Example Voting App

This application is a rewrite of https://github.com/dockersamples/example-voting-app We only use Java Vertx framework. In next releases, we will introduce other langages as Kotlin, Ceylon or JS. At this day, it is a nice proof-of-concept with the awesome Vertx.

Getting started

Download Docker. If you are on Mac or Windows, Docker Compose will be automatically installed. On Linux, make sure you have the latest version of Compose. Original post comes from there. We rewrote it with VertX.

Build the images in this directory:

mvn clean package docker:build

You should have a similar result with docker images:

 ✘ nicolas@MacBook > ~/software/vertx/vertx-voting-app > master > docker images 
REPOSITORY                              TAG                    IMAGE ID            CREATED             SIZE
vertxswarm/verticle-result             1.0-SNAPSHOT           ebeb1bb53f78        22 minutes ago      450 MB
vertxswarm/verticle-result             1.0-SNAPSHOT.27015db   ebeb1bb53f78        22 minutes ago      450 MB
vertxswarm/verticle-result             latest                 ebeb1bb53f78        22 minutes ago      450 MB
vertxswarm/verticle-worker             1.0-SNAPSHOT           fb702b8f68cf        40 minutes ago      440 MB
vertxswarm/verticle-worker             1.0-SNAPSHOT.27015db   fb702b8f68cf        40 minutes ago      440 MB
vertxswarm/verticle-worker             latest                 fb702b8f68cf        40 minutes ago      440 MB
vertxswarm/verticle-vote               1.0-SNAPSHOT           4b7a5532ba97        40 minutes ago      438 MB
vertxswarm/verticle-vote               1.0-SNAPSHOT.27015db   4b7a5532ba97        40 minutes ago      438 MB
vertxswarm/verticle-vote               latest                 4b7a5532ba97        40 minutes ago      438 MB

Run in this directory:

docker-compose up

The app will be running at:

You can use too if you update your /etc/hosts

Docker Swarm

Alternately, if you want to run it on a Docker Swarm, first make sure you have a swarm. If you don't, run:

Follow this guide to provision a local but complete environment with tutorial Local Docker Swarm.

You can directly use the Shell script

docker-machine create --driver virtualbox poc-manager
docker-machine ssh poc-manager "docker swarm init --advertise-addr $(docker-machine ip poc-manager)"
docker-machine create --driver virtualbox poc-worker1
docker-machine create --driver virtualbox poc-worker2
docker-machine ssh poc-worker1 "docker swarm join --token `docker $(docker-machine config poc-manager) swarm join-token worker -q` $(docker-machine ip poc-manager)"
docker-machine ssh poc-worker2 "docker swarm join --token `docker $(docker-machine config poc-manager) swarm join-token worker -q` $(docker-machine ip poc-manager)"

Once you have your swarm, in this directory run:

docker stack deploy --compose-file docker-stack.yml demo

Architecture

A verticle webapp which lets you vote between two options
A Redis queue which collects new votes
A verticle worker which consumes votes and stores them in…
A Postgres database backed by a Docker volume
A verticle webapp which shows the results of the voting in real time

Technical choice

We choose to use these Maven plugin :

For Verticle vote

For Verticle worker

For Verticle result

In a near future, we will update too :

Note

The voting application only accepts one vote per client. It does not register votes if a vote has already been submitted from a client.

Thanks to

Greetings to:

Vertx team
Guillaume Borg (from Treeptik)