How to Build a RESTful API in Spring Boot 3: Best Practices & Validation

package com.programmingwala.demo;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import jakarta.validation.Valid;
import jakarta.validation.constraints.NotBlank;
import jakarta.validation.constraints.Pattern;

@RestController
@RequestMapping("/api/v1/inquiries")
public class InquiryController {

    public record InquiryDTO(
        @NotBlank(message = "Name cannot be empty") String name,
        @Pattern(regexp = "^\\d{10}$", message = "Phone must be 10 digits") String phone
    ) {}

    @PostMapping
    public ResponseEntity<String> submitInquiry(@Valid @RequestBody InquiryDTO dto) {
        // Service processing logic here...
        return ResponseEntity.status(HttpStatus.CREATED).body("Inquiry logged for: " + dto.name());
    }
}