Spring Boot for the Web Tier

Introduction

This is code from the ``Spring Boot for the Web Tier'' presentation given at SpringOne 2014. It demonstrates a number of Spring Boot features that are particularly relevant to web developers.

Use git log to see how the application was constructed and git reset --hard if you want to go back to a particular point in time.

Credits

This demonstration uses CSS and Javascript from the ``Text Opening Sequence with CSS Animations'' article by Mary Lou. It also uses Jars from the webjars project.

Building and running the code

This project can be build using Apache Maven from the root directory:

$ mvn clean package

Once build code can be run using java -jar:

$ java -jar target/spring-boot-for-the-web-tier.jar

There are a couple of Firefox plugins that also help: * https://addons.mozilla.org/en-US/firefox/addon/empty-cache-button/ * https://github.com/nohamelin/simple-locale-switcher

In addition, if you want to run the Apache HTTP SSL demo you will need docker (see instructions below).

Demos

Static Content

Static content is served from src/main/resources/public. You can see an index.html file which is automatically mapped to http://localhost:8080/. You can also see how a custom src/main/resources/favicon.ico file can be used.

Additional this project demonstrates how jQuery can be loaded from a `webjar'' and how wro4j can be used to process a `less css file.

Dynamic Content

The /hello/{name} endpoint demonstrates how dynamic content can be created using Groovy templates. It also shows internationalization using Spring’s MessageSource interface.

The /convert endpoint shows how a custom HttpMessageConverter can be used. Notice that ExampleRestController returns a list, which is converted by ListHttpMessageConverter. If you comment out the @Component annotation from ListHttpMessageConverter you’ll see a standard JSON response instead.

HTTPD Proxy

The /whoami endpoint can be used to show how Apache HTTPD can be used as an SSL terminating proxy in front of a Spring Boot application. For convenience a dockerfile is provided to create a configured HTTPD installation.

To build the docker image:

$ docker build -t springone/httpd-proxy httpd-docker

When running image you need to ensure that a TOMCAT_HOST environment variable has been set to the IP address of your local machine. The following commands should work on most machines:

$ export TOMCAT_HOST=$(ifconfig | sed -En '/docker/,+2d;s/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p' | head -n 1)
$ docker run -i -d -p 8081:80 -p 8082:443 -e TOMCAT_HOST springone/httpd-proxy

If you have problems check that TOMCAT_HOST has the correct IP address.

To test the application you can first curl directly to your running application:

$ curl http://127.0.0.1:8080/whoami
$ curl -k https://127.0.0.1:8080/whoami

The first command should return http://127.0.0.1:8080, the second should fail because SSL hasn’t been configured.

To test via the HTTPD proxy:

$ curl http://127.0.0.1:8081/whoami
$ curl -k http://127.0.0.1:8082/whoami

or if you’re on a mac using boot2docker:

$ curl http://$(boot2docker ip 2>/dev/null):8081/whoami
$ curl -k https://$(boot2docker ip 2>/dev/null):8082/whoami

This time you should see a different IP address and the second command should report a https:// address.