Custom endpoints

Custom endpoints are methods inside a controller class that may look as follows.

@RestController
@RequestMapping("/api/todoItems")
public class CustomEndpointController {

    // ...
}

If you are using Kotlin, you should add the open modifier to the class declaration.

For a controller to be recognized as a container for custom endpoints, it needs to fulfill the following criteria:

• It must have a @RestController and a @RequestMapping annotation

Take note that the spring.data.rest.base-path you specified in application.properties will not be applied to the @RequestMapping unless you also add the annotation @BasePathAwareController.

You can then specify custom endpoints in such classes where parameters are annotated with @RequestParam, @PathVariable or @RequestBody.

@RequestMapping("createOrUpdate", method = [RequestMethod.POST])
open fun createOrUpdateContact(
        @RequestParam firstName: String,
        @RequestParam lastName: String
): ResponseEntity<EntityModel<User>> {
    // ...
}

FeGen will generate a method in the API client corresponding to the path or value in @RequestMapping if the backend method has a @RequestMapping (or @GetMapping, @PostMapping, etc.) annotation.

Custom endpoints must have a void return type or return entities. In the latter case, the entity class must be wrapped in an EntityModel (if a single entity should be returned) or in CollectionModel or PagedModel (if multiple entities should be returned). Those classes themselves must be wrapped in a ResponseEntity.

Custom endpoints can also return pojos. In this case, a pojo or a list of those must be wrapped in a ResponseEntity. They may also respond with primitive values in the same way. Returning String is however not supported, since they will not be converted to a JSON string. Instead, return a TextNode wrapped in a ReponseEntity.

To reliably use the returned values in the frontend, make sure you added the fegen-spring-util dependency to your Spring project.