spring-boot-plugins-example

An example of building a spring-boot application extendable with plugins.

Plugins? Why not osgi?

This approach has some weak points:

• There is not separation between the plugins, its just all on one classpath at runtime. So be careful if you import dependencies in a plugin - they my conflict with the ones from another plugin
• You can only install plugins before you start the application, not at runtime
• You can not remove or update plugins at runtime

But if you can live with this, it has some advantages too:

• No osgi runtime needed
• One plugin can totally use the other. An extension of the database like the team plugin is not possible with osgi bundles AFAIK
• Simply use spring in all parts of your application

Description

This demo uses vaadin for the UI and spring-data-jpa with geodb and hibernate for persistence.

Usage

1. Clone the reopsitory
2. Build the stuff mvn install
3. Start the application: cd application/target and then: java -jar application-0.0.1-SNAPSHOT.jar

Now the application starts just with the people plugin. To add the team plugin:

1. Stop the application
2. Create a folder called lib next to application-0.0.1-SNAPSHOT.jar and place plugin-team-0.0.1-SNAPSHOT.jar in it.
3. Start the application again

Now the application starts with both plugins.

Layout

plugin

A pom with the dependencies need and common classes for all plugins. In this case just the MenuEntry stuff

application

This contains the spring-boot application

plugin-*

This modules contain the implementation of the modules.