dubbo源码——服务提供者的服务暴露过程(二)
原创
上篇博客讲到了doExportUrls()方法
#1顾名思义加载注册中心。（后面详细讲解#2获取并遍历所有协议，将服务根据不同协议暴露，并注册到每个注册中心上。
//ServiceConfig.java
//serviceConfig->doExportUrls()
@SuppressWarnings({"unchecked", "rawtypes"})
private void doExportUrls() {
List<URL> registryURLs = loadRegistries(true); #1
for (ProtocolConfig protocolConfig : protocols) { #2
doExportUrlsFor1Protocol(protocolConfig, registryURLs);
}
}#1检查registry，如果registries为空，则从环境中加载registry参数。#2如果registry标签的address属性为空，则默认为0.0.0.0#3从环境加载address,参数配置-Ddubbo.registry.address=127.0.0.1:2181，此优先级最高。#4将application，config填充到map#5将path设置为RegistryService类名。example:registry://127.0.0.1:2181/com.alibaba.dubbo.registry.RegistryService/xxxxxxx#6dubbo版本号、时间戳、pid，protocol#7
##1将address进行分割，和属性填充例如在一个标签中中配置了多个地址,example:<dubbo:registry
address="dubbo://127.0.0.1:2181;zookeeper://127.0.0.2:2181"/>，则会被分割为dubbo://127.0.0.1:2181 , zookeeper://127.0.0.12:2181来处理。
##2对url的参数进行一些填充，如protocol、username、password、port、host，path，最终生成的url：example: registry://127.0.0.1:2181/com.alibaba.dubbo.registry.RegistryService?application=demo2-service&dubbo=2.6.1&pid=1773×tamp=1528679207767
#8设置url参数，example: registry=zookeeper#9设置协议为registry#10我们在调用loadRegistries()时传入的参数为true，代表为服务提供者，那么register不应该为false，如果传入false，那说明为消费者，则subscribe不应该为false。
最终的url形式为example: registry://127.0.0.1:2181/com.alibaba.dubbo.registry.RegistryService?application=demo2-service&dubbo=2.6.1&pid=1922®istry=zookeeper×tamp=1528679861114
public static List<URL> parseURLs(String address, Map<String, String> defaults) {
if (address == null || address.length() == 0) {
return null;
}
String[] addresses = Constants.REGISTRY_SPLIT_PATTERN.split(address); ##1
if (addresses == null || addresses.length == 0) {
return null; //here won't be empty
}
List<URL> registries = new ArrayList<URL>();
for (String addr : addresses) {
registries.add(parseURL(addr, defaults)); ##2
}
return registries;
}public static URL parseURL(String address, Map<String, String> defaults) {
if (address == null || address.length() == 0) {
return null;
}
String url;
if (address.indexOf("://") >= 0) {
url = address;
} else {
String[] addresses = Constants.COMMA_SPLIT_PATTERN.split(address);
url = addresses[0];
if (addresses.length > 1) {
StringBuilder backup = new StringBuilder();
for (int i = 1; i < addresses.length; i++) {
if (i > 1) {
backup.append(",");
}
backup.append(addresses[i]);
}
url += "?" + Constants.BACKUP_KEY + "=" + backup.toString();
}
}
String defaultProtocol = defaults == null ? null : defaults.get("protocol");
if (defaultProtocol == null || defaultProtocol.length() == 0) {
defaultProtocol = "dubbo";
}
String defaultUsername = defaults == null ? null : defaults.get("username");
String defaultPassword = defaults == null ? null : defaults.get("password");
int defaultPort = StringUtils.parseInteger(defaults == null ? null : defaults.get("port"));
String defaultPath = defaults == null ? null : defaults.get("path");
Map<String, String> defaultParameters = defaults == null ? null : new HashMap<String, String>(defaults);
if (defaultParameters != null) {
defaultParameters.remove("protocol");
defaultParameters.remove("username");
defaultParameters.remove("password");
defaultParameters.remove("host");
defaultParameters.remove("port");
defaultParameters.remove("path");
}
URL u = URL.valueOf(url);
boolean changed = false;
String protocol = u.getProtocol();
String username = u.getUsername();
String password = u.getPassword();
String host = u.getHost();
int port = u.getPort();
String path = u.getPath();
Map<String, String> parameters = new HashMap<String, String>(u.getParameters());
if ((protocol == null || protocol.length() == 0) && defaultProtocol != null && defaultProtocol.length() > 0) {
changed = true;
protocol = defaultProtocol;
}
if ((username == null || username.length() == 0) && defaultUsername != null && defaultUsername.length() > 0) {
changed = true;
username = defaultUsername;
}
if ((password == null || password.length() == 0) && defaultPassword != null && defaultPassword.length() > 0) {
changed = true;
password = defaultPassword;
}
/*if (u.isAnyHost() || u.isLocalHost()) {
changed = true;
host = NetUtils.getLocalHost();
}*/
if (port <= 0) {
if (defaultPort > 0) {
changed = true;
port = defaultPort;
} else {
