dubbo check=true源码分析

冷不防 2023-06-27 03:24 26阅读 0赞

1. 问题

> check=true到底检查的是什么？

2. debug查看

ReferenceConfig里面的createProxy方法

>     if (shouldCheck() && !invoker.isAvailable()) {
>         throw new IllegalStateException("Failed to check the status of the service " + interfaceName + ". No provider available for the service " + (group == null ? "" : group + "/") + interfaceName + (version == null ? "" : ":" + version) + " from the url " + invoker.getUrl() + " to the consumer " + NetUtils.getLocalHost() + " use dubbo version " + Version.getVersion());
>     }

判断是否需要check

>     protected boolean shouldCheck() {
>         Boolean shouldCheck = isCheck();
>         if (shouldCheck == null && getConsumer() != null) {
>             shouldCheck = getConsumer().isCheck();
>         }
>         if (shouldCheck == null) {
>             // default true
>             shouldCheck = true;
>         }
>         return shouldCheck;
>     }

>     // AbstractReferenceConfig配置中，check来自配置
>     public Boolean isCheck() {
>         return check;
>     }

关键代码：

invoker.isAvailable()

RegistryDirectory类

>     @Override
>     public boolean isAvailable() {
>         if (isDestroyed()) {
>             return false;
>         }
>         Map<String, Invoker<T>> localUrlInvokerMap = urlInvokerMap;
>         if (localUrlInvokerMap != null && localUrlInvokerMap.size() > 0) {
>             for (Invoker<T> invoker : new ArrayList<>(localUrlInvokerMap.values())) {
>                 if (invoker.isAvailable()) {
>                     return true;
>                 }
>             }
>         }
>         return false;
>     }

DubboInvoker

>     @Override
>     public boolean isAvailable() {
>         if (!super.isAvailable()) {
>             return false;
>         }
>         for (ExchangeClient client : clients) {
>             if (client.isConnected() && !client.hasAttribute(Constants.CHANNEL_ATTRIBUTE_READONLY_KEY)) {
>                 //cannot write == not Available ?
>                 return true;
>             }
>         }
>         return false;
>     }

>  // 连接是否已经建立
> 
>     @Override
>     public boolean isConnected() {
>         return channel.isConnected();
>     }