思路
根据eureka的metadata进行自定义元数据，然后使用ribbon对该元数据进行过滤和匹配，选择server。
实现
这里使用header来传递路由信息，改造ribbon-discovery-filter-spring-cloud-starter，使其不影响静态server list。
filter
public class TagFilter extends ZuulFilter {
private static final Logger LOGGER = LoggerFactory.getLogger(TagFilter.class);
@Override
public String filterType() {
return "pre";
}
@Override
public int filterOrder() {
return 7;
}
@Override
public boolean shouldFilter() {
return true;
}
@Override
public Object run() {
RequestContext requestContext = RequestContext.getCurrentContext();
HttpServletRequest request = requestContext.getRequest();
String tag = request.getHeader("tag");
RibbonFilterContextHolder.getCurrentContext().add("tag", tag);
LOGGER.info("route {} to {}",request.getRequestURI(),tag);
return null;
}
}
predicate
public class MetadataAwarePredicate extends AbstractServerPredicate{
@Override
public boolean apply(PredicateKey input) {
if(input == null || !(input.getServer() instanceof DiscoveryEnabledServer)){
return true;
}
DiscoveryEnabledServer server = (DiscoveryEnabledServer) input.getServer();
final RibbonFilterContext context = RibbonFilterContextHolder.getCurrentContext();
final Set<Map.Entry<String, String>> attributes = Collections.unmodifiableSet(context.getAttributes().entrySet());
final Map<String, String> metadata = server.getInstanceInfo().getMetadata();
return metadata.entrySet().containsAll(attributes);
}
}
rule
public class MetadataAwareRule extends ZoneAvoidanceRule {
@Override
public AbstractServerPredicate getPredicate() {
return new MetadataAwarePredicate();
}
}
autoconfig
@Configuration
@ConditionalOnClass(DiscoveryEnabledNIWSServerList.class)
@AutoConfigureBefore(RibbonClientConfiguration.class)
@ConditionalOnProperty(value = "ribbon.filter.metadata.enabled", matchIfMissing = true)
public class RibbonMetaFilterAutoConfiguration {
@Bean
@ConditionalOnMissingBean
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public MetadataAwareRule metadataAwareRule() {
return new MetadataAwareRule();
}
}
时间： 2024-08-30 18:30:54