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Upstream ENV overrides?


If I’d like for instance to create my own tomcat docker build using an official tomcat docker image, am I forced to accept what an upstream developer has set for an ENV variable in their Dockerfile?

e.g. if I’d like to override the value of CATALINA_HOME from /usr/local/tomcat > /home/user/foo/bar/another

Can I do this in my Dockerfile in a way that overrides what was set in the image I’m basing my Dockerfile off of so that the dockerbuild process uses the path I wish so that the tomcat folder is built to /home/user/foo/bar/another/tomcat ?

e.g this doesn’t work in the sense of influencing the build process upstream

FROM tomcat:8.5.54-jdk8-openjdk

ENV CATALINA_HOME /home/user/foo/bar/another

CMD ["", "run"]

Thanks in advance for any guidance as I’m new to learning Docker.