Dockerfile for using the scrollphat library without needing to install it on base system.

To learn how to install Docker on a Pi visit:

• Hands-on Docker for Raspberry Pi

For a curated collection of tutorials and images for Docker on ARM (Raspberry Pi) visit:

• https://github.com/alexellis/docker-arm

Building:

Build the local source as a Docker image:

$ ./build_docker.sh

Or build from the master branch on Github with:

$ ./build_docker_git.sh

Running in a REPL

Note: i2c interfaces must be enabled on the Raspberry Pi host. See raspi-config for more info

$ docker run -ti --privileged scroll-phat

Python 2.7.9 (default, Mar  8 2015, 00:52:26)
[GCC 4.9.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import scrollphat
>>> scrollphat.set_pixel(1,1,True)
>>> scrollphat.update()
>>>

Adding your own code

Build an image to run an example file:

Dockerfile

FROM scroll-phat
CMD ["python", "examples/count.py", "99"]

Build example

docker build -t scroll-phat/count .

Running an example

docker run --privileged scroll-phat/count

Use-cases for Docker

Testing use-case

• Remove all traces of scroll-phat egg from base system

• Use Dockerfile to run setup.py install then run a number of the examples to see whether they are working fully.

• Can easily have an image with only Python2, only Python3 and both - for testing.

Previously this would have involved hacks and work-arounds.

Deployment use-case

• Once i2c is configured on the base system, nothing needs to be installed on top at all
• Everything can be installed straight into the image - even at different versions
• Can be used as a base image to be derived from for a personal project with scroll-phat

Can be used to distribute a tested/working installation

Maintainer builds image -> maintainer uploads to Docker Hub -> consumer/enthusiast pulls image, runs exactly the same as it did for the maintainer.