java 30 lines · 7 steps

Header-driven endpoints in a Spring controller

A REST controller reads path variables and request headers, then handles a missing-header error locally.

Explained by highlit

Spring Intermediate rest api request headers dependency injection exception handling multi-tenancy

1@RestController
2@RequestMapping("/api/reports")
3public class ReportController {
4 
  private final ReportService reportService;
6 
  public ReportController(ReportService reportService) {
      this.reportService = reportService;
  }
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  @GetMapping("/{id}")
  public ResponseEntity<ReportView> getReport(
          @PathVariable Long id,
          @RequestHeader("X-Tenant-Id") String tenantId,
          @RequestHeader(value = "X-Report-Format", defaultValue = "summary") String format) {
16 
      ReportView view = reportService.render(id, tenantId, format);
      return ResponseEntity.ok()
              .header("X-Report-Format", format)
              .body(view);
  }
22 
  @ExceptionHandler(MissingRequestHeaderException.class)
  public ResponseEntity<ApiError> handleMissingHeader(MissingRequestHeaderException ex) {
      ApiError error = new ApiError(
              HttpStatus.BAD_REQUEST.value(),
              "Missing required header: " + ex.getHeaderName());
      return ResponseEntity.badRequest().body(error);
  }
30}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Request headers can carry cross-cutting context like tenant identity without polluting the URL path.
2Header options with defaults keep some inputs optional while others stay mandatory.
3A controller-scoped @ExceptionHandler turns framework exceptions into clean, structured error responses.

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