websocket-endpoint: Web application using WebSockets and JSON-P

Shows how to use WebSockets with JSON to broadcast information to all open WebSocket sessions in WildFly.

What is it?

The websocket-endpoint quickstart demonstrates how to use Java API for WebSockets to create server endpoints in WildFly Application Server.

The BidWebSocketEndpoint provides the WebSocket endpoint that receives Message instances from clients/browsers and replies with the current Bidding instance. The conversion from JSON content to the specific instances are made by MessageDecoder and BiddingEncode classes.

Every update made on the Bidding are immediately propagated to all opened WebSocket sessions without any browser submission or AJAX polling mechanism.

Browse the source

System Requirements

The application this project produces is designed to be run on WildFly Application Server 33 or later.

All you need to build this project is Java 11.0 (Java SDK 11) or later and Maven 3.6.0 or later. See Configure Maven to Build and Deploy the Quickstarts to make sure you are configured correctly for testing the quickstarts.

Use of the WILDFLY_HOME and QUICKSTART_HOME Variables

In the following instructions, replace WILDFLY_HOME with the actual path to your WildFly installation. The installation path is described in detail here: Use of WILDFLY_HOME and JBOSS_HOME Variables.

When you see the replaceable variable QUICKSTART_HOME, replace it with the path to the root directory of all of the quickstarts.

Building and running the quickstart application with a WildFly server distribution

Start the WildFly Standalone Server

Open a terminal and navigate to the root of the WildFly directory.
Start the WildFly server with the default profile by typing the following command.
```
$ WILDFLY_HOME/bin/standalone.sh 
```
Note
For Windows, use the WILDFLY_HOME\bin\standalone.bat script.

Build and Deploy the Quickstart

Make sure WildFly server is started.
Open a terminal and navigate to the root directory of this quickstart.
Type the following command to build the quickstart.
```
$ mvn clean package
```
Type the following command to deploy the quickstart.
```
$ mvn wildfly:deploy
```

This deploys the websocket-endpoint/target/websocket-endpoint.war to the running instance of the server.

You should see a message in the server log indicating that the archive deployed successfully.

Access the Application

Access the running application in a browser at the following URL: http://localhost:8080/websocket-endpoint/.

You are presented with a simple form that shows a bidding with the status NOT_STARTED.

Click on Do a bid! button. That will start the bidding and trigger the 1 minute countdown timer. You can also notice that every Bid will be listed under the List of bids section.

You should open the application URL in other browsers or tabs. You will notice that every change on the bidding is automatically update in all opened browser or tabs. The item will be SOLD once that it reaches the Buy now price. At the countdown timeout, the bidding will be EXPIRED. You can click on Buy it now button to immediately buy the item.

You can restart the bidding if you click on Reset bidding button.

Run the Integration Tests

This quickstart includes integration tests, which are located under the src/test/ directory. The integration tests verify that the quickstart runs correctly when deployed on the server.

Follow these steps to run the integration tests.

Make sure WildFly server is started.
Make sure the quickstart is deployed.
Type the following command to run the verify goal with the integration-testing profile activated.
```
$ mvn verify -Pintegration-testing 
```

Undeploy the Quickstart

When you are finished testing the quickstart, follow these steps to undeploy the archive.

Make sure WildFly server is started.
Open a terminal and navigate to the root directory of this quickstart.
Type this command to undeploy the archive:
```
$ mvn wildfly:undeploy
```

Building and running the quickstart application with provisioned WildFly server

Instead of using a standard WildFly server distribution, you can alternatively provision a WildFly server to deploy and run the quickstart, by activating the Maven profile named provisioned-server when building the quickstart:

$ mvn clean package -Pprovisioned-server

The provisioned WildFly server, with the quickstart deployed, can then be found in the target/server directory, and its usage is similar to a standard server distribution, with the simplification that there is never the need to specify the server configuration to be started.

The server provisioning functionality is provided by the WildFly Maven Plugin, and you may find its configuration in the quickstart pom.xml:

        <profile>
            <id>provisioned-server</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.wildfly.plugins</groupId>
                        <artifactId>wildfly-maven-plugin</artifactId>
                        <configuration>
                            <discover-provisioning-info>
                                <version>${version.server}</version>
                            </discover-provisioning-info>
                            <!--
                                Rename the output war to ROOT.war before adding it to the server, so that the
                                application is deployed in the root web context.
                            -->
                            <name>ROOT.war</name>
                            <add-ons>...</add-ons>
                        </configuration>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>package</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                    ...
                </plugins>
            </build>
        </profile>

The plugin uses WildFly Glow to discover the feature packs and layers required to run the application, and provisions a server containing those layers.

