Hands-On Microservices with Kotlin

From a request into an object

When we define our POST method to create customers, we define it in the following way:

@PostMapping(value = "/customer/")fun createCustomer(@RequestBody customer: Customer): ResponseEntity<Unit?> {  customerService.createCustomer(customer)  return ResponseEntity(null, HttpStatus.CREATED)}

Then, when a request is sent, for example as this cURL request:

curl -X POST \ http://localhost:8080/customer/ \ -H 'content-type: application/json' \ -d '{ "id": 4, "name": "New Customer"}'

Spring will get the body of the request and use the ObjectMapper to construct a JVM object of the specified class. The object mapper using reflection will find all the public attributes or setter methods for each property in the JSON object, ...