You need to check the documentation about Integration Services.
The full documentation about you can find here: https://my.backbase.com/docs/product-documentation/documentation//portal/5.6.2/develop_integrationservices.html
The documentation will help you to develop own service (I prefer use Camel Java DSL way), and you will get the url like:
http://localhost:7777/portalserver/services/rest/v1/myService
.
here the example of Java implementation of service:
public class MyCamelService extends RouteBuilder {
@Override
public void configure() throws Exception {
from("restlet:/v1/myService")
.setBody().constant("<html><body><b>Hello World!</b></body></html>")
.setHeader("Content-Type", constant("text/html"));
}
}