Need to know how to use Groovy to automate a Docker build & runtime - docker

Question

I have a task to containerize a Spring & React web-app so that non-technical staff can make use of the container to demo the app to clients. Currently we develop on OSX & deploy to Tomcat on AWS managed by a 3rd party firm, and the non-technical staff use Windows laptops for their stuff.
So far I have bash scripts in OSX which will create a Packager container that has a Java 8 SDK & maven installed, & which will compile the app into a war file. A second script creates and initializes a mongodb container & gives it a name, and the third script creates a Tomcat/Java 8 container, loads the war file into it, links it to the mongodb container & sets it running. In bash on OSX this works fine, but I found it didn't work if I tried it in cygwin on Windows 10, and my CMD/Powershell-fu is too weak to script it in a Windows native fashion.
So, I'm trying to do the script in something that'll run on both OSX, an AWS linux server & Windows 10, & being a Java developer myself I thought of Groovy. This is my first time scripting Docker using Groovy so I've ended up resorting to structures like:
println "docker build -f Dockerfile.packager -t mycontainer .".execute().text
I wonder if Docker has a Java or Groovy API that I could plug into & do things like:
docker.build("Dockerfile.packager").tag("mycontainer")
Currently my script is determining the location of the project root & building up the Docker run command as a string, like:
File emToo = new File(System.getProperty("user.dir")+"/.m2")
String currentDirectory = new File(".").getCanonicalPath()
String projectRoot = new File(currentDirectory+"/../").getCanonicalPath()
I get an option string from the user via a command line prompt, "Do you want QA or Dev?" & then:
String dockerRunCmd = "docker run -it -v $projectRoot/:/usr/local/build/myproject:cached -v ${emToo.getCanonicalPath()}:/root/.m2:cached mycontainer $option"
println dockerRunCmd.execute().text
Currently it doesn't seem to do anything after asking for the option - it's kinda bombing out. I get the run command output to screen, & if I copy/paste that into a command line in the scripts directory it falls over saying that the parent pom can't be found. Remember though that if I run the OSX bash script to do this, it works just fine. The bash script is basically:
#! /usr/bin/env bash
CWD=`pwd`
options=$1
docker run -it -v $CWD/../:/usr/local/build/myproject:cached -v ~/.m2:/root/.m2:cached --rm mycontainer $options
...which I think amounts to the same thing, right? Where's it going wrong?
UPDATE: I've found a bug - I should have been setting emToo to
new File(System.getProperty("user.home")+"/.m2"). user.dir just picks up the current directory, & the maven .m2 directory is in the user's home, usually. Currently though, the script gives me a run command that works if I cut/paste into a command line, but which doesn't allow me to call .execute() on the string in Groovy. If I can get that to work, there'll be no need for the docker-client projects suggested.

Answer 1

There are different ways to communicate with docker from groovy or java (sdk's are listed there https://docs.docker.com/engine/api/sdks/#other-languages):
Groovy (https://github.com/gesellix/docker-client)
Java (https://github.com/docker-java/docker-java)
Many others can be also found on github.
But as I see you are using maven so probably it will be easier for you to use awesome docker maven plugin (https://dmp.fabric8.io) which can build, push images, run containers etc.