Vaadin & Spring Boot & WebSockets & OpenShift & Java8

Spring Boot is around for a while and because Vaadin caught my interest lately, plus Spring4Vaadin appeared, I gave it a spin. To make it more challenging, I decided to use Java 8 and deploy it on OpenShift. All the code is hosted on GitHub

Application is simple chat with OAuth2 sign in using Facebook/Google/GitHub/LinkedIn/Disqus. High-tech is way it broadcasts chat messages to chat participants using server push which in turn uses WebSocket mechanism.

Some informations about Spring Boot and OpenShift are part of the Spring Boot Documentation and some more in this blog post.

I've created DIY gear using OpenShift application console but same can be done using rhc app create vinbudin -t diy-0.1. Application code was already on GitHub and to get it running on OpenShift, following steps must be performed.

1. Add git upstream repository (openshift remote)

git clone git@github.com:anthavio/vinbudin.git
git remote add openshift ssh://your_uuid@vinbudin-yourdomain.rhcloud.com/~/git/vinbudin.git/

2. Add OpenShift build hooks

Build hooks in .openshift/action_hooks are shell scripts that are executed when you push something into OpenShift remote repository. Typically they stop application, run maven/ant/sbt to build application and start it again.

3. Push to the openshift

That's it. When you execute following command, you will see build hooks executed and project will be built and deployed on your openshift gear.

git push openshift master

You can still git push origin master to GitHub repository without invoking build on OpenShift

Maven 3.2.3 and Java 8 on OpenShift

OpenShift gears (28 Oct 2014) have only Java 1.7.0_71 and Maven 3.0.5. If you want to use different, most probably newer versions, just download and unpack them in .openshift/action_hooks/deploy into ${OPENSHIFT_DATA_DIR}

WebSockets on OpenShift

Situation seems to be same as two years ago when this blog post was written. You still have to access port 8000 to get WebSockets working.

Thanks to Vaadin/Atmosphere push implementation which automaticaly downgrade to long-polling when websockets mechanism is unavailable, user experience is not affected, but observing messages exchanged between browser and server, you will easily spot the problem.

Open Chrome Developer Tool Network tab and navigate to http://vinbudin-openshift.anthavio.net/ui

Request URL:ws://vinbudin-openshift.anthavio.net/ui/PUSH/?v-uiId=0&v-csrfToken=731062c6-712d-4320-a92c-3742fe3b4451&X-Atmosphere-tracking-id=0&X-Atmosphere-Framework=2.1.5.vaadin4-jquery&X-Atmosphere-Transport=websocket&X-Atmosphere-TrackMessageSize=true&X-Cache-Date=0&Content-Type=application/json;%20charset=UTF-8&X-atmo-protocol=true
Request Method:GET
Status Code:501 Not Implemented

WebSocket upgrade request was rejected. Ouch!

Now doing same, but with port 8000 in url - http://vinbudin-openshift.anthavio.net:8000/ui

Request URL:ws://vinbudin-openshift.anthavio.net:8000/ui/PUSH/?v-uiId=0&v-csrfToken=731062c6-712d-4320-a92c-3742fe3b4451&X-Atmosphere-tracking-id=0&X-Atmosphere-Framework=2.1.5.vaadin4-jquery&X-Atmosphere-Transport=websocket&X-Atmosphere-TrackMessageSize=true&X-Cache-Date=0&Content-Type=application/json;%20charset=UTF-8&X-atmo-protocol=true
Request Method:GET
Status Code:101 Switching Protocols

WebSocket upgrade request was accepted and protocol was switched. Hurray!

Happy Vaadin & Spring Boot & OpenShift websocketing!