Deploying Java webapp to Tomcat 8 running in Docker container

I am pretty new to Tomcat and Docker - so I am probably missing a Tomcat fundamental somewhere in this question.

What I am trying to do is build a Docker container that runs a SpringBoot Restful web service that just returns some static data. This is all running on OSX so I am using Boot2Docker as well.

I've written my own Dockerfile to build the container that my app runs in:

FROM tomcat:8.0.20-jre8

RUN mkdir /usr/local/tomcat/webapps/myapp

COPY /1.0-SNAPSHOT/my-app-1.0-SNAPSHOT.war /usr/local/tomcat/webapps/myapp/

This Dockerfile works fine and I am able to start the container from the created image.

docker build -t myapp .

docker run -it --rm -p 8888:8080 myapp

This container starts correctly and outputs no errors and displays the message saying my app was deployed.

22-Mar-2015 23:07:21.217 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory 
Deploying web application directory /usr/local/tomcat/webapps/myapp

The container also correctly has the myapp.war copied to the path described in the Dockerfile. Moreover I am able to navigate to Tomcat default page to confirm that Tomcat is running, I can also hit all the examples, etc.

To the problem, when I navigate to http://192.168.59.103:8888/myapp/getData I get a 404. I can't quite figure out why. Am I missing something regarding a .war deploy to Tomcat?

You are trying to copy the war file to a directory below webapps. The war file should be copied into the webapps directory.

Remove the mkdir command, and copy the war file like this:

COPY /1.0-SNAPSHOT/my-app-1.0-SNAPSHOT.war /usr/local/tomcat/webapps/myapp.war

Tomcat will extract the war if autodeploy is turned on.

There's a oneliner for this one.

You can simply run,

docker run -v /1.0-SNAPSHOT/my-app-1.0-SNAPSHOT.war:/usr/local/tomcat/webapps/myapp.war -it -p 8080:8080 tomcat

This will copy the war file to webapps directory and get your app running in no time.

Tomcat will only extract the war which is copied to webapps directory. Change Dockerfile as below:

FROM tomcat:8.0.20-jre8
COPY /1.0-SNAPSHOT/my-app-1.0-SNAPSHOT.war /usr/local/tomcat/webapps/myapp.war

You might need to access the url as below unless you have specified the webroot

http://192.168.59.103:8888/myapp/getData