基于命令行模式设计退款请求处理

前言

这篇文章的业务背景是基于我的另一篇文章:

对接苹果支付退款退单接口-CSDN博客

然后就是说设计模式是很开放的东西,可能我觉得合适,你可能觉得不合适,这里只是做下讨论,没有一定要各位同意的意思....

代码逻辑

先把每个类的代码放上来一下,首先是接口

涉及java类

AppNotifyCommand(这个没啥好说的)

public interface AppNotifyCommand<T extends AppStoreNotifyDto> {

    //命令定义,可以参考官网
    //https://developer.apple.com/documentation/appstoreservernotifications/notification_type
    String REFUND_COMMAND_NAME = "REFUND";



    String NOT_FOUND_COMMAND_NAME = "NOT_FOUND";

    /**
     *  获取命令名称
     * @return
     */
    String getCommandName();

    /**
     * 执行命令
     * @param T
     */
    String execute(T T);
}

AbstractAppNotifyCommand(抽象类,给子类继承的,还是比较有意义的)

@Slf4j
public abstract class AbstractAppNotifyCommand<T extends AppStoreNotifyDto> implements AppNotifyCommand<T>{
    @Override
    public String getCommandName() {
        String commandName = doGetCommandName();
        if(StringUtil.isBlank(commandName)) {
            throw new IllegalArgumentException("commandName为空");
        }
        return commandName;
    }

    @Override
    public String execute(T T) {
        try {
            return doExecute(T);
        } catch (Exception e) {
            log.error("执行具体命令时发生异常", e);
            throw new AppException("执行具体命令时发生异常", e);
        }
    }

    protected abstract String doGetCommandName();

    protected abstract String doExecute(T T) throws Exception;

}

AppRefundCommand(退款处理类)

@Service
public class AppRefundCommand extends AbstractAppNotifyCommand<AppStoreNotifyDto> {

    @Override
    protected String doGetCommandName() {
        return REFUND_COMMAND_NAME;
    }

    @Override
    protected String doExecute(AppStoreNotifyDto appStoreNotifyDto) throws Exception{

//        //获取解密数据
//        AppStoreDecodedPayloadDto appStoreDecodedPayloadDto = parseTransactionInfo(appStoreNotifyDto);
//
//        //退款逻辑处理.....


        return "执行完成了";
    }
}

AppNotFoundCommand(找不到对应的处理命令时也写了一个处理类)

@Slf4j
@Service
public class AppNotFoundCommand extends AbstractAppNotifyCommand<AppStoreNotifyDto> {
    @Override
    protected String doGetCommandName() {
        return NOT_FOUND_COMMAND_NAME;
    }

    @Override
    protected String doExecute(AppStoreNotifyDto appStoreNotifyDto) throws Exception {
        log.info("目前{}的命令没有进行处理,返回空字符串", appStoreNotifyDto.getNotificationType());
        return "";
    }
}

上面的几个类都是基础类,没啥好说的,主要是下面这个类,维护了对外的接口,如下

@Service
@Slf4j
public class AppCommandComposite {


    @Resource
    private List<AppNotifyCommand<AppStoreNotifyDto>> appNotifyCommandList;

    private Map<String, AppNotifyCommand<AppStoreNotifyDto>> appNotifyCommandMap;

    @PostConstruct
    public void init() {

        appNotifyCommandMap = new ConcurrentHashMap<>();

        //循环放置数据
        for (AppNotifyCommand<AppStoreNotifyDto> appNotifyCommand : appNotifyCommandList) {
            appNotifyCommandMap.put(appNotifyCommand.getCommandName(), appNotifyCommand);
        }
    }

    /**
     * 执行命令
     * @param appStoreNotifyPayLoadDto
     * @return
     */
    public String handleCommand(AppStoreNotifyPayLoadDto appStoreNotifyPayLoadDto) {
        try {

            //解密基础数据
            AppStoreNotifyDto appStoreNotifyDto = AppStoreReturnUtil.verifyAndGet(appStoreNotifyPayLoadDto.getSignedPayload());

            log.info("开始执行苹果的{}通知命令", appStoreNotifyDto.getNotificationType());

            //获取安全的执行器执行
            AppNotifyCommand<AppStoreNotifyDto> appNotifyCommand = appNotifyCommandMap.get(appStoreNotifyDto.getNotificationType());

            String result = safeAppNotifyCommand(appNotifyCommand).execute(appStoreNotifyDto);

            log.info("执行苹果的{}通知命令完成,返回的数据为{}", appStoreNotifyDto.getNotificationType(), result);

            return result;
        } catch (Exception e) {
            log.error("解析苹果加密数据失败", e);
            throw new AppException("解析苹果加密数据失败");
        }
    }

    //获取安全的执行器执行
    private AppNotifyCommand<AppStoreNotifyDto> safeAppNotifyCommand(AppNotifyCommand<AppStoreNotifyDto> appNotifyCommand) {

        if(appNotifyCommand == null) {
            return appNotifyCommandMap.get(AppNotifyCommand.NOT_FOUND_COMMAND_NAME);
        }

        return appNotifyCommand;
    }
}