https://github.com/apache/dubbo/blob/532ce72f8377abf8ff659430b86e0919c9aff562/dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ServiceConfig.java#L240-L248 

What ever user use `instance` service discovery or `interface` service discovery, we also publish service name mapping info. 
But service name mapping need metadata report dependency, so if some one just use `interface` service discovery, the user still need need metadata report dependency.

Here we add a judgement, check current service config use `instance` service discovery or not, to judge publish service name mapping or not.

exportedURLs.forEach(url -> {
            ServiceNameMapping serviceNameMapping = ServiceNameMapping.getDefaultExtension();
            serviceNameMapping.map(url);
        });
        onExported();
    }
    private void checkAndUpdateSubConfigs() {
        
        completeCompoundConfigs();
        checkProtocol();
        
        List<ConfigInitializer> configInitializers = ExtensionLoader.getExtensionLoader(ConfigInitializer.class)
                .getActivateExtension(URL.valueOf("configInitializer://"), (String[]) null);
        configInitializers.forEach(e -> e.initServiceConfig(this));
        
        if (!isOnlyInJvm()) {
            checkRegistry();
        }
        if (StringUtils.isEmpty(interfaceName)) {
            throw new IllegalStateException("<dubbo:service interface=\"\" /> interface not allow null!");
        }
        if (ref instanceof GenericService) {
            interfaceClass = GenericService.class;
            if (StringUtils.isEmpty(generic)) {
                generic = Boolean.TRUE.toString();
            }
        } else {
            try {
                interfaceClass = Class.forName(interfaceName, true, Thread.currentThread()
                        .getContextClassLoader());