If you get an error or the server is missing some functionality which cannot be auto-discovered, you can download the WildFly Glow CLI and run the following command to see more information about what add-ons are available:

wildfly-glow show-add-ons

Note	Since the plugin configuration above deploys quickstart on root web context of the provisioned server, the URL to access the application should not have the `/websocket-endpoint` path segment after `HOST:PORT`.

Run the Integration Tests with a provisioned server

The integration tests included with this quickstart, which verify that the quickstart runs correctly, may also be run with a provisioned server.

Follow these steps to run the integration tests.

Make sure the server is provisioned.

$ mvn clean package -Pprovisioned-server

Start the WildFly provisioned server, this time using the WildFly Maven Plugin, which is recommended for testing due to simpler automation. The path to the provisioned server should be specified using the jbossHome system property.
```
$ mvn wildfly:start -DjbossHome=target/server 
```
Type the following command to run the verify goal with the integration-testing profile activated, and specifying the quickstart’s URL using the server.host system property, which for a provisioned server by default is http://localhost:8080.
```
$ mvn verify -Pintegration-testing -Dserver.host=http://localhost:8080 
```
Shutdown the WildFly provisioned server, this time using the WildFly Maven Plugin too.
```
$ mvn wildfly:shutdown
```

Building and running the quickstart application with OpenShift

Build the WildFly Source-to-Image (S2I) Quickstart to OpenShift with Helm Charts

On OpenShift, the S2I build with Apache Maven uses an openshift Maven profile to provision a WildFly server, deploy and run the quickstart in OpenShift environment.

The server provisioning functionality is provided by the WildFly Maven Plugin, and you may find its configuration in the quickstart pom.xml:

        <profile>
            <id>openshift</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.wildfly.plugins</groupId>
                        <artifactId>wildfly-maven-plugin</artifactId>
                        <configuration>
                            <discover-provisioning-info>
                                <version>${version.server}</version>
                                <context>cloud</context>
                            </discover-provisioning-info>
                            <!--
                                The parent POM's 'openshift' profile renames the output archive to ROOT.war so that the
                                application is deployed in the root web context. Add ROOT.war to the server.
                            -->
                            <filename>ROOT.war</filename>
                            <add-ons>...</add-ons>
                        </configuration>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>package</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                    ...
                </plugins>
            </build>
        </profile>

You may note that unlike the provisioned-server profile it uses the cloud context which enables a configuration tuned for OpenShift environment.

The plugin uses WildFly Glow to discover the feature packs and layers required to run the application, and provisions a server containing those layers.

wildfly-glow show-add-ons

Getting Started with WildFly for OpenShift and Helm Charts

This section contains the basic instructions to build and deploy this quickstart to WildFly for OpenShift or WildFly for OpenShift Online using Helm Charts.

Prerequisites

You must be logged in OpenShift and have an oc client to connect to OpenShift
Helm must be installed to deploy the backend on OpenShift.

Once you have installed Helm, you need to add the repository that provides Helm Charts for WildFly.

$ helm repo add wildfly https://docs.wildfly.org/wildfly-charts/
"wildfly" has been added to your repositories
$ helm search repo wildfly
NAME                    CHART VERSION   APP VERSION     DESCRIPTION
wildfly/wildfly         ...             ...            Build and Deploy WildFly applications on OpenShift
wildfly/wildfly-common  ...             ...            A library chart for WildFly-based applications

Deploy the WildFly Source-to-Image (S2I) Quickstart to OpenShift with Helm Charts

Log in to your OpenShift instance using the oc login command. The backend will be built and deployed on OpenShift with a Helm Chart for WildFly.

