README.md

Oracle Coherence Demonstration Application

Overview

This document describes how to build and run the Coherence Demonstration application. The application showcases Coherence general features, scalability capabilities, and new features of 14.1.1.0 version including:

• Cache Persistence
• Federation
• Java 8 Support
• OpenTracing Support

When you run the application locally, it results in a single self-contained JAR, javadoc and source.

The demonstration uses AngularJS 1.7.5, Bootstrap 3.3.4, and a number of other frameworks. The UI interacts with Coherence using the REST API.

Table of Contents

• Oracle Coherence Demonstration Application
  • Overview
  • Table of Contents
  • Prerequisites
    • General Prerequisites
    • Environment Variables
    • Coherence JARs
  • Run the Application Locally
    • Modify the Defaults
  • Run the Application on Kubernetes
  • References

Prerequisites

General Prerequisites

To run the demonstration application, you must have the following software installed:

1. Java 8 or 11 SE Development Kit or Runtime environment.

   You can download JDK 8 from:

   • Java SE Development Kit
   • JAVA SE Runtime Environment

   You can download JDK 11 from:

   • Java SE Development Kit 11 Downloads

2. Maven 3.5.4 or later version installed and configured.

3. Oracle Coherence 14.1.1.0.0 or later version installed.

   You can download it from http://www.oracle.com/technetwork/middleware/coherence/downloads/index.html.

   If you want to demonstrate the Coherence VisualVM plug-in, follow the instructions to install: https://docs.oracle.com/en/middleware/fusion-middleware/coherence/14.1.1.0/manage/using-jmx-manage-oracle-coherence.html

4. VisualVM is not included in JDK 11. You can download and install VisualVM from https://visualvm.github.io. You must provide -Dvisualvm.executable to point to the VisualVM executable.

5. Use a web browser that supports AngularJS to run the application. The following browsers are supported:

   • Safari, Chrome, Firefox, Opera 15, IE9 and mobile browsers (Android, Chrome Mobile, iOS Safari). For more information about browser compatibility, see https://code.angularjs.org/1.4.1/docs/misc/faq.

Note: All code compiles to JDK 8 bytecode for compatibility with Coherence releases.

Environment Variables

Ensure that the following environment variables are set in your configuation:

• JAVA_HOME -- This variable must point to the location of the JDK version supported by the Oracle Coherence version that you use. Ensure that the path is set accordingly:
  For Linux/UNIX OS:

export PATH=$JAVA_HOME/bin:$PATH

For Windows OS:

set PATH=%JAVA_HOME%\bin;%PATH%

• COHERENCE_HOME -- This variable must point to the \coherence directory of your Coherence installation. This is required for the Maven install-file commands.

• MAVEN_HOME -- If mvn command is not set in your PATH variable, then set MAVEN_HOME directed to the bin folder of Maven installation and then add MAVEN_HOME\bin to your PATH variable list.

Coherence JARs

You must have Coherence, Coherence-REST, and Coherence-JPA installed into your local maven repository. If not, execute the following commands with the version number of Coherence that you have installed in your configuration.

For Linux/UNIX/Mac OS:

mvn install:install-file -Dfile=$COHERENCE_HOME/lib/coherence.jar -DpomFile=$COHERENCE_HOME/plugins/maven/com/oracle/coherence/coherence/14.1.1/coherence.14.1.1.pom
mvn install:install-file -Dfile=$COHERENCE_HOME/lib/coherence-management.jar -DpomFile=$COHERENCE_HOME/plugins/maven/com/oracle/coherence/coherence-management/14.1.1/coherence-management.14.1.1.pom
mvn install:install-file -Dfile=$COHERENCE_HOME/lib/coherence-rest.jar -DpomFile=$COHERENCE_HOME/plugins/maven/com/oracle/coherence/coherence-rest/14.1.1/coherence-rest.14.1.1.pom
mvn install:install-file -Dfile=$COHERENCE_HOME/lib/coherence-http-netty.jar -DpomFile=$COHERENCE_HOME/plugins/maven/com/oracle/coherence/coherence-http-netty/14.1.1/coherence-http-netty.14.1.1.pom
mvn install:install-file -Dfile=$COHERENCE_HOME/lib/coherence-jpa.jar -DpomFile=$COHERENCE_HOME/plugins/maven/com/oracle/toplink/coherence-jpa/14.1.1/coherence-jpa-14.1.1.pom

