Provide docker image

[kdeininger]

Description

This PR provides a Docker image to run citygml-tools inside a container without installing any Java dependencies on the host. Please feel free to use this image and publish it on an image registry of your choice.

Technical details

It uses Alpine Linux to keep the resulting images small. Additionally, it is written as multi-stage image, which means the "JDK image" is only used for building, while the final application gets wrapped in a smaller "JRE image".

By default, the container process is executed as non-root user. The included entrypoint script allows the image also to be used in OpenShift environments, where an arbitrary user might be created on container start.

The default working directory inside the container is /data.

Usage

1. Build the image, e.g.

   docker build -t citygml-tools .

2. By default, running the container shows the help message

   docker run --rm citygml-tools

3. Mount a volume and run any other citycml-tools command, e.g.

   docker run --rm -u 1000 -v /my/cityjson/data:/data citygml-tools from-cityjson /data

   Notes:

   • In this case, citygml-tools is the name of the image.
   • Use the -u parameter to pass the user ID of your current host's user to set the right permissions on generated files in the mounted directory.

[clausnagel]

Great work, thanks for your contribution! I am not too familiar with registering docker images. Can you recommend an image registry?

[kdeininger]

Thanks for your reply!

There are many registries available to host container images. I would recommend one of the following:

• https://hub.docker.com/ (official Docker registry, free for public images, most popular)
• https://quay.io/ (RedHat container registry, free for public images, more secure due to vulnerability scans)
• GitHub Packages (I have not used it until now, but it should be easy to set up with the existing repository)

Maybe you should give GitHub Packages a try. Please let me know, if you need further information.