changed = true;
port = 9090;
}
}
if (path == null || path.length() == 0) {
if (defaultPath != null && defaultPath.length() > 0) {
changed = true;
path = defaultPath;
}
}
if (defaultParameters != null && defaultParameters.size() > 0) {
for (Map.Entry<String, String> entry : defaultParameters.entrySet()) {
String key = entry.getKey();
String defaultValue = entry.getValue();
if (defaultValue != null && defaultValue.length() > 0) {
String value = parameters.get(key);
if (value == null || value.length() == 0) {
changed = true;
parameters.put(key, defaultValue);
}
}
}
}
if (changed) {
u = new URL(protocol, username, password, host, port, path, parameters);
}
return u;
}//AbstractInterfaceConfig.java
//AbstractInterfaceConfig.loadRegistries()
protected List<URL> loadRegistries(boolean provider) {
checkRegistry(); #1
List<URL> registryList = new ArrayList<URL>();
if (registries != null && !registries.isEmpty()) {
for (RegistryConfig config : registries) {
String address = config.getAddress();
if (address == null || address.length() == 0) { #2
address = Constants.ANYHOST_VALUE;
}
String sysaddress = System.getProperty("dubbo.registry.address"); #3
if (sysaddress != null && sysaddress.length() > 0) {
address = sysaddress;
}
if (address != null && address.length() > 0
&& !RegistryConfig.NO_AVAILABLE.equalsIgnoreCase(address)) {
Map<String, String> map = new HashMap<String, String>();
appendParameters(map, application); #4
appendParameters(map, config);
map.put("path", RegistryService.class.getName()); #5
map.put("dubbo", Version.getVersion()); #6
map.put(Constants.TIMESTAMP_KEY, String.valueOf(System.currentTimeMillis()));
if (ConfigUtils.getPid() > 0) {
map.put(Constants.PID_KEY, String.valueOf(ConfigUtils.getPid()));
}
if (!map.containsKey("protocol")) {
if (ExtensionLoader.getExtensionLoader(RegistryFactory.class).hasExtension("remote")) {
map.put("protocol", "remote");
} else {
map.put("protocol", "dubbo");
}
}
List<URL> urls = UrlUtils.parseURLs(address, map); #7
for (URL url : urls) {
url = url.addParameter(Constants.REGISTRY_KEY, url.getProtocol()); #8
url = url.setProtocol(Constants.REGISTRY_PROTOCOL); #9
if ((provider && url.getParameter(Constants.REGISTER_KEY, true)) #10
|| (!provider && url.getParameter(Constants.SUBSCRIBE_KEY, true))) {
registryList.add(url);
}
}
}
}
}
return registryList;
}ok，既然注册中心URL构造好了，那么就该遍历每个协议，进行服务暴露和注册了！doExportUrlsFor1Protocol()
emmm，dubbo的方法命名和Spring的好像啊，do....就是方法也太长了吧。。
#1协议name，默认为dubbo。支持的协议还有rmi、hessian、http、webservice、thrift、redis#2设置side，dubbo，timestamp，pid，ApplicationConfig，ModuleConfig，ProviderCofnig，ProtocolConfig，ServiceConfig等参数#3如果在<dubbo:service/>标签中配置的子标签属性放入map。#4如果generic为true，那么将generic=true,method=*作为参数#5否则为普通接口，将当前服务的版本reversion=xxxx作为参数。#6获取接口中的方法名，用,分割for example: methods=test1,test2;如果不存在方法则使用通配符*。#7如果配置文件配置token为true或者default，则使用UUID作为token，否则将自定义。#8获取host
①从系统参数中中获取host example: -DDUBBO_IP_TO_BIND=192.168.1.1
String hostToBind = getValueFromConfig(protocolConfig, Constants.DUBBO_IP_TO_BIND);
②从配置文件中获取host example <dubbo:protocol host="192.168.1.1"/>
hostToBind = provider.getHost()
③从本机中获取host
hostToBind = InetAddress.getLocalHost().getHostAddress();
④获取注册中心的host
hostToBind = socket.getLocalAddress().getHostAddress();
⑤遍历本地网卡，返回第一个合理的IP
hostToBind = getLocalHost();
host有效性验证：
public static boolean isInvalidLocalHost(String host) {
return host == null
|| host.length() == 0
|| host.equalsIgnoreCase("localhost")
|| host.equals("0.0.0.0")
|| (LOCAL_IP_PATTERN.matcher(host).matches());
}#9 获取port
①从系统运行参数中获取 for example: -DDUBBO_PORT_TO_BIND=28080
String port = getValueFromConfig(protocolConfig, Constants.DUBBO_PORT_TO_BIND);
②从配置文件中获取 for example: <dubbo:protocol port="28080"/>
portToBind = protocolConfig.getPort();
③从provider配置中获取端口
portToBind = provider.getPort();
④获取协议默认端口
final int defaultPort = ExtensionLoader.getExtensionLoader(Protocol.class).getExtension(name).getDefaultPort();
⑤获取随机端口
portToBind = getRandomPort(name);
#10根据以上参数构造出协议对应的URL。#11如果配置了scope为none，则不暴露服务。#12如果scope配置为local，(默认为local),则在本地进行暴露，而不向注册中心进行注册服务。#13如果scope配置为remote，则先在本地进行暴露，然后向注册中心注册服务。
private void doExportUrlsFor1Protocol(ProtocolConfig protocolConfig, List<URL> registryURLs) {
String name = protocolConfig.getName(); #1