Navigate to the root directory of this quickstart and run the following command:

$ helm install websocket-endpoint -f charts/helm.yaml wildfly/wildfly --wait --timeout=10m0s 
NAME: websocket-endpoint
...
STATUS: deployed
REVISION: 1

This command will return once the application has successfully deployed. In case of a timeout, you can check the status of the application with the following command in another terminal:

oc get deployment websocket-endpoint

The Helm Chart for this quickstart contains all the information to build an image from the source code using S2I on Java 17:

build:
  uri: https://github.com/wildfly/quickstart.git
  ref: main
  contextDir: websocket-endpoint
deploy:
  replicas: 2

This will create a new deployment on OpenShift and deploy the application.

If you want to see all the configuration elements to customize your deployment you can use the following command:

$ helm show readme wildfly/wildfly

Get the URL of the route to the deployment.

$ oc get route websocket-endpoint -o jsonpath="{.spec.host}"

Access the application in your web browser using the displayed URL.

Note	The Maven profile named `openshift` is used by the Helm chart to provision the server with the quickstart deployed on the root web context, and thus the application should be accessed with the URL without the `/websocket-endpoint` path segment after `HOST:PORT`.

Run the Integration Tests with OpenShift

The integration tests included with this quickstart, which verify that the quickstart runs correctly, may also be run with the quickstart running on OpenShift.

Note	The integration tests expect a deployed application, so make sure you have deployed the quickstart on OpenShift before you begin.

Run the integration tests using the following command to run the verify goal with the integration-testing profile activated and the proper URL:

$ mvn verify -Pintegration-testing -Dserver.host=https://$(oc get route websocket-endpoint --template='{{ .spec.host }}')

Note	The tests are using SSL to connect to the quickstart running on OpenShift. So you need the certificates to be trusted by the machine the tests are run from.

Undeploy the WildFly Source-to-Image (S2I) Quickstart from OpenShift with Helm Charts

$ helm uninstall websocket-endpoint

Building and running the quickstart application with Kubernetes

Build the WildFly Quickstart to Kubernetes with Helm Charts

For Kubernetes, the build with Apache Maven uses an openshift Maven profile to provision a WildFly server, suitable for running on Kubernetes.

The server provisioning functionality is provided by the WildFly Maven Plugin, and you may find its configuration in the quickstart pom.xml:

        <profile>
            <id>openshift</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.wildfly.plugins</groupId>
                        <artifactId>wildfly-maven-plugin</artifactId>
                        <configuration>
                            <discover-provisioning-info>
                                <version>${version.server}</version>
                                <context>cloud</context>
                            </discover-provisioning-info>
                            <!--
                                The parent POM's 'openshift' profile renames the output archive to ROOT.war so that the
                                application is deployed in the root web context. Add ROOT.war to the server.
                            -->
                            <filename>ROOT.war</filename>
                            <add-ons>...</add-ons>
                        </configuration>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>package</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                    ...
                </plugins>
            </build>
        </profile>

You may note that unlike the provisioned-server profile it uses the cloud context which enables a configuration tuned for Kubernetes environment.

The plugin uses WildFly Glow to discover the feature packs and layers required to run the application, and provisions a server containing those layers.

wildfly-glow show-add-ons

Getting Started with Kubernetes and Helm Charts

This section contains the basic instructions to build and deploy this quickstart to Kubernetes using Helm Charts.

Install Kubernetes

In this example we are using Minikube as our Kubernetes provider. See the Minikube Getting Started guide for how to install it. After installing it, we start it with 4GB of memory.

minikube start --memory='4gb'

The above command should work if you have Docker installed on your machine. If, you are using Podman instead of Docker, you will also need to pass in --driver=podman, as covered in the Minikube documentation.

Once Minikube has started, we need to enable its registry since that is where we will push the image needed to deploy the quickstart, and where we will tell the Helm charts to download it from.

minikube addons enable registry

In order to be able to push images to the registry we need to make it accessible from outside Kubernetes. How we do this depends on your operating system. All the below examples will expose it at localhost:5000

# On Mac:
docker run --rm -it --network=host alpine ash -c "apk add socat && socat TCP-LISTEN:5000,reuseaddr,fork TCP:$(minikube ip):5000"

# On Linux:
kubectl port-forward --namespace kube-system service/registry 5000:80 &

# On Windows:
kubectl port-forward --namespace kube-system service/registry 5000:80
docker run --rm -it --network=host alpine ash -c "apk add socat && socat TCP-LISTEN:5000,reuseaddr,fork TCP:host.docker.internal:5000"

Prerequisites

Helm must be installed to deploy the backend on Kubernetes.

