Geojson viewer app

This is a small demo application using plotly's dash framework. Dash was chosen because it combines relatively simple and straight forward means for creating interactive react.js web apps and is still able to fulfill the requirements of this small application. Those requirements are:

Upload GeoJSON files, containing geo-referenced features and their properties.
Show uploaded features and their properties on a dynamic web map.
Modify existing properties for features shown on the map.
Save updated features with their properties to GeoJson file.

Installation

Pre-requisites

The application backend runs in a python environment, hence python should be available on your computer.

Using anaconda (recommended)

This application is best set up by is using a dedicated anaconda environment. Hence it is strongly recommended to have anaconda installed on the executing computer. All dependencies can be installed using the following conda command:

conda env create -q -n geoviewer python=3.10 -f environment.yml

Resolving dependencies can be quite slow. An alternative is using mamba instead of conda.

mamba env create -q -n geoviewer python=3.10 -f environment.yml

Using pip (virtualenv, pipenv etc)

If conda is not available you can directly install the dependencies via pip. Still, it is recommended to use some kind of isolated python environment for example provided by virtualenv or pipenv.

python -m pip install .

Usage

If you have used the recommended anaconda command above you'd have to activate the environment first:

conda activate geoviewer

To start the application use the following command:

geojson-viewer --help
usage: geojson-viewer [-h] [--debug] [--port PORT] [-V]

View and manipulate geojson files

options:
  -h, --help     show this help message and exit
  --debug
  --port PORT    The port the app should be running on. (default: 8050)
  -V, --version  show program's version number and exit

For example the command:

geojson-viewer --debug

will start the application in debug mode on port 8050. You can then open the app via http://localhost:8050/ on your browser.

Fallback

If the installation fails and you have access to docker on your machine you can use the fallback solution of creating a docker container and running the app inside the container. For example:

docker build -t geoviewer . && docker run -it --net=host geoviewer geojson-viewer --debug

Sample data

Sample geojson data is provided in the repository (montreal_elections.geojson) the same data can also be accessed via the following url:

https://nextcloud.dkrz.de/s/keAxAjE5SMFQZ7C/download/montreal_elections.geojson

antarcticrainforest / geojson-viewer