一、Dubbo 集成了spring提供自定义Xml的接口进行扩展，前面spring使用篇有demo看了就知道是怎么回事。
二、DubboNamespaceHandler 这个类就是Dubbo扩展xml的启动类，接下来我们重点分析
org.apache.dubbo.config.spring.schema.DubboNamespaceHandler
public class DubboNamespaceHandler extends NamespaceHandlerSupport {
static {
Version.checkDuplicate(DubboNamespaceHandler.class);
}
// 解析标签 这个没什么难度，看下官方文档就明白了
// 1、 大致思想是解析dubbo扩展xml的属性封装成beanDefinition
@Override
public void init() {
registerBeanDefinitionParser("application", new DubboBeanDefinitionParser(ApplicationConfig.class, true));
registerBeanDefinitionParser("module", new DubboBeanDefinitionParser(ModuleConfig.class, true));
registerBeanDefinitionParser("registry", new DubboBeanDefinitionParser(RegistryConfig.class, true));
registerBeanDefinitionParser("config-center", new DubboBeanDefinitionParser(ConfigCenterBean.class, true));
registerBeanDefinitionParser("metadata-report", new DubboBeanDefinitionParser(MetadataReportConfig.class, true));
registerBeanDefinitionParser("monitor", new DubboBeanDefinitionParser(MonitorConfig.class, true));
registerBeanDefinitionParser("provider", new DubboBeanDefinitionParser(ProviderConfig.class, true));
registerBeanDefinitionParser("consumer", new DubboBeanDefinitionParser(ConsumerConfig.class, true));
registerBeanDefinitionParser("protocol", new DubboBeanDefinitionParser(ProtocolConfig.class, true));
registerBeanDefinitionParser("service", new DubboBeanDefinitionParser(ServiceBean.class, true));
registerBeanDefinitionParser("reference", new DubboBeanDefinitionParser(ReferenceBean.class, false));
registerBeanDefinitionParser("annotation", new AnnotationBeanDefinitionParser());
}
}
- ApplicationConfig
- ModuleConfig
- RegistryConfig
- ConfigCenterBean
- MonitorConfig
- ProviderConfig
- ConsumerConfig
- ProtocolConfig
- ServiceBean
- ReferenceBean
分析SeviceBean源码分析
public void afterPropertiesSet() throws Exception {
// <service:provider provider:"id">
if (getProvider() == null) {
// 总结:
// 1、从spring容器获取到该类的配置项目
// 2、从spring容器中获取到协议相关的配置
// 3、找到直接load 容器 providerConfigs
// 4、如果没有找到设置一个空的对象放入里面
Map<String, ProviderConfig> providerConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ProviderConfig.class, false, false);
if (providerConfigMap != null && providerConfigMap.size() > 0) {
// 获取所有的协议配置ProtocolConfig
Map<String, ProtocolConfig> protocolConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ProtocolConfig.class, false, false);
if (CollectionUtils.isEmptyMap(protocolConfigMap)
&& providerConfigMap.size() > 1) { // backward compatibility
List<ProviderConfig> providerConfigs = new ArrayList<ProviderConfig>();
for (ProviderConfig config : providerConfigMap.values()) {
if (config.isDefault() != null && config.isDefault()) {
providerConfigs.add(config);
}
}
if (!providerConfigs.isEmpty()) {
setProviders(providerConfigs);
}
} else {
ProviderConfig providerConfig = null;
// 提供配置
for (ProviderConfig config : providerConfigMap.values()) {
if (config.isDefault() == null || config.isDefault()) {
if (providerConfig != null) {
// 重复提供配置
throw new IllegalStateException("Duplicate provider configs: " + providerConfig + " and " + config);
}
providerConfig = config;
}
}
// 没有提供proverderConfig
if (providerConfig != null) {
setProvider(providerConfig);
}
}
}
}
// 获取上下文配置
if (getApplication() == null
&& (getProvider() == null || getProvider().getApplication() == null)) {
Map<String, ApplicationConfig> applicationConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ApplicationConfig.class, false, false);
if (applicationConfigMap != null && applicationConfigMap.size() > 0) {
ApplicationConfig applicationConfig = null;
for (ApplicationConfig config : applicationConfigMap.values()) {
if (applicationConfig != null) {
throw new IllegalStateException("Duplicate application configs: " + applicationConfig + " and " + config);
}
applicationConfig = config;
}
if (applicationConfig != null) {
setApplication(applicationConfig);
}
}
}
if (getModule() == null
&& (getProvider() == null || getProvider().getModule() == null)) {
Map<String, ModuleConfig> moduleConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ModuleConfig.class, false, false);
if (moduleConfigMap != null && moduleConfigMap.size() > 0) {
ModuleConfig moduleConfig = null;
for (ModuleConfig config : moduleConfigMap.values()) {
if (config.isDefault() == null || config.isDefault()) {
if (moduleConfig != null) {
throw new IllegalStateException("Duplicate module configs: " + moduleConfig + " and " + config);
}
moduleConfig = config;
}
}
if (moduleConfig != null) {
setModule(moduleConfig);
}
}
}
if (StringUtils.isEmpty(getRegistryIds())) {
if (getApplication() != null && StringUtils.isNotEmpty(getApplication().getRegistryIds())) {
setRegistryIds(getApplication().getRegistryIds());
}
if (getProvider() != null && StringUtils.isNotEmpty(getProvider().getRegistryIds())) {
setRegistryIds(getProvider().getRegistryIds());
}
}
if ((CollectionUtils.isEmpty(getRegistries()))
&& (getProvider() == null || CollectionUtils.isEmpty(getProvider().getRegistries()))
&& (getApplication() == null || CollectionUtils.isEmpty(getApplication().getRegistries()))) {
Map<String, RegistryConfig> registryConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, RegistryConfig.class, false, false);
if (CollectionUtils.isNotEmptyMap(registryConfigMap)) {
List<RegistryConfig> registryConfigs = new ArrayList<>();
if (StringUtils.isNotEmpty(registryIds)) {
Arrays.stream(Constants.COMMA_SPLIT_PATTERN.split(registryIds)).forEach(id -> {
if (registryConfigMap.containsKey(id)) {
registryConfigs.add(registryConfigMap.get(id));
}
});
}
if (registryConfigs.isEmpty()) {
for (RegistryConfig config : registryConfigMap.values()) {
if (StringUtils.isEmpty(registryIds)) {
registryConfigs.add(config);
}
}
}
if (!registryConfigs.isEmpty()) {
super.setRegistries(registryConfigs);
}
}
}
if (getMetadataReportConfig() == null) {
Map<String, MetadataReportConfig> metadataReportConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, MetadataReportConfig.class, false, false);
if (metadataReportConfigMap != null && metadataReportConfigMap.size() == 1) {
super.setMetadataReportConfig(metadataReportConfigMap.values().iterator().next());
} else if (metadataReportConfigMap != null && metadataReportConfigMap.size() > 1) {
throw new IllegalStateException("Multiple MetadataReport configs: " + metadataReportConfigMap);
}
}
if (getConfigCenter() == null) {
Map<String, ConfigCenterConfig> configenterMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ConfigCenterConfig.class, false, false);
if (configenterMap != null && configenterMap.size() == 1) {
super.setConfigCenter(configenterMap.values().iterator().next());
} else if (configenterMap != null && configenterMap.size() > 1) {
throw new IllegalStateException("Multiple ConfigCenter found:" + configenterMap);
}
}
if (getMonitor() == null
&& (getProvider() == null || getProvider().getMonitor() == null)
&& (getApplication() == null || getApplication().getMonitor() == null)) {
Map<String, MonitorConfig> monitorConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, MonitorConfig.class, false, false);
if (monitorConfigMap != null && monitorConfigMap.size() > 0) {
MonitorConfig monitorConfig = null;
for (MonitorConfig config : monitorConfigMap.values()) {
if (config.isDefault() == null || config.isDefault()) {
if (monitorConfig != null) {
throw new IllegalStateException("Duplicate monitor configs: " + monitorConfig + " and " + config);
}
monitorConfig = config;
}
}
if (monitorConfig != null) {
setMonitor(monitorConfig);
}
}
}
if (StringUtils.isEmpty(getProtocolIds())) {
if (getProvider() != null && StringUtils.isNotEmpty(getProvider().getProtocolIds())) {
setProtocolIds(getProvider().getProtocolIds());
}
}
if (CollectionUtils.isEmpty(getProtocols())
&& (getProvider() == null || CollectionUtils.isEmpty(getProvider().getProtocols()))) {
Map<String, ProtocolConfig> protocolConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ProtocolConfig.class, false, false);
if (protocolConfigMap != null && protocolConfigMap.size() > 0) {
List<ProtocolConfig> protocolConfigs = new ArrayList<ProtocolConfig>();
if (StringUtils.isNotEmpty(getProtocolIds())) {
Arrays.stream(Constants.COMMA_SPLIT_PATTERN.split(getProtocolIds()))
.forEach(id -> {
if (protocolConfigMap.containsKey(id)) {
protocolConfigs.add(protocolConfigMap.get(id));
}
});
}
if (protocolConfigs.isEmpty()) {
for (ProtocolConfig config : protocolConfigMap.values()) {
if (StringUtils.isEmpty(protocolIds)) {
protocolConfigs.add(config);
}
}
}
if (!protocolConfigs.isEmpty()) {
super.setProtocols(protocolConfigs);
}
}
}
if (StringUtils.isEmpty(getPath())) {
if (StringUtils.isNotEmpty(beanName)
&& StringUtils.isNotEmpty(getInterface())
&& beanName.startsWith(getInterface())) {
setPath(beanName);
}
}
if (!supportedApplicationListener) {
export();
}
}
总个这段代码是如何从spring容器中装载bean到内存中来，方面计算。
获取到配置，然后将其注册到zookeeper上面，下面分析如果提供服务，同时把元数据信息注册到zookeeper，如果进行服务续约。等等
org.apache.dubbo.config.spring.ServiceBean#export
if (!supportedApplicationListener) {
export();
}
org.apache.dubbo.config.ServiceConfig#export
public synchronized void export() {
checkAndUpdateSubConfigs();
if (provider != null) {
if (export == null) {
export = provider.getExport();
}
if (delay == null) {
delay = provider.getDelay();
}
}
if (export != null && !export) { //@1
return;
}
// 延时导出
if (delay != null && delay > 0) {
// 延时导出
delayExportExecutor.schedule(this::doExport, delay, TimeUnit.MILLISECONDS);
} else {
// 直接导出
doExport();
}
}
- 是否暴露服务
- 延时暴露
org.apache.dubbo.config.ServiceConfig#doExport
protected synchronized void doExport() {
if (unexported) {
throw new IllegalStateException("The service " + interfaceClass.getName() + " has already unexported!");
}
if (exported) {
return;
}
exported = true;
if (StringUtils.isEmpty(path)) {
path = interfaceName;
}
String uniqueServiceName = getUniqueServiceName();
ProviderModel providerModel = new ProviderModel(uniqueServiceName, ref, interfaceClass);
ApplicationModel.initProviderModel(uniqueServiceName, providerModel);
// 拼接url
doExportUrls();
}
org.apache.dubbo.config.ServiceConfig#doExportUrls
private void doExportUrls() {
List<URL> registryURLs = loadRegistries(true);
for (ProtocolConfig protocolConfig : protocols) {
doExportUrlsFor1Protocol(protocolConfig, registryURLs);
}
}
org.apache.dubbo.config.ServiceConfig#doExportUrlsFor1Protocol
private void doExportUrlsFor1Protocol(ProtocolConfig protocolConfig, List<URL> registryURLs) {
String name = protocolConfig.getName();
if (StringUtils.isEmpty(name)) {
// 默认使用dubbo协议
name = Constants.DUBBO;
}
// 定义一个容器用于存放参数
Map<String, String> map = new HashMap<String, String>();
map.put(Constants.SIDE_KEY, Constants.PROVIDER_SIDE);
appendRuntimeParameters(map);
appendParameters(map, application);
appendParameters(map, module);
appendParameters(map, provider, Constants.DEFAULT_KEY);
appendParameters(map, protocolConfig);
appendParameters(map, this);
// 第一方法
if (CollectionUtils.isNotEmpty(methods)) {
for (MethodConfig method : methods) {
appendParameters(map, method, method.getName());
String retryKey = method.getName() + ".retry";
if (map.containsKey(retryKey)) {
String retryValue = map.remove(retryKey);
if ("false".equals(retryValue)) {
map.put(method.getName() + ".retries", "0");
}
}
List<ArgumentConfig> arguments = method.getArguments();
if (CollectionUtils.isNotEmpty(arguments)) {
for (ArgumentConfig argument : arguments) {
// convert argument type
if (argument.getType() != null && argument.getType().length() > 0) {
Method[] methods = interfaceClass.getMethods();
// visit all methods
if (methods != null && methods.length > 0) {
for (int i = 0; i < methods.length; i++) {
String methodName = methods[i].getName();
// target the method, and get its signature
if (methodName.equals(method.getName())) {
Class<?>[] argtypes = methods[i].getParameterTypes();
// one callback in the method
if (argument.getIndex() != -1) {
if (argtypes[argument.getIndex()].getName().equals(argument.getType())) {
appendParameters(map, argument, method.getName() + "." + argument.getIndex());
} else {
throw new IllegalArgumentException("Argument config error : the index attribute and type attribute not match :index :" + argument.getIndex() + ", type:" + argument.getType());
}
} else {
// multiple callbacks in the method
for (int j = 0; j < argtypes.length; j++) {
Class<?> argclazz = argtypes[j];
if (argclazz.getName().equals(argument.getType())) {
appendParameters(map, argument, method.getName() + "." + j);
if (argument.getIndex() != -1 && argument.getIndex() != j) {
throw new IllegalArgumentException("Argument config error : the index attribute and type attribute not match :index :" + argument.getIndex() + ", type:" + argument.getType());
}
}
}
}
}
}
}
} else if (argument.getIndex() != -1) {
appendParameters(map, argument, method.getName() + "." + argument.getIndex());
} else {
throw new IllegalArgumentException("Argument config must set index or type attribute.eg: <dubbo:argument index='0' .../> or <dubbo:argument type=xxx .../>");
}
}
}
} // end of methods for
}
if (ProtocolUtils.isGeneric(generic)) {
map.put(Constants.GENERIC_KEY, generic);
map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
} else {
String revision = Version.getVersion(interfaceClass, version);
if (revision != null && revision.length() > 0) {
map.put("revision", revision);
}
String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames();
if (methods.length == 0) {
logger.warn("No method found in service interface " + interfaceClass.getName());
map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
} else {
map.put(Constants.METHODS_KEY, StringUtils.join(new HashSet<String>(Arrays.asList(methods)), ","));
}
}
if (!ConfigUtils.isEmpty(token)) {
if (ConfigUtils.isDefault(token)) {
map.put(Constants.TOKEN_KEY, UUID.randomUUID().toString());
} else {
map.put(Constants.TOKEN_KEY, token);
}
}
// export service
String contextPath = protocolConfig.getContextpath();
if (StringUtils.isEmpty(contextPath) && provider != null) {
contextPath = provider.getContextpath();
}
String host = this.findConfigedHosts(protocolConfig, registryURLs, map);
Integer port = this.findConfigedPorts(protocolConfig, name, map);
URL url = new URL(name, host, port, (StringUtils.isEmpty(contextPath) ? "" : contextPath + "/") + path, map);
if (ExtensionLoader.getExtensionLoader(ConfiguratorFactory.class)
.hasExtension(url.getProtocol())) {
url = ExtensionLoader.getExtensionLoader(ConfiguratorFactory.class)
.getExtension(url.getProtocol()).getConfigurator(url).configure(url);
}
String scope = url.getParameter(Constants.SCOPE_KEY);
// don't export when none is configured
if (!Constants.SCOPE_NONE.equalsIgnoreCase(scope)) {
// export to local if the config is not remote (export to remote only when config is remote)
if (!Constants.SCOPE_REMOTE.equalsIgnoreCase(scope)) {
exportLocal(url);
}
// export to remote if the config is not local (export to local only when config is local)
if (!Constants.SCOPE_LOCAL.equalsIgnoreCase(scope)) {
if (logger.isInfoEnabled()) {
logger.info("Export dubbo service " + interfaceClass.getName() + " to url " + url);
}
if (CollectionUtils.isNotEmpty(registryURLs)) {
for (URL registryURL : registryURLs) {
url = url.addParameterIfAbsent(Constants.DYNAMIC_KEY, registryURL.getParameter(Constants.DYNAMIC_KEY));
URL monitorUrl = loadMonitor(registryURL);
if (monitorUrl != null) {
url = url.addParameterAndEncoded(Constants.MONITOR_KEY, monitorUrl.toFullString());
}
if (logger.isInfoEnabled()) {
logger.info("Register dubbo service " + interfaceClass.getName() + " url " + url + " to registry " + registryURL);
}
// For providers, this is used to enable custom proxy to generate invoker
String proxy = url.getParameter(Constants.PROXY_KEY);
if (StringUtils.isNotEmpty(proxy)) {
registryURL = registryURL.addParameter(Constants.PROXY_KEY, proxy);
}
Invoker<?> invoker = proxyFactory.getInvoker(ref, (Class) interfaceClass, registryURL.addParameterAndEncoded(Constants.EXPORT_KEY, url.toFullString()));
DelegateProviderMetaDataInvoker wrapperInvoker = new DelegateProviderMetaDataInvoker(invoker, this);
Exporter<?> exporter = protocol.export(wrapperInvoker);
exporters.add(exporter);
}
} else {
Invoker<?> invoker = proxyFactory.getInvoker(ref, (Class) interfaceClass, url);
DelegateProviderMetaDataInvoker wrapperInvoker = new DelegateProviderMetaDataInvoker(invoker, this);
Exporter<?> exporter = protocol.export(wrapperInvoker);
exporters.add(exporter);
}
/**
* @since 2.7.0
* ServiceData Store
*/
MetadataReportService metadataReportService = null;
if ((metadataReportService = getMetadataReportService()) != null) {
metadataReportService.publishProvider(url);
}
}
}
this.urls.add(url);
}
什么是本地存根，实现全部的provide端。有时候，Provider想让Customer执行部门逻辑，如果ThreadLocal缓存，提前验证参数，调用失败伪造容错数据
