code: @RequestMapping(value = "changelog/diff", method = RequestMethod.GET)
      public ResponseEntity<String> diff(FileDiffChangeLogRequest request) {
          // Gets the change log
          SVNChangeLog changeLog = changeLogService.changeLog(request);
          // Gets the files
          SVNChangeLogFiles changeLogFiles = changeLogService.getChangeLogFiles(changeLog);
          // Diff export
          String diff = scmService.diff(
                  changeLogFiles.getList(),
                  request.getPatterns(),
                  changeLogFile -> changeLogService.getDiff(changeLog.getRepository(), changeLogFile)
          );
          // Content type
          HttpHeaders responseHeaders = new HttpHeaders();
          responseHeaders.set("Content-Type", "text/plain");
          // Body and headers
          return new ResponseEntity<>(diff, responseHeaders, HttpStatus.OK);
      }
docs: File diff change log