Demo Java Web App

Simple java project demos how to build a war file to be deployed on a Tomcat server.

Build

The build script uses mvn package to produce a demo.war file and then bundles it with a Docker image that runs Tomcat. Usage:

bin/build

What happened

mvn package was ran and the target/demo.war was moved into pkg/demo.war
a docker image was built which copied the pkg/demo.war to /usr/local/tomcat/webapps/demo.war. Check out the Dockerfile for details.

Here's an example of some things to check after running the build script:

$ ls pkg/demo.war
pkg/demo.war
$ docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
demo-java           latest              88092dfb7325        6 minutes ago       591MB
tomcat              8.5                 a92c139758db        2 weeks ago         558MB
$

Source Url Mapping

The app is a small demo of a java servlet app. Here's the source code to url mapping:

Source	Url
src/main/java/Hello.java	localhost:8080/demo/Hello
src/main/webapp/index.jsp	localhost:8080/demo/index.jsp

Run

Here are the summarized commands to run and test that Tomcat is serving the war file:

docker run --rm -p 8080:8080 -d demo-java
docker exec -ti $(docker ps -ql) bash
curl localhost:8080/demo/Hello
curl localhost:8080/demo/index.jsp
exit
docker stop $(docker ps -ql)

Then you can hit the the [HOSTNAME]:8080/demo/Hello and to verify that Tomcat is servering the demo.war file. You should see an html page that says "Hello World". The output should look similar:

$ docker run --rm -p 8080:8080 -d demo-java
2ba7323481fa5c4068b90f2edf38555d9551303e9c2e4c27137ab0545688555b
$ docker exec -ti $(docker ps -ql) bash
root@2ba7323481fa:/usr/local/tomcat# curl localhost:8080/demo/Hello
<h1>Hello World Hello.java</h1>
root@2ba7323481fa:/usr/local/tomcat# curl localhost:8080/demo/index.jsp
<html>
<body>
<h2>Hello World index.jsp!</h2>
</body>
</html>
root@2ba7323481fa:/usr/local/tomcat# exit
exit
$ docker stop $(docker ps -ql)
2ba7323481fa
$ docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
$

Usage with UFO

The ufo branch of this project provides an additional demo that takes the war artifact, builds a Docker image and deploys it to ECS. For details please check out that branch: ufo. For more details on ufo check out the official ufo docs.

Initial Generation

Here are some notes on the initial generation of the project. The initial files and project structure was generated with the mvn archetype:generate command. Note, you do not have to run the command it is just noted here for posterity. More info: Creating a webapp and Introduction to the Standard Directory Layout.

Change were made like adding a simple Hello.java Serlvet class.

The original command was:

mvn archetype:generate \
  -DinteractiveMode=false \
  -DgroupId=com.domain \
  -DartifactId=demo \
  -DarchetypeArtifactId=maven-archetype-webapp

Dependencies

docker: brew install docker
maven: brew install maven

emanoel2712 / demo-java