process-monitor

Process monitor sample

This example contains a process monitor that shows the top 10 processes that are running on the server on different clients. The sample is based on the remoting modules of Dolphin Platform. By doing so data can easily synchronized between client and server.

The application provides several clientsthat are all connected to the same server instance. All clients will show an automatically updating list of the top 10 processes that are running on the server. Even the web clients will show a live view in the browser with no need of doing a page refresh.

How are the automatic view updated implemented?

This sample is based on top of the Dolphin Platform remoting layer. This API implements the remote presentation model pattern. In the remoting layer, all models will automatically be synchronized between client and server. Thus, you don't need to think about any specific endpoints or requests.

Based on this, the remoting layer defines server side controllers that contain all the controller logic for a specific view. The lifecycle of these controllers is automatically synchronized with the view lifecycle. With this approach you have a MVC group for each client view with a synchronized model and a managed controller.

To allow dynamic updates from the client and the server the remoting layer of the Dolphin Platform uses interruptable long polling for communication. By doing so both sides can easily send updates.

In the given example a background thread on the server checks the cpu top of the machine and provides an update task to the remoting layer that will automatically be called with the next long poll. If for the given client a long poll is currently running it will be directly called.

Modules

The sample is seperated in several modules. The following image shows the dependecies of the modules:

For all Java modules the model of the application is defined in the common module. By doing so the module definition can easily be shared between client and server modules. The server-base module contains all classes that are "server framework agnostic" and can easily be used in JavaEE and Spring.

Start the sample

The sample provide a JavaEE and a Spring based server. Only one of the servers can be started since both use the same port. The server provides the application at http://localhost:8080/process-monitor.

Once a server is running multiple instances of the clients can be started. All clients connect to a server at http://localhost:8080/process-monitor.

All modules provide a Maven target to start the application.

JavaEE server

To start the JavaEE server simply run mvn wildfly:run from the server-javaee folder. Next to this the server can be deployed to any JavaEE 6 application server. To do so run mvn verify from the server-javaee folder. The created process-monitor.war in the target folder can be deployed as JavaEE web application. The application must be reachable under http://localhost:8080/process-monitor.

Spring Boot server

To start the Spring Boot server simply run mvn spring-boot:run from the server-spring folder. Next to this the server can be started by the com.canoo.dolphin.samples.processmonitor.ProcessMonitorServer class.

JavaFX client

To start the JavaFX client simply run mvn jfx:run from the client-javafx folder. Next to this the client can be started by the com.canoo.dolphin.samples.processmonitor.ProcessMonitorClient class.

Angular client

To start the Angular client simply run mvn jetty:run from the client-angular folder. Once this is done the client can be reached at http://localhost:8081. Just open this url in any web browser.

By calling mvn jetty:run the following will happen:

• NPM will be installed locally in the module folder.
• npm install will be called in the folder. By doing so NPM will install bower
• bower install will be called in the folder. This will download all needed dependencies for the client.
• A Jetty instance will be started. This will host the client at http://localhost:8081

Polymer client

To start the Polymer client simply run mvn jetty:run from the client-polymer folder. Once this is done the client can be reached at http://localhost:8082. Just open this url in any web browser.

By calling mvn jetty:run the following will happen:

• NPM will be installed locally in the module folder.
• npm install will be called in the folder. By doing so NPM will install bower
• bower install will be called in the folder. This will download all needed dependencies for the client.
• A Jetty instance will be started. This will host the client at http://localhost:8082

License

The project is released as open source under the Apache License Version 2.0

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