simplified environment, updated readme

Author: scottyhq

README.md

@@ -1,32 +1,36 @@
 # repo2docker-githubci
-a template for building jupyterhub-compatible docker images with repo2docker and github actions
+a template for building [JupyterHub](https://jupyter.org/hub) environments with [Repo2Docker](https://repo2docker.readthedocs.io/en/latest/) and [GitHub Actions CI](https://help.github.com/en/actions/automating-your-workflow-with-github-actions) 
 
 ![Action Status](https://github.com/scottyhq/repo2docker-githubci/workflows/Repo2Docker/badge.svg)
+![Docker Pulls](https://img.shields.io/docker/pulls/scottyhq/repo2docker-githubci)
+[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/scottyhq/repo2docker-githubci/master?urlpath=lab)
 
-### how to use
+### How to use
 
-1) click the "Use this template" button to create a repo copy
+1) click the "Use this template" button to create your own repo
 
-1) create dockerhub account that matches your github username
+1) create DockerHub account that matches your GitHub username
 (could make this configurable)
 For example: https://hub.docker.com/u/scottyhq
 
 1) add DOCKER_USERNAME and DOCKER_PASSWORD to repo encrypyted secrets
 https://help.github.com/en/actions/automating-your-workflow-with-github-actions/creating-and-using-encrypted-secrets
 
-1) build with GitHub Action
+1) modify readme links and any files in the `binder/` folder
+
+1) build with GitHub Actions by pushing to GitHub
 * commits to master branch trigger re-building image tagged by github short sha and 'latest'
 ```
 git commit -a -m "modified binder/environment to my liking"
 git push
 ```
 * pushing a tag results in a docker image with the same tag:
 ```
-git tag -am "test v2.3.2" v2.3.2
+git tag -am "tagging 2.3.2" 2.3.2
 git push --tags
 ```
 
-### grab your image to run locally
+### Pull your image to run a local JupyterLab session
 ```
 export IMAGE=scottyhq/repo2docker-github
 export TAG=latest
@@ -36,7 +40,6 @@ docker stop repo2docker
 docker rm repo2docker
 ```
 
-### or run on a binderhub
-Just point to the image in a seperate repo containing notebooks you want to run:
+### Run your image on a BinderHub
+Now that you have images on DockerHub, you can re-use them in many ways. For example, create a BinderHub compatible content repository with 'binder' branch that points to a specific image. All your notebooks and scripts can be in the 'master' branch, and are pulled into a BinderHub session with [nbgitpuller](https://github.com/jupyterhub/nbgitpuller). Structuring things this way means that changes to your scripts won't trigger rebuilding large images:
 https://github.com/scottyhq/githubci-binder-example
-

binder/environment.yml

@@ -9,9 +9,7 @@ dependencies:
   - nbgitpuller=0.7
   - dask=2.8
   - distributed=2.8
-  - dask-kubernetes=0.10
   - dask-labextension=1.0
-  - dask-gateway=0.5
   - tornado=6.0
   - bokeh=1.4
   - python-graphviz=0.13

binder/postBuild.txt

@@ -6,8 +6,3 @@ jupyter labextension install dask-labextension \
                              @jupyter-widgets/jupyterlab-manager
 
 
-# dask config
-# ${KERNEL_PYTHON_PREFIX} is set by repo2docker to sys.prefix
-# of the python that the kernel is run in.
-mkdir -p ${KERNEL_PYTHON_PREFIX}/etc/dask
-cp binder/dask_config.yaml ${KERNEL_PYTHON_PREFIX}/etc/dask/dask.yaml