Once you have installed Helm, you need to add the repository that provides Helm Charts for WildFly.

$ helm repo add wildfly https://docs.wildfly.org/wildfly-charts/
"wildfly" has been added to your repositories
$ helm search repo wildfly
NAME                    CHART VERSION   APP VERSION     DESCRIPTION
wildfly/wildfly         ...             ...            Build and Deploy WildFly applications on OpenShift
wildfly/wildfly-common  ...             ...            A library chart for WildFly-based applications

Deploy the WildFly Source-to-Image (S2I) Quickstart to Kubernetes with Helm Charts

The backend will be built and deployed on Kubernetes with a Helm Chart for WildFly.

Navigate to the root directory of this quickstart and run the following commands:

mvn -Popenshift package wildfly:image

This will use the openshift Maven profile we saw earlier to build the application, and create a Docker image containing the WildFly server with the application deployed. The name of the image will be websocket-endpoint.

Next we need to tag the image and make it available to Kubernetes. You can push it to a registry like quay.io. In this case we tag as localhost:5000/websocket-endpoint:latest and push it to the internal registry in our Kubernetes instance:

# Tag the image
docker tag websocket-endpoint localhost:5000/websocket-endpoint:latest
# Push the image to the registry
docker push localhost:5000/websocket-endpoint:latest

In the below call to helm install which deploys our application to Kubernetes, we are passing in some extra arguments to tweak the Helm build:

--set build.enabled=false - This turns off the s2i build for the Helm chart since Kubernetes, unlike OpenShift, does not have s2i. Instead, we are providing the image to use.
--set deploy.route.enabled=false - This disables route creation normally performed by the Helm chart. On Kubernetes we will use port-forwards instead to access our application, since routes are an OpenShift specific concept and thus not available on Kubernetes.
--set image.name="localhost:5000/websocket-endpoint" - This tells the Helm chart to use the image we built, tagged and pushed to Kubernetes' internal registry above.

$ helm install websocket-endpoint -f charts/helm.yaml wildfly/wildfly --wait --timeout=10m0s --set build.enabled=false --set deploy.route.enabled=false --set image.name="localhost:5000/websocket-endpoint"
NAME: websocket-endpoint
...
STATUS: deployed
REVISION: 1

This command will return once the application has successfully deployed. In case of a timeout, you can check the status of the application with the following command in another terminal:

kubectl get deployment websocket-endpoint

The Helm Chart for this quickstart contains all the information to build an image from the source code using S2I on Java 17:

build:
  uri: https://github.com/wildfly/quickstart.git
  ref: main
  contextDir: websocket-endpoint
deploy:
  replicas: 2

This will create a new deployment on Kubernetes and deploy the application.

If you want to see all the configuration elements to customize your deployment you can use the following command:

$ helm show readme wildfly/wildfly

To be able to connect to our application running in Kubernetes from outside, we need to set up a port-forward to the websocket-endpoint service created for us by the Helm chart.

This service will run on port 8080, and we set up the port forward to also run on port 8080:

kubectl port-forward service/websocket-endpoint 8080:8080

The server can now be accessed via http://localhost:8080 from outside Kubernetes. Note that the command to create the port-forward will not return, so it is easiest to run this in a separate terminal.

Note	The Maven profile named `openshift` is used by the Helm chart to provision the server with the quickstart deployed on the root web context, and thus the application should be accessed with the URL without the `/websocket-endpoint` path segment after `HOST:PORT`.

Run the Integration Tests with Kubernetes

The integration tests included with this quickstart, which verify that the quickstart runs correctly, may also be run with the quickstart running on Kubernetes.

Note	The integration tests expect a deployed application, so make sure you have deployed the quickstart on Kubernetes before you begin.

Run the integration tests using the following command to run the verify goal with the integration-testing profile activated and the proper URL:

$ mvn verify -Pintegration-testing -Dserver.host=http://localhost:8080

Undeploy the WildFly Source-to-Image (S2I) Quickstart from Kubernetes with Helm Charts

$ helm uninstall websocket-endpoint

To stop the port forward you created earlier use:

$ kubectl port-forward service/websocket-endpoint 8080:8080