EndPoint详解
EndPoint主要用于暴露一些SpringMvc内部运行的信息，通常是通过SpringMvc的请求地址获取相关信息。如/health获取健康检查信息。
简单单元测试
@Test
public void testHealth() throws Exception{
mockMvc.perform(MockMvcRequestBuilders.get("/health").contentType(MediaType.APPLICATION_JSON_UTF8)).andDo(new ResultHandler() {
@Override
public void handle(MvcResult result) throws Exception {
System.out.println(result.getResponse().getContentAsString());
}
});
}
//结果
{"status":"UP","discoveryComposite":{"description":"Discovery Client not initialized","status":"UNKNOWN","discoveryClient":{"description":"Discovery Client not initialized","status":"UNKNOWN"}},"diskSpace":{"status":"UP","total":197553815552,"free":46789115904,"threshold":10485760},"refreshScope":{"status":"UP"},"hystrix":{"status":"UP"},"consul":{"status":"UP","services":{"consul":[]},"advertiseAddress":"172.17.0.8","datacenter":"dc1","domain":"consul.","nodeName":"node-client-v-5-1","bindAddress":"0.0.0.0","clientAddress":"0.0.0.0"}}
url映射
HandlerMapping使用EndpointHandlerMapping，重写了registerHandlerMethod，主要是注册HandlerMethod时重写请求路径。
private String[] getPatterns(Object handler, RequestMappingInfo mapping) {
String path = getPath(handler);
String prefix = StringUtils.hasText(this.prefix) ? this.prefix + path : path;
Set<String> defaultPatterns = mapping.getPatternsCondition().getPatterns();
if (defaultPatterns.isEmpty()) {
return new String[] { prefix, prefix + ".json" };
}
List<String> patterns = new ArrayList<String>(defaultPatterns);
for (int i = 0; i < patterns.size(); i++) {
patterns.set(i, prefix + patterns.get(i));
}
return patterns.toArray(new String[patterns.size()]);
}
private String getPath(Object handler) {
if (handler instanceof String) {
handler = getApplicationContext().getBean((String) handler);
}
if (handler instanceof MvcEndpoint) {
return ((MvcEndpoint) handler).getPath();
}
return "";
}
如果handler时MvcEndpoint类型，则请求路径调用getPath方法获取。
健康检查为例/health
实现
public HealthEndpoint(HealthAggregator healthAggregator,
Map<String, HealthIndicator> healthIndicators) {
super("health", false);
Assert.notNull(healthAggregator, "HealthAggregator must not be null");
Assert.notNull(healthIndicators, "HealthIndicators must not be null");
CompositeHealthIndicator healthIndicator = new CompositeHealthIndicator(
healthAggregator);
for (Map.Entry<String, HealthIndicator> entry : healthIndicators.entrySet()) {
healthIndicator.addHealthIndicator(getKey(entry.getKey()), entry.getValue());
}
this.healthIndicator = healthIndicator;
}
@Override
public Health invoke() {
return this.healthIndicator.health();
}
最终回调用HealthIndicator的health()方法。而健康检查的HealthIndicator为CompositeHealthIndicator。其health方法：
@Override
public Health health() {
Map<String, Health> healths = new LinkedHashMap<String, Health>();
for (Map.Entry<String, HealthIndicator> entry : this.indicators.entrySet()) {
healths.put(entry.getKey(), entry.getValue().health());
}
return this.healthAggregator.aggregate(healths);
}
所以，HealthIndicator才是最为关键的，CompositeHealthIndicator只是将所有的HealthIndicator合并。
自定义健康检查实现，即实现HealthIndicator。
@Component
public class TestHelthIndicator extends AbstractHealthIndicator {
@Override
protected void doHealthCheck(Health.Builder builder) throws Exception {
builder.up().withDetail("test","testHealth");
}
}
"testHelthIndicator":{"status":"UP","test":"testHealth"},