Padding as a Dart RPC service

api.dart

library string_pad.api;

import 'dart:async';
import 'dart:io';

import 'package:rpc/rpc.dart';

class PaddingResponse {
  String result;
}

@ApiClass(
    name: 'pad',
    version: 'v1',
    description: 'Padding all the strings'
)
class Api {
  Api();

  @ApiMethod(method: 'GET', path: 'left/{width}')
  PaddingResponse left(int width, {String str, String ch}) {
    str ??= '';
    ch ??= ' ';

    return new PaddingResponse()
        ..result = str.padLeft(width, ch);
  }

  @ApiMethod(method: 'GET', path: 'right/{width}')
  PaddingResponse right(int width, {String str, String ch}) {
    str ??= '';
    ch ??= ' ';

    return new PaddingResponse()
        ..result = str.padRight(width, ch);
  }
}