zuul网关
zuul自定义过滤器
- 继承ZuulFilter类,实现其方法filterType()、filterOrder()、shouldFilter()、run()
- filterType()表示过滤器的类型:pre-前置过滤器,用于请求处理前;route-路由过滤器,用于路由请求;post-后置过滤器,用于响应请求;error-错误过滤器,用于处理错误情况。
- filterOrder()表示过滤器的执行顺序,较小意味着先执行
- shouldFilter()表示是否执行过滤器的逻辑,可以编写逻辑确定是否执行过滤器
- run(),过滤器的实际执行逻辑
java
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
public class CustomFilter extends ZuulFilter {
@Override
public String filterType() {
return "pre"; // 前置过滤器
}
@Override
public int filterOrder() {
return 1; // 执行顺序,数字越小越早执行
}
@Override
public boolean shouldFilter() {
return true; // 在该方法中可以定义过滤器是否执行的逻辑
}
@Override
public Object run() {
// 获取请求的信息
RequestContext ctx = RequestContext.getCurrentContext();
HttpServletRequest request = ctx.getRequest();
String uri = request.getRequestURI();
// 获取请求信息、响应信息等
// 对请求或响应进行处理
if(auth(ctd)){
ctx.setSendZuulResponse(false); // 不将请求路由到后端服务
ctx.setResponseStatusCode("401");
ctx.setResponseBody("Access Denied"); // 设置响应内容
ctx.set("responseFiltered", true); // 标记该请求已被过滤
}
return null;
}
}
hystrix和ribbon时间
Ribbon超时时间
Hystrix超时时间
配置文件
调用过程
RibbonAutoConfiguration自动配置
java
// 注入属性
@Autowired(required = false)
private List<RibbonClientSpecification> configurations = new ArrayList<>();
FeignAutoConfiguration自动配置
java
@Bean
public FeignContext feignContext() {
FeignContext context = new FeignContext();
context.setConfigurations(this.configurations);
return context;
}
RibbonEurekaAutoConfiguration
SendErrorFilter过滤器
sendErrorFilter.ran请求上下为true则不执行这个默认过滤器
java
public class SendErrorFilter extends ZuulFilter {
private static final Log log = LogFactory.getLog(SendErrorFilter.class);
protected static final String SEND_ERROR_FILTER_RAN = "sendErrorFilter.ran";
@Value("${error.path:/error}")
private String errorPath;
@Override
public String filterType() {
return ERROR_TYPE;
}
@Override
public int filterOrder() {
return SEND_ERROR_FILTER_ORDER;
}
@Override
public boolean shouldFilter() {
RequestContext ctx = RequestContext.getCurrentContext();
// only forward to errorPath if it hasn't been forwarded to already
return ctx.getThrowable() != null
&& !ctx.getBoolean(SEND_ERROR_FILTER_RAN, false);
}
@Override
public Object run() {
try {
RequestContext ctx = RequestContext.getCurrentContext();
// 获取异常信息
ExceptionHolder exception = findZuulException(ctx.getThrowable());
HttpServletRequest request = ctx.getRequest();
request.setAttribute("javax.servlet.error.status_code", exception.getStatusCode());
// 打印什么原因导致的异常异常的信息
log.warn("Error during filtering", exception.getThrowable());
request.setAttribute("javax.servlet.error.exception", exception.getThrowable());
if (StringUtils.hasText(exception.getErrorCause())) {
request.setAttribute("javax.servlet.error.message", exception.getErrorCause());
}
RequestDispatcher dispatcher = request.getRequestDispatcher(
this.errorPath);
if (dispatcher != null) {
ctx.set(SEND_ERROR_FILTER_RAN, true);
if (!ctx.getResponse().isCommitted()) {
ctx.setResponseStatusCode(exception.getStatusCode());
dispatcher.forward(request, ctx.getResponse());
}
}
}
catch (Exception ex) {
ReflectionUtils.rethrowRuntimeException(ex);
}
return null;
}
protected ExceptionHolder findZuulException(Throwable throwable) {
if (throwable.getCause() instanceof ZuulRuntimeException) {
Throwable cause = null;
if (throwable.getCause().getCause() != null) {
cause = throwable.getCause().getCause().getCause();
}
if (cause instanceof ClientException && cause.getCause() != null
&& cause.getCause().getCause() instanceof SocketTimeoutException) {
ZuulException zuulException = new ZuulException("", 504,
ZuulException.class.getName() + ": Hystrix Readed time out");
return new ZuulExceptionHolder(zuulException);
}
// this was a failure initiated by one of the local filters
if(throwable.getCause().getCause() instanceof ZuulException) {
return new ZuulExceptionHolder((ZuulException) throwable.getCause().getCause());
}
}
if (throwable.getCause() instanceof ZuulException) {
// wrapped zuul exception
return new ZuulExceptionHolder((ZuulException) throwable.getCause());
}
if (throwable instanceof ZuulException) {
// exception thrown by zuul lifecycle
return new ZuulExceptionHolder((ZuulException) throwable);
}
// fallback
return new DefaultExceptionHolder(throwable);
}
protected interface ExceptionHolder {
Throwable getThrowable();
default int getStatusCode() {
return HttpStatus.INTERNAL_SERVER_ERROR.value();
}
default String getErrorCause() {
return null;
}
}
protected static class DefaultExceptionHolder implements ExceptionHolder {
private final Throwable throwable;
public DefaultExceptionHolder(Throwable throwable) {
this.throwable = throwable;
}
@Override
public Throwable getThrowable() {
return this.throwable;
}
}
protected static class ZuulExceptionHolder implements ExceptionHolder {
private final ZuulException exception;
public ZuulExceptionHolder(ZuulException exception) {
this.exception = exception;
}
@Override
public Throwable getThrowable() {
return this.exception;
}
@Override
public int getStatusCode() {
return this.exception.nStatusCode;
}
@Override
public String getErrorCause() {
return this.exception.errorCause;
}
}
public void setErrorPath(String errorPath) {
this.errorPath = errorPath;
}
}
@EnableZuulServer
ZuulServerAutoConfiguration自动注入的类
将应用程序设置为没有任何内置反向代理特性的通用Zuul服务器。到Zuul服务器的路由可以通过ZuulProperties配置(默认情况下没有)
HasFeatures
@EnableZuulProxy
设置一个Zuul服务器端点,并在其中安装一些反向代理过滤器,这样它就可以将请求转发到后端服务器。后端可以通过配置手工注册,也可以通过DiscoveryClient注册。
- ServiceRouteMapper
- DiscoveryClientRouteLocator
- HasFeatures
- HttpClientConfiguration(Import)
- ApacheHttpClientConnectionManagerFactory
- HttpClientBuilder
- ApacheHttpClientFactory
- RibbonCommandFactoryConfiguration.HttpClientRibbonConfiguration.class(Import)
- RibbonCommandFactory
- PreDecorationFilter
- RibbonRoutingFilter
- SimpleHostRoutingFilter