2021-12-07 16:31:41
浏览数 (2)
- 服务发现自动配置
org.springframework.cloud.gateway.discovery.GatewayDiscoveryClientAutoConfiguration
代码语言：javascript
复制@Configuration(proxyBeanMethods = false)
@ConditionalOnProperty(name = "spring.cloud.gateway.enabled", matchIfMissing = true)
@AutoConfigureBefore(GatewayAutoConfiguration.class)
@AutoConfigureAfter(CompositeDiscoveryClientAutoConfiguration.class)
@ConditionalOnClass({ DispatcherHandler.class, CompositeDiscoveryClientAutoConfiguration.class })
@EnableConfigurationProperties
public class GatewayDiscoveryClientAutoConfiguration {
...
@Configuration(proxyBeanMethods = false)
@ConditionalOnProperty(value = "spring.cloud.discovery.reactive.enabled", matchIfMissing = true)
public static class ReactiveDiscoveryClientRouteDefinitionLocatorConfiguration {
// 根据配置启用服务发现定位器
@Bean
@ConditionalOnProperty(name = "spring.cloud.gateway.discovery.locator.enabled")
public DiscoveryClientRouteDefinitionLocator discoveryClientRouteDefinitionLocator(
ReactiveDiscoveryClient discoveryClient, DiscoveryLocatorProperties properties) {
return new DiscoveryClientRouteDefinitionLocator(discoveryClient, properties);
}
}
}
- 服务发现定位器
org.springframework.cloud.gateway.discovery.DiscoveryClientRouteDefinitionLocator
代码语言：javascript
复制public class DiscoveryClientRouteDefinitionLocator implements RouteDefinitionLocator {
...
// 服务实例
private Flux<List<ServiceInstance>> serviceInstances;
public DiscoveryClientRouteDefinitionLocator(ReactiveDiscoveryClient discoveryClient,
DiscoveryLocatorProperties properties) {
this(discoveryClient.getClass().getSimpleName(), properties);
serviceInstances = discoveryClient.getServices()
.flatMap(service -> discoveryClient.getInstances(service).collectList());
}
...
// 根据服务实例动态获取路由定义
@Override
public Flux<RouteDefinition> getRouteDefinitions() {
SpelExpressionParser parser = new SpelExpressionParser();
Expression includeExpr = parser.parseExpression(properties.getIncludeExpression());
Expression urlExpr = parser.parseExpression(properties.getUrlExpression());
Predicate<ServiceInstance> includePredicate;
if (properties.getIncludeExpression() == null || "true".equalsIgnoreCase(properties.getIncludeExpression())) {
includePredicate = instance -> true;
}
else {
includePredicate = instance -> {
Boolean include = includeExpr.getValue(evalCtxt, instance, Boolean.class);
if (include == null) {
return false;
}
return include;
};
}
return serviceInstances.filter(instances -> !instances.isEmpty()).map(instances -> instances.get(0))
.filter(includePredicate).map(instance -> {
RouteDefinition routeDefinition = buildRouteDefinition(urlExpr, instance);
final ServiceInstance instanceForEval = new DelegatingServiceInstance(instance, properties);
for (PredicateDefinition original : this.properties.getPredicates()) {
PredicateDefinition predicate = new PredicateDefinition();
predicate.setName(original.getName());
for (Map.Entry<String, String> entry : original.getArgs().entrySet()) {
String value = getValueFromExpr(evalCtxt, parser, