_kw)
    719             retries = retries.increment(
--> 720                 method, url, error=e, _pool=self, _stacktrace=sys.exc_info()[2]
    721             )

~/opt/anaconda3/lib/python3.7/site-packages/urllib3/util/retry.py in increment(self, method, url, response, error, _pool, _stacktrace)
    435         if new_retry.is_exhausted():
--> 436             raise MaxRetryError(_pool, url, error or ResponseError(cause))
    437 

MaxRetryError: HTTPConnectionPool(host='x86_64-apple-darwin13.4.0', port=8050): Max retries exceeded with url: /_alive_98c9c9e9-2b68-4827-9e79-414975a06037 (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7fa3adb64190>: Failed to establish a new connection: [Errno 8] nodename nor servname provided, or not known'))

During handling of the above exception, another exception occurred:

ConnectionError                           Traceback (most recent call last)
<ipython-input-3-04de55125734> in <module>
     33     )
     34 # Run app and display result inline in the notebook
---> 35 app.run_server(mode='inline')

~/opt/anaconda3/lib/python3.7/site-packages/jupyter_dash/jupyter_app.py in run_server(self, mode, width, height, inline_exceptions, **kwargs)
    317                 )
    318 
--> 319         wait_for_app()
    320 
    321         if JupyterDash._in_colab:

~/opt/anaconda3/lib/python3.7/site-packages/retrying.py in wrapped_f(*args, **kw)
     47             @six.wraps(f)
     48             def wrapped_f(*args, **kw):
---> 49                 return Retrying(*dargs, **dkw).call(f, *args, **kw)
     50 
     51             return wrapped_f

~/opt/anaconda3/lib/python3.7/site-packages/retrying.py in call(self, fn, *args, **kwargs)
    210                 if not self._wrap_exception and attempt.has_exception:
    211                     # get() on an attempt with an exception should cause it to be raised, but raise just in case
--> 212                     raise attempt.get()
    213                 else:
    214                     raise RetryError(attempt)

~/opt/anaconda3/lib/python3.7/site-packages/retrying.py in get(self, wrap_exception)
    245                 raise RetryError(self)
    246             else:
--> 247                 six.reraise(self.value[0], self.value[1], self.value[2])
    248         else:
    249             return self.value

~/opt/anaconda3/lib/python3.7/site-packages/six.py in reraise(tp, value, tb)
    701             if value.__traceback__ is not tb:
    702                 raise value.with_traceback(tb)
--> 703             raise value
    704         finally:
    705             value = None

~/opt/anaconda3/lib/python3.7/site-packages/retrying.py in call(self, fn, *args, **kwargs)
    198         while True:
    199             try:
--> 200                 attempt = Attempt(fn(*args, **kwargs), attempt_number, False)
    201             except:
    202                 tb = sys.exc_info()

~/opt/anaconda3/lib/python3.7/site-packages/jupyter_dash/jupyter_app.py in wait_for_app()
    305         )
    306         def wait_for_app():
--> 307             res = requests.get(alive_url).content.decode()
    308             if res != "Alive":
    309                 url = "http://{host}:{port}".format(

~/opt/anaconda3/lib/python3.7/site-packages/requests/api.py in get(url, params, **kwargs)
     73 
     74     kwargs.setdefault('allow_redirects', True)
---> 75     return request('get', url, params=params, **kwargs)
     76 
     77 

~/opt/anaconda3/lib/python3.7/site-packages/requests/api.py in request(method, url, **kwargs)
     58     # cases, and look like a memory leak in others.
     59     with sessions.Session() as session:
---> 60         return session.request(method=method, url=url, **kwargs)
     61 
     62 

~/opt/anaconda3/lib/python3.7/site-packages/requests/sessions.py in request(self, method, url, params, data, headers, cookies, files, auth, timeout, allow_redirects, proxies, hooks, stream, verify, cert, json)
    531         }
    532         send_kwargs.update(settings)
--> 533         resp = self.send(prep, **send_kwargs)
    534 
    535         return resp

~/opt/anaconda3/lib/python3.7/site-packages/requests/sessions.py in send(self, request, **kwargs)
    644 
    645         # Send the request
--> 646         r = adapter.send(request, **kwargs)
    647 
    648         # Total elapsed time of the request (approximately)

~/opt/anaconda3/lib/python3.7/site-packages/requests/adapters.py in send(self, request, stream, timeout, verify, cert, proxies)
    514                 raise SSLError(e, request=request)
    515 
--> 516             raise ConnectionError(e, request=request)
    517 
    518         except ClosedPoolError as e:

ConnectionError: HTTPConnectionPool(host='x86_64-apple-darwin13.4.0', port=8050): Max retries exceeded with url: /_alive_98c9c9e9-2b68-4827-9e79-414975a06037 (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7fa3adb64190>: Failed to establish a new connection: [Errno 8] nodename nor servname provided, or not known'))
Exception in thread Thread-5:
Traceback (most recent call last):
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/threading.py", line 926, in _bootstrap_inner
    self.run()
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/retrying.py", line 49, in wrapped_f
    return Retrying(*dargs, **dkw).call(f, *args, **kw)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/retrying.py", line 212, in call
    raise attempt.get()
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/retrying.py", line 247, in get
    six.reraise(self.value[0], self.value[1], self.value[2])
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/six.py", line 703, in reraise
    raise value
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/retrying.py", line 200, in call
    attempt = Attempt(fn(*args, **kwargs), attempt_number, False)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/jupyter_dash/jupyter_app.py", line 289, in run
    super_run_server(**kwargs)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/dash/dash.py", line 1615, in run_server
    self.server.run(host=host, port=port, debug=debug, **flask_run_options)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/flask/app.py", line 990, in run
    run_simple(host, port, self, **options)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/werkzeug/serving.py", line 1052, in run_simple
    inner()
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/werkzeug/serving.py", line 1005, in inner
    fd=fd,
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/werkzeug/serving.py", line 848, in make_server
    host, port, app, request_handler, passthrough_errors, ssl_context, fd=fd
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/site-packages/werkzeug/serving.py", line 740, in __init__
    HTTPServer.__init__(self, server_address, handler)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/socketserver.py", line 452, in __init__
    self.server_bind()
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/http/server.py", line 137, in server_bind
    socketserver.TCPServer.server_bind(self)
  File "/Users/tenggao/opt/anaconda3/lib/python3.7/socketserver.py", line 466, in server_bind
    self.socket.bind(self.server_address)
socket.gaierror: [Errno 8] nodename nor servname provided, or not known

Hey,
Try this:

app.run_server(mode='inline', host = '127.0.0.1')

If that doesn’t work, you can read more about your problem here.

1 Like

@adamschroeder Thank you very much! It solves my problems.