81. Writing Groovy Scripts and Running Applications

Spring Cloud CLI has support for most of the Spring Cloud declarative features, such as the @Enable* class of annotations. For example, here is a fully functional Eureka server

app.groovy. 

@EnableEurekaServer
class Eureka {}

which you can run from the command line like this

$ spring run app.groovy

To include additional dependencies, often it suffices just to add the appropriate feature-enabling annotation, e.g. @EnableConfigServer, @EnableOAuth2Sso or @EnableEurekaClient. To manually include a dependency you can use a @Grab with the special "Spring Boot" short style artifact co-ordinates, i.e. with just the artifact ID (no need for group or version information), e.g. to set up a client app to listen on AMQP for management events from the Spring CLoud Bus:

app.groovy. 

@Grab('spring-cloud-starter-bus-amqp')
@RestController
class Service {
  @RequestMapping('/')
  def home() { [message: 'Hello'] }
}