Binder env not working for local COG

[giswqs]

The binder env works well when rending a remote COG. However, it does not seem to work for a local COG (a file in the repo). The tile layer won't show up.

!wget https://github.com/giswqs/data/raw/main/raster/srtm90.tif

from localtileserver import get_leaflet_tile_layer, TileClient
from ipyleaflet import Map

# First, create a tile server from local raster file
tile_client = TileClient('srtm90.tif')

# Create ipyleaflet tile layer from that server
t = get_leaflet_tile_layer(tile_client)

# Create ipyleaflet map, add tile layer, and display
m = Map(center=tile_client.center())
m.add_layer(t)
m

[banesullivan]

This is known/expected because of banesullivan/localtileserver#29

I do not know of a way to expose a server from the binder env that is accessible in the user's browser

[banesullivan]

TileClient will not work in this sort of environment, only RemoteTileClient which is connecting to a production server I have running (not very performant)

[giswqs]

I was exploring the following repo this morning. It can run a streamlit web app on Binder. Not sure if it would be useful in your case.

https://github.com/chekos/testing-streamlit-mybinder
https://mybinder.org/v2/gh/chekos/testing-streamlit-mybinder/master?urlpath=proxy/8501/

[banesullivan]

Ah, that demo is just what I needed to see! I will see if I can do something similar with localtileserver

[banesullivan]

This is now working using jupyter-server-proxy. Please note the line at the top of example.ipynb that enables this to work:

# Set host forwarding for MyBinder
import os
# Make sure `notebooks.gesis.org/binder/jupyter/user/` matches your URL address
os.environ['LOCALTILESERVER_CLIENT_HOST'] = f"notebooks.gesis.org/binder/jupyter/user/{os.environ['JUPYTERHUB_USER']}"

That HOST URL might change on different mybinder or jupyterhub deployments

[giswqs]

I just tested it on binder with the latest localtilesever. It does not seem to work.

https://gishub.org/leafmap-binder

[banesullivan]

Make sure to use the --pre flag for pip as I only released a dev version for this 0.4.1.dev0

I want to double check things before doing an actual release

[banesullivan]

Also, you'll need to install https://jupyter-server-proxy.readthedocs.io/en/latest/ and make sure its extensions are enabled

[banesullivan]

Ignore the --pre flag comment. Just noticed you're installing from git

[giswqs]

This is what I tried with my leafmap binder. Still not working. Not sure what I did wrong.

https://gishub.org/leafmap-binder

!pip install git+https://github.com/banesullivan/localtileserver.git
!pip install jupyter-server-proxy
!jupyter serverextension enable --sys-prefix jupyter_server_proxy

[giswqs]

Your gesis binder works fine. So the issue is probably related to how the binder env is set up. Your uses docker, mine uses environment.yml

[banesullivan]

I think you'll have to relaunch Jupyter after enabling the server extension

Also make sure that code block at the top setting LOCALTILESERVER_CLIENT_HOST is uncommented and that variable is set

[giswqs]

Yes, i did restart the kernel several times. Also uncommented that line. Still not working. Will look into it tomorrow. Thanks

[banesullivan]

After uncommenting that line, make sure that value matches the URL in your browser

[giswqs]

Is this correct?

if os.environ.get('JUPYTERHUB_USER'):  
    os.environ['LOCALTILESERVER_CLIENT_HOST'] = f"hub.gke2.mybinder.org/user/{os.environ['JUPYTERHUB_USER']}"
else:
    os.environ['LOCALTILESERVER_CLIENT_PORT'] = '8888'
    os.environ['LOCALTILESERVER_CLIENT_HOST'] = "127.0.0.0"
    os.environ['LOCALTILESERVER_CLIENT_PREFIX'] = 'proxy/{port}'

[banesullivan]

You need to set os.environ['LOCALTILESERVER_CLIENT_PREFIX'] = 'proxy/{port}' in both cases

note that MyBinder's host can change anytime you launch, so hub.gke2.mybinder.org/user/ will not always be correct

[giswqs]

Is there a way to retrieve the host URL programmatically?

[banesullivan]

There's always a way! ....but I couldn't figure it out... 😞

The host is not listed in os.environ but it could be somewhere...

I tried:

from notebook import notebookapp
servers = list(notebookapp.list_running_servers())
print(servers)

... 'hostname': '0.0.0.0' ...

But there's another webserver on top that manages the traffic.

I bet we could make a super hacky way of getting this through a custom ipython widget where the widget accesses window.location.href in the browser and then sends that data back to Python. However, this would be quite hacky and would require the user to display the widget.

This question might be something https://discourse.jupyter.org/c/binder/12 could help address

[banesullivan]

ACTUALLY! I just found a much, much simpler way to do this.

[banesullivan]

I will follow up in a PR in localtileserver

[banesullivan]

See banesullivan/localtileserver#67

After that, the following should be sufficient:

# Set host forwarding for MyBinder
import os
os.environ['LOCALTILESERVER_CLIENT_PREFIX'] = f"{os.environ['JUPYTERHUB_SERVICE_PREFIX'].lstrip('/')}/proxy/{{port}}"

[giswqs]

Fantastic! I can confirm that v0.4.3 works like a charm with Binder. How to make it work with other remote environments not using JupyterHub (e.g., streamlit)?

# Set host forwarding for MyBinder
import os
os.environ['LOCALTILESERVER_CLIENT_PREFIX'] = f"{os.environ['JUPYTERHUB_SERVICE_PREFIX'].lstrip('/')}/proxy/{{port}}"

[banesullivan]

How to make it work with other remote environments not using JupyterHub (e.g., streamlit)?

Let's open a new issue in localtileserver to address this

It should be a simple configuration with the settings I added for JupyterHub

[wzp8023391]

how to display raster image in remote environments, especially for streamlit?

[giswqs]

@wzp8023391 Unfortunately, localtileserver does not support streamlit. It is a streamlit problem rather than localtileserver.