For Windows OS:

mvn install:install-file -Dfile=%COHERENCE_HOME%\lib\coherence.jar -DpomFile=%COHERENCE_HOME%\plugins\maven\com\oracle\coherence\coherence\14.1.1\coherence.14.1.1.pom
mvn install:install-file -Dfile=%COHERENCE_HOME%\lib\coherence-management.jar -DpomFile=%COHERENCE_HOME%\plugins\maven\com\oracle\coherence\coherence-management\14.1.1\coherence-management.14.1.1.pom
mvn install:install-file -Dfile=%COHERENCE_HOME%\lib\coherence-rest.jar -DpomFile=%COHERENCE_HOME%\plugins\maven\com\oracle\coherence\coherence-rest\14.1.1\coherence-rest.14.1.1.pom
mvn install:install-file -Dfile=%COHERENCE_HOME%\lib\coherence-http-netty.jar -DpomFile=%COHERENCE_HOME%\plugins\maven\com\oracle\coherence\coherence-http-netty\14.1.1\coherence-http-netty.14.1.1.pom
mvn install:install-file -Dfile=%COHERENCE_HOME%\lib\coherence-jpa.jar -DpomFile=%COHERENCE_HOME%\plugins\maven\com\oracle\toplink\coherence-jpa\14.1.1\coherence-jpa.14.1.1.pom

OpenTracing Prerequisites

Prior to running the demo, start the Jaeger OpenTracing implementation:

docker run -d --name jaeger \
        -e COLLECTOR_ZIPKIN_HTTP_PORT=9411 \
        -p 5775:5775/udp \
        -p 6831:6831/udp \
        -p 6832:6832/udp \
        -p 5778:5778 \
        -p 16686:16686 \
        -p 14268:14268 \
        -p 9411:9411 \
        jaegertracing/all-in-one:1.13

Navigate to http://localhost:16686 in order to access the Jaeger UI.

Note: If Jaeger is already running in your environment locally, you can skip this step. If Jaeger is available at a different location, specify the JAEGER_ENDPOINT JVM property when starting the demo to override the default location.

Run the Application Locally

Build the application using Maven:

mvn clean install

The target directory contains a list of files:

 coherence-demo-{version}-SNAPSHOT.jar          - Executable JAR file, see instructions below
 coherence-demo-{version}-SNAPSHOT-javadoc.jar  - javadoc
 coherence-demo-{version}-SNAPSHOT-sources.jar  - sources

Run the JAR file in the target directory:

java -jar target/coherence-demo-3.0.1-SNAPSHOT.jar

If you are using JDK 11, use the following argument to start the VisualVM while running the JAR file:

java -Dvisualvm.executable=/u01/oracle/product/visualvm/visualvm_143/bin/visualvm -jar target/coherence-demo-3.0.1-SNAPSHOT.jar

-Dvisualvm.executable=/u01/oracle/product/visualvm/visualvm_143/bin/visualvm in the command points to the path of the VisualVM executable.

A Coherence Cache server and HTTP server are started on port 8080 for serving REST and application data. When the Cache server starts, the application loads on the default web browser at http://127.0.0.1:8080/application/index.html.

The following features are available to demonstrate in the application:

• Dynamically add or remove cluster members and observe the data repartition and recover automatically.
• Create and recover snapshots from the Persistence menu.
• Enable real-time price updates.
• Enable or disable indexes for queries.
• Add additional data, clear the cache or populate the cache from the Tools menu.
• Start VisualVM from the Tools menu.
• Start a secondary cluster from the Federation menu.
• Pause and resume replication to secondary cluster.
• Issue replicate all to secondary cluster.
• Open secondary cluster dashboard to observe changes are replicated.
• Stop Federation and shut down secondary cluster.

Note: If you recover a snapshot on a cluster, you must replicate all to resynchronize.

To shut down the application, select Shutdown option from the Tools menu. This shuts down all the processes including the secondary cluster if started.

Note: Secondary cluster will not form if you are running on a virtual private network due to security restrictions.

Modify the Defaults

HTTP Ports and Hostname

The default HTTP hostname is 127.0.0.1 and default port is 8080. To modify these you can add the http.hostname or http.port properties on startup:

java -Dhttp.hostname=myhostname -Dhttp.port=9000 -jar coherence-demo-3.0.1-SNAPSHOT.jar

By changing the http.hostname you can access the application outside of your local machine.

Default Cluster Names

When starting up the application, the timezone is analyzed and default names are selected for the primary and secondary cluster (see Launcher.java). If you want to customize the name, do the following:

java -Dprimary.cluster=NewYork -Dsecondary.cluster=Boston -jar coherence-demo-3.0.1-SNAPSHOT.jar

If you want to use a cluster name with a space, you must enclose it in quotes.

