Installing plug-ins in a Docker image Custom images To install custom plug-ins or make other changes based on the DITA-OT parent image, you can create your own Dockerfile and specify the official DITA-OT image as the basis for your image. plug-ins installing in Docker images Docker images

Each subsequent declaration in the Dockerfile modifies this parent image, so you can start with the official image, and add custom plug-ins or other commands as required to create a custom Docker image that includes everything you need to publish your content.

 Create a new Dockerfile and specify the official DITA-OT image in the FROM directive. You can extend your image with a RUN declaration that runs the dita command from the container to install a custom plug-in, and specify the filename or URL of the plug-in’s distribution ZIP file. You can also install custom plug-ins from the main DITA-OT plug-in registry at , or from your company plug-in registry.

The docsrc/samples folder in the DITA-OT installation directory contains a complete example:

Sample Dockerfile with custom plug-ins: <filepath conkeyref="conref-task/samples-dir" /><filepath>/docker/Dockerfile</filepath> Building a new image

You can build a Docker image from this example by running the following command from the directory:

$ docker image build -t sample-docker-image:1.0 . Sending build context to Docker daemon 2.048kB Step 1/3 : FROM docker.pkg.github.com/dita-ot/dita-ot/dita-ot: ---> 9abb96827538 Step 2/3 : RUN dita --install https://github.com/infotexture/dita-bootstrap/archive/3.3.zip ---> Running in d510f874cae0 Added net.infotexture.dita-bootstrap Removing intermediate container d510f874cae0 ---> 63deb8e15b5b Step 3/3 : RUN dita --install org.dita-community.pdf-page-break ---> Running in b4ef2fcad916 Added org.dita-community.pdf-page-break Removing intermediate container b4ef2fcad916 ---> 402885636b7f Successfully built 402885636b7f Successfully tagged sample-docker-image:1.0

Docker steps through each instruction in the Dockerfile to build the sample image. In this case, the dita command provides feedback on each installed plug-in.

 Running the new container

You can then start a container based on your new image:

$ docker container run -it \ -v /path/to/dita-ot-dir/docsrc:/src sample-docker-image:1.0 \ -i /src/userguide.ditamap \ -o /src/out/dita-bootstrap \ -f html5-bootstrap -v

This command sequence specifies the following options:

  • mounts the docsrc subfolder of the DITA-OT directory on your host machine and binds it to the /src volume in the container
  • specifies /userguide.ditamap as the input map file
  • writes the output to /out/dita-bootstrap
  • sets the output format to the Bootstrap template, and
  • displays build progress messages with verbose logging

When the build is finished, you should find a copy of the DITA-OT documentation under /out/dita-bootstrap, styled with the basic Bootstrap template from the custom plug-in.