Soul网关(8) - 数据同步之Http

话不多说，上来就干

上一篇了解通过websocket同步数据，这一篇我们来学习一下soul中通过http模式同步数据

配置

soul-admin和soul-bootstrap的yml配置

soul:
  sync:  //同步策略配置
    http:
        enabled: true

初始化

需要初始化http长轮询监听器

   /**
     * http long polling(default strategy).
     */
    @Configuration
    @ConditionalOnProperty(name = "soul.sync.http.enabled", havingValue = "true")
    @EnableConfigurationProperties(HttpSyncProperties.class)
    static class HttpLongPollingListener {

        @Bean
        @ConditionalOnMissingBean(HttpLongPollingDataChangedListener.class)
        public HttpLongPollingDataChangedListener httpLongPollingDataChangedListener(final HttpSyncProperties httpSyncProperties) {
            return new HttpLongPollingDataChangedListener(httpSyncProperties);
        }

    }

这个监听器同样继承了数据变更监听器顶级接口DataChangedListener，这个接口在上一篇提到过，是针对auth、plugin、selector、metadata、rule数据的监听接口

通过事件发布机制，发布事件

    private void publishEvent(final SelectorDO selectorDO, final List<SelectorConditionDTO> selectorConditionDTOs) {
        PluginDO pluginDO = pluginMapper.selectById(selectorDO.getPluginId());
        List<ConditionData> conditionDataList =
                selectorConditionDTOs.stream().map(ConditionTransfer.INSTANCE::mapToSelectorDTO).collect(Collectors.toList());
        // publish change event.
        // ConfigGroupEnum.SELECTOR 事件分组枚举
        // DataEventTypeEnum.UPDATE 事件类型
        eventPublisher.publishEvent(new DataChangedEvent(ConfigGroupEnum.SELECTOR, DataEventTypeEnum.UPDATE,
                Collections.singletonList(SelectorDO.transFrom(selectorDO, pluginDO.getName(), conditionDataList))));
    }

通过事件分组枚举值和事件类型枚举值，获取不同的监听器和监听事件

    public ConfigData<?> fetchConfig(final ConfigGroupEnum groupKey) {
        ConfigDataCache config = CACHE.get(groupKey.name());
        switch (groupKey) {
            case APP_AUTH:
                List<AppAuthData> appAuthList = GsonUtils.getGson().fromJson(config.getJson(), new TypeToken<List<AppAuthData>>() {
                }.getType());
                return new ConfigData<>(config.getMd5(), config.getLastModifyTime(), appAuthList);
            case PLUGIN:
                List<PluginData> pluginList = GsonUtils.getGson().fromJson(config.getJson(), new TypeToken<List<PluginData>>() {
                }.getType());
                return new ConfigData<>(config.getMd5(), config.getLastModifyTime(), pluginList);
            case RULE:
                List<RuleData> ruleList = GsonUtils.getGson().fromJson(config.getJson(), new TypeToken<List<RuleData>>() {
                }.getType());
                return new ConfigData<>(config.getMd5(), config.getLastModifyTime(), ruleList);
            case SELECTOR:
                List<SelectorData> selectorList = GsonUtils.getGson().fromJson(config.getJson(), new TypeToken<List<SelectorData>>() {
                }.getType());
                return new ConfigData<>(config.getMd5(), config.getLastModifyTime(), selectorList);
            case META_DATA:
                List<MetaData> metaList = GsonUtils.getGson().fromJson(config.getJson(), new TypeToken<List<MetaData>>() {
                }.getType());
                return new ConfigData<>(config.getMd5(), config.getLastModifyTime(), metaList);
            default:
                throw new IllegalStateException("Unexpected groupKey: " + groupKey);
        }
    }

通过DataChangedEventDispatcher调度者，匹配到对应的监听器

    public void onApplicationEvent(final DataChangedEvent event) {
        for (DataChangedListener listener : listeners) {
            switch (event.getGroupKey()) {
                case APP_AUTH:
                    listener.onAppAuthChanged((List<AppAuthData>) event.getSource(), event.getEventType());
                    break;
                case PLUGIN:
                    listener.onPluginChanged((List<PluginData>) event.getSource(), event.getEventType());
                    break;
                case RULE:
                    listener.onRuleChanged((List<RuleData>) event.getSource(), event.getEventType());
                    break;
                case SELECTOR:
                    listener.onSelectorChanged((List<SelectorData>) event.getSource(), event.getEventType());
                    break;
                case META_DATA:
                    listener.onMetaDataChanged((List<MetaData>) event.getSource(), event.getEventType());
                    break;
                default:
                    throw new IllegalStateException("Unexpected value: " + event.getGroupKey());
            }
        }
    }

http长轮询监听器HttpLongPollingDataChangedListener是通过继承抽象类abstractDataChangedListener来实现的，

    public void onRuleChanged(final List<RuleData> changed, final DataEventTypeEnum eventType) {
        if (CollectionUtils.isEmpty(changed)) {
            return;
        }
        //直接更新缓存
        this.updateRuleCache();
        // 通过执行器轮询
        this.afterRuleChanged(changed, eventType);
    }

执行器

    protected void afterRuleChanged(final List<RuleData> changed, final DataEventTypeEnum eventType) {
        scheduler.execute(new DataChangeTask(ConfigGroupEnum.RULE));
    }

DataChangeTask是HttpLongPollingDataChangedListener的内部类,实现了Runnable接口,重写run()方法

       public void run() {
         // clinets是阻塞队列
            for (Iterator<LongPollingClient> iter = clients.iterator(); iter.hasNext();) {
                LongPollingClient client = iter.next();
                iter.remove();
                // 发送轮询信息
                client.sendResponse(Collections.singletonList(groupKey));
                log.info("send response with the changed group,ip={}, group={}, changeTime={}", client.ip, groupKey, changeTime);
            }
        }