Run the Application on Kubernetes

The steps to run the application on Kubernetes comprises the following:

• Oracle Coherence Operator Helm Chart
• Use kubectl to install the Coherence cluster which comprises of 2 roles:
  • storage-enabled Coherence servers
  • storage-disabled application with Grizzly HTTP Server

Note: If you want to enable Federation when running on Kubernetes, see Enable Federation on Kubernetes.

1. Create Namespace

   Run the application using the Oracle Coherence Operator in a namespace called coherence-demo-ns. Create the demonstration namespace:

   kubectl create namespace coherence-demo-ns
   
   namespace/sample-coherence-ns created

2. Create Secret

   Create a secret for pulling the images from private repositories. For this application, create a secret named coehrence-demo-secret in the namespace coherence-demo-ns.

   kubectl create secret docker-registry coherence-demo-secret \
        --namespace coherence-demo-ns \
        --docker-server=your-docker-server \
        --docker-username=your-docker-username \
        --docker-email=your-email-address \
        --docker-password=your-docker-password

   Note: By default, the Docker details must be your Oracle Container Registry details.

   See https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/ for more information.

3. Build and Push Sidecar Docker Image

   Build and push the sidecar Docker image(optional). The Oracle Coherence Operator requires a sidecar Docker image to be built containing the classes and configuration files required by the application.

   Ensure that you have Docker running locally and execute the following command:

   mvn clean install -P docker

   This creates an image named coherence-demo-sidecar:3.0.1-SNAPSHOT which contains cache configuration and Java classes to be added to the classpath at runtime.

   Note: If you are running against a remote Kubernetes cluster, you need to push the sidecar Docker image to your repository accessible to that cluster. You also need to prefix the image name in your helm commands below.

4. Install the Oracle Coherence Operator

   Install the operator using helm:

   helm install \
      --namespace coherence-demo-ns \
      --set imagePullSecrets[0].name=coherence-demo-secret \
      --name coherence-operator \
      coherence/coherence-operator

   Confirm the creation of the chart:

   helm ls
   
   NAME              	REVISION	UPDATED                 	STATUS  	CHART                   	APP VERSION	NAMESPACE        
   coherence-operator	1       	Mon Oct 28 13:19:20 2019	DEPLOYED	coherence-operator-2.0.0	2.0.0      	coherence-demo-ns
   
   kubectl get pods --namespace coherence-demo-ns 
   
   NAME                                 READY   STATUS    RESTARTS   AGE
   coherence-operator-cd9b646d5-p5xk8   1/1     Running   0          2m12s

   To enable EFK (Elasticsearch, Fluentd and Kibana) integration to capture logs, see here.

   To enable metrics capture, see here

5. Install the Coherence Cluster

   The Coherence cluster comprises of 2 roles:

   • storage - contains the storage-enabled tier which stores application data
   • http - contains a storage-disabled http server which serves the application

   Create a file called demo-cluster.yaml containing the following:

   apiVersion: coherence.oracle.com/v1
   kind: CoherenceCluster
   metadata:
     name: primary-cluster
   spec:
     jvm:   
       memory:
         heapSize: 512m 
     imagePullSecrets:
       - name: coherence-example-secret 
     ports:
       - name: metrics
         port: 9612
     coherence:
       metrics:
         enabled: false  
       cacheConfig: cache-config.xml
     logging:
       fluentd:
         enabled: false    
     application:
       image: coherence-demo-sidecar:3.0.1-SNAPSHOT
     #
     # Individual cluster roles
     #
     roles:
       - role: storage
         replicas: 1  
         jvm:
           args:
             - "-Dwith.http=false"  
             - "-Dprimary.cluster=primary-cluster"
       - role: http
         replicas: 1  
         jvm:
           args:
             - "-Dprimary.cluster=primary-cluster"
         ports:
           - name: http
             port: 8080  
         coherence:
           storageEnabled: false

   Note: You can set metrics.enabled or fluentd.enabled to true if you have enabled this for the Coherence Operator install.

   kubectl create --namespace coherence-demo-ns -f demo-cluster.yaml

   Use kubectl get pods --namespace coherence-demo-ns to ensure that the pod is running. The pod primary-cluster-storage-0 must be running and ready as shown:

   NAME                                 READY   STATUS    RESTARTS   AGE
   coherence-operator-cd9b646d5-p5xk8   1/1     Running   0          33m
   primary-cluster-http-0               1/1     Running   0          3m2s
   primary-cluster-storage-0            1/1     Running   0          3m4s

   If the pod does not show as Running, you can use the following command to diagnose and troubleshoot the pod:

   kubectl describe pod primary-cluster-storage-0 --namespace coherence-demo-ns

6. Port Forward the HTTP Port

   kubectl port-forward --namespace coherence-demo-ns primary-cluster-http-0 8080:8080

7. Access the Application
   

   Use the following URL to access the application home page:

   http://127.0.0.1:8080/application/index.html

8. Scale the Application

   When running the application in Kubernetes, the Add Server and Remove Server options are not available. You need to use kubectl to scale the application.

   Scale the application to three nodes by editing demo-cluster.yaml and changing the replicas value for the storage role to 3. Then apply using

   kubectl apply --namespace coherence-demo-ns -f demo-cluster.yaml

   Use kubectl get pods --namespace coherence-demo-ns to view the progress.

9. Scale the Application down

   Scale the application to one node by editing demo-cluster.yaml and changing the replicas value for the storage role to 1. Then apply using

   kubectl apply --namespace coherence-demo-ns -f demo-cluster.yaml

   Use kubectl get pods --namespace coherence-demo-ns to view the scale down progress.

   Note: The Coherence Operator ensures that all scale operations are carried out in a safe manner (checking service statusHA values) to ensure no data is lost. You can confirm this by checking the number of positions are the same as before the scale-down was initiated.

10. Uninstall the Coherence Cluster

    Use the following to uninstall the Coherence cluster.

    kubectl delete --namespace coherence-demo-ns -f primary-cluster.yaml    

Enable Federation on Kubernetes

You must use Oracle Coherence 12.2.1.4.0 or later for Federation to work within Kubernetes.

The setup for this example uses two Coherence clusters in the same Kubernetes cluster. If you want to use Federation across Kubernetes cluster, see the Oracle Coherence Operator Samples.

• Primary Cluster
  • Cluster name: primary-cluster
• Secondary Cluster
  • Cluster name: secondary-cluster

Note: For this Federation example, the installation is simplified by using the storage-enabled pods to also serve the HTTP requests.

1. Create Namespace

   Run the application using the Oracle Coherence Operator in a namespace called coherence-demo-ns. Create the demonstration namespace:

   kubectl create namespace coherence-demo-ns
   
   namespace/sample-coherence-ns created

2. Create Secret

   Create a secret for pulling the images from private repositories. For this application, create a secret named coherence-demo-secret in the namespace coherence-demo-ns.

   kubectl create secret docker-registry coherence-demo-secret \
        --namespace coherence-demo-ns \
        --docker-server=your-docker-server \
        --docker-username=your-docker-username \
        --docker-email=your-email-address \
        --docker-password=your-docker-password

   Note: By default, the Docker details must be your Oracle Container Registry details. See https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/ for more information.

3. Build the sidecar image:

   mvn clean install -P docker

   Note: The coherence.version must be set to your installed Coherence version.

4. Install the Primary cluster:

   Create a file called primary-cluster.yaml containing the following:

   apiVersion: coherence.oracle.com/v1
   kind: CoherenceCluster
   metadata:
     name: primary-cluster
   spec:
     jvm:
       memory:
         heapSize: 512m 
     imagePullSecrets:
       - name: coherence-example-secret 
     ports:
       - name: metrics
         port: 9612      
       - name: federation
         port: 40000
     coherence:
       metrics:
         enabled: false 
       cacheConfig: cache-config.xml
     logging:
       fluentd:
         enabled: false    
     application:
       image: coherence-demo-sidecar:3.0.1-SNAPSHOT
     #
     # Individual cluster roles
     #
     roles:
       - role: storage
         replicas: 2  
         jvm:
           args:
             - "-Dwith.http=false"   
             - "-Dprimary.cluster=primary-cluster"
             - "-Dprimary.cluster.port=40000"
             - "-Dprimary.cluster.host=primary-cluster-wka"
             - "-Dsecondary.cluster=secondary-cluster"
             - "-Dsecondary.cluster.port=40000"
             - "-Dsecondary.cluster.host=secondary-cluster-wka"
       - role: http
         replicas: 1   
         jvm:
           args:
             - "-Dprimary.cluster=primary-cluster"   
             - "-Dprimary.cluster.host=primary-cluster-wka"
             - "-Dsecondary.cluster=secondary-cluster"  
             - "-Dsecondary.cluster.host=secondary-cluster-wka"
         ports:
           - name: http
             port: 8080  
         coherence:
           storageEnabled: false

   kubectl create --namespace coherence-demo-ns -f primary-cluster.yaml

   Use kubectl get pods --namespace coherence-demo-ns to ensure that the pods are running.

