springboot-plugin

Hawtio Spring Boot 3 with Plugin Example

This sample application demonstrates how to write and use a custom plugin with Spring Boot 3.

Key components

The key components of this sample are as follows:

File/Directory	Description
../sample-plugin/	The Hawtio v3 plugin project written in TypeScript. Since a Hawtio plugin is based on React and Webpack Module Federation, this project uses Yarn v3 and CRACO as the build tools. You can use any JS/TS tools for developing a Hawtio plugin so long as they can build a React and Webpack Module Federation application.
SampleSpringBootService.java	This is where the application registers the plugin to Hawtio. To register a plugin in Spring Boot, it should create the Spring Boot version of HawtioPlugin and provide it to Spring context. The three key parameters to pass to HawtioPlugin are url, scope, and module, which are required by Module Federation.

How to run

Run with:

mvn spring-boot:run

Hawtio is exposed at the Actuator management port configured using management.server.port in application.properties. Browse Hawtio via the following URL: http://localhost:10001/actuator/hawtio/

The actual application is running on port 10000 (server.port in application.properties).

Alternative configurations

Alternative management endpoint base paths

If your preference is to avoid running Hawtio under the /actuator path, you can set the management.endpoints.web.base-path property in application.properties:

management.server.port=10001
management.endpoints.web.base-path=/

Hawtio will then be available at http://localhost:10001/hawtio/index.html.

Alternative hawtio endpoint paths

You can also customize the endpoint path of the Hawtio actuator endpoint by setting the management.endpoints.web.path-mapping.hawtio property in application.properties:

management.server.port=10001
management.endpoints.web.base-path=/
management.endpoints.web.path-mapping.hawtio=hawtio/console

With the above configuration, Hawtio will be available at http://localhost:10001/hawtio/console/index.html.

Alternative ports & context paths

When management.server.port is not specified or is the same as server.port, Spring Boot will configure and start only one web server and will use only one context.

In this case, we can alter the context path with this configuration:

server.port=10000
server.servlet.context-path=/sample-app

Using the above configuration, the server will use port 10000 both for application and management endpoints and custom context path sample-app will be used for both.

• Application: http://localhost:10000/sample-app/
• Hawtio: http://localhost:10000/sample-app/actuator/hawtio

(/actuator prefix can be configured using management.endpoints.web.base-path property as described earlier.)

When management.server.port is specified and is different than server.port, Spring Boot will start two instances of web server and we can then configure separate context paths for application and for management endpoints.

For example:

server.port=10000
management.server.port=10001

server.servlet.context-path=/sample-app
management.server.base-path=/management

(management.server.base-path is a property that replaced management.server.servlet.context-path, which was deprecated in spring-projects/spring-boot@10f887a5ad696161787a60eacc5258c3f4f07263 and removed in spring-projects/spring-boot@dc5acb00191c2eac09907c39e4d890343bf9848d.)

Using the above configuration, the server will use port 10000 and the custom context path sample-app. The Actuator management endpoints and Hawtio will also run on port 10000 using the custom management context path management. The URLs for accessing the application and Hawtio are as follows:

• Application: http://localhost:10000/sample-app/
• Hawtio: http://localhost:10001/management/actuator/hawtio