if (name == null || name.length() == 0) {
name = "dubbo";
}
Map<String, String> map = new HashMap<String, String>();
map.put(Constants.SIDE_KEY, Constants.PROVIDER_SIDE); #2
map.put(Constants.DUBBO_VERSION_KEY, Version.getVersion());
map.put(Constants.TIMESTAMP_KEY, String.valueOf(System.currentTimeMillis()));
if (ConfigUtils.getPid() > 0) {
map.put(Constants.PID_KEY, String.valueOf(ConfigUtils.getPid()));
}
appendParameters(map, application);
appendParameters(map, module);
appendParameters(map, provider, Constants.DEFAULT_KEY);
appendParameters(map, protocolConfig);
appendParameters(map, this);
if (methods != null && !methods.isEmpty()) { #3
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 (arguments != null && !arguments.isEmpty()) {
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)) { #4
map.put("generic", generic);
map.put("methods", Constants.ANY_VALUE);
} else { #5
String revision = Version.getVersion(interfaceClass, version);
if (revision != null && revision.length() > 0) {
map.put("revision", revision);
}
String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames(); #6
if (methods.length == 0) {
logger.warn("NO method found in service interface " + interfaceClass.getName());
map.put("methods", Constants.ANY_VALUE);
} else {
map.put("methods", StringUtils.join(new HashSet<String>(Arrays.asList(methods)), ","));
}
}
if (!ConfigUtils.isEmpty(token)) { #7
if (ConfigUtils.isDefault(token)) {
map.put("token", UUID.randomUUID().toString());
} else {
map.put("token", token);
}
}
if ("injvm".equals(protocolConfig.getName())) {
protocolConfig.setRegister(false);
map.put("notify", "false");
}
// export service
String contextPath = protocolConfig.getContextpath();
if ((contextPath == null || contextPath.length() == 0) && provider != null) {
contextPath = provider.getContextpath();
}
String host = this.findConfigedHosts(protocolConfig, registryURLs, map); #8
Integer port = this.findConfigedPorts(protocolConfig, name, map); #9
URL url = new URL(name, host, port, (contextPath == null || contextPath.length() == 0 ? "" : contextPath + "/") + path, map);
#10
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.toString().equalsIgnoreCase(scope)) { #11
// export to local if the config is not remote (export to remote only when config is remote)
if (!Constants.SCOPE_REMOTE.toString().equalsIgnoreCase(scope)) { #12
exportLocal(url);
}
// export to remote if the config is not local (export to local only when config is local)
if (!Constants.SCOPE_LOCAL.toString().equalsIgnoreCase(scope)) { #13
if (logger.isInfoEnabled()) {
logger.info("Export dubbo service " + interfaceClass.getName() + " to url " + url);
}
if (registryURLs != null && !registryURLs.isEmpty()) {
for (URL registryURL : registryURLs) {
url = url.addParameterIfAbsent("dynamic", registryURL.getParameter("dynamic"));
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);
}
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);
}
}
}
this.urls.add(url);
}既然这样， 那么我们只需查看remote的代码即可。
#1增加dynamic参数，dynamic:服务是否动态注册，如果设为false，注册后将显示后disable状态，需人工启用，并且服务提供者停止时，也不会自动取消册，需人工禁用。 默认：true。#2如果提供了监控中心，那么将会启用注册中心#3使用ProxyFactory将实例包装成Invoker，dubbo默认使用JavaassistRpcProxyFactory#4将invoker包装DelegateProviderMetaDataInvoker，包括invoker和ServiceConfig
if (!Constants.SCOPE_LOCAL.toString().equalsIgnoreCase(scope)) {
if (logger.isInfoEnabled()) {
logger.info("Export dubbo service " + interfaceClass.getName() + " to url " + url);
}
if (registryURLs != null && !registryURLs.isEmpty()) {
for (URL registryURL : registryURLs) {
url = url.addParameterIfAbsent("dynamic", registryURL.getParameter("dynamic")); #1
URL monitorUrl = loadMonitor(registryURL); #2
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);
}
#3
Invoker<?> invoker = proxyFactory.getInvoker(ref, (Class) interfaceClass, registryURL.addParameterAndEncoded(Constants.EXPORT_KEY, url.toFullString()));
DelegateProviderMetaDataInvoker wrapperInvoker = new DelegateProviderMetaDataInvoker(invoker, this); #4
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);
}export()方法是核心方法，根据不同协议暴露服务。下篇博客讲解
原创声明：本文系作者授权腾讯云开发者社区发表，未经许可，不得转载。
如有侵权，请联系 cloudcommunity@tencent.com 删除。
原创声明：本文系作者授权腾讯云开发者社区发表，未经许可，不得转载。
如有侵权，请联系 cloudcommunity@tencent.com 删除。
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