   NAME                                 READY   STATUS    RESTARTS   AGE
   coherence-operator-cd9b646d5-tzf2j   1/1     Running   0          58m
   primary-cluster-http-0               1/1     Running   0          74s
   primary-cluster-storage-0            1/1     Running   0          76s

5. Port forward the Primary Cluster - Port 8088

   kubectl port-forward --namespace coherence-demo-ns primary-cluster-http-0 8080:8080

   Use the following URL to access the application home page:

   http://127.0.0.1:8080/application/index.html

6. Install the Secondary cluster

   Create a file called secondary-cluster.yaml containing the following:

   apiVersion: coherence.oracle.com/v1
   kind: CoherenceCluster
   metadata:
     name: secondary-cluster
   spec:
     jvm:
       memory:
         heapSize: 512m 
     imagePullSecrets:
       - name: coherence-example-secret 
     ports:
       - name: metrics
         port: 9612      
       - name: federation
         port: 40000
     coherence:
       metrics:
        enabled: false
     logging:
       fluentd:
         enabled: false    
     application:
       image: coherence-demo-sidecar:3.0.1-SNAPSHOT
     #
     # Individual cluster roles
     #
     roles:
       - role: storage
         replicas: 2  
         jvm:
           args:
             - "-Dwith.http=false"   
             - "-Dwith.data=false"
             - "-Dprimary.cluster=primary-cluster"
             - "-Dprimary.cluster.port=40000"
             - "-Dprimary.cluster.host=primary-cluster-wka"
             - "-Dsecondary.cluster=secondary-cluster"
             - "-Dsecondary.cluster.port=40000"
             - "-Dsecondary.cluster.host=secondary-cluster-wka"
         coherence:
           cacheConfig: cache-config.xml
       - role: http
         replicas: 1   
         jvm:
           args:
             - "-Dprimary.cluster=primary-cluster"   
             - "-Dprimary.cluster.host=primary-cluster-wka"
             - "-Dsecondary.cluster=secondary-cluster"  
             - "-Dsecondary.cluster.host=secondary-cluster-wka"
         ports:
           - name: http
             port: 8080  
         coherence:
           cacheConfig: cache-config.xml
           storageEnabled: false

   kubectl create --namespace coherence-demo-ns -f secondary-cluster.yaml

   Use kubectl get pods --namespace coherence-demo-ns to ensure that the pods are running.

   NAME                                 READY   STATUS    RESTARTS   AGE
   coherence-operator-cd9b646d5-tzf2j   1/1     Running   0          78m
   primary-cluster-http-0               1/1     Running   0          2m
   primary-cluster-storage-0            1/1     Running   0          2m
   primary-cluster-storage-1            1/1     Running   0          2ms
   secondary-cluster-http-0             1/1     Running   0          70s
   secondary-cluster-storage-0          1/1     Running   0          72s
   secondary-cluster-storage-1          1/1     Running   0          72s

7. Port forward the Secondary Cluster - Port 8090

   kubectl port-forward --namespace coherence-demo-ns secondary-cluster-http-0 8090:8080

   Use the following URL to access the application home page:

   http://127.0.0.1:8090/application/index.html

   You can see that there is no data in the Secondary cluster as the Federation is not yet started.

8. Start Federation on the Primary Cluster

   In the Primary Cluster, select Start Federation from Federation menu. Access the Secondary Cluster dashboard and you can see the data appearing from the Primary Cluster.

9. Uninstall the Coherence Clusters

   kubectl delete --namespace coherence-demo-ns -f primary-cluster.yaml    
   
   kubectl delete --namespace coherence-demo-ns -f secondary-cluster.yaml   

Before starting another sample, ensure that all the pods are removed from the previous sample.

Uninstalling the Coherence Operator

To remove the coherence-operator, the use the following:

helm delete coherence-operator --purge

References

For more information about Oracle Coherence, see the following links:

• Download Coherence - http://www.oracle.com/technetwork/middleware/coherence/downloads/index.html
• Coherence Documentation - https://docs.oracle.com/en/middleware/fusion-middleware/coherence/14.1.1.0/index.html
• Coherence Community - http://coherence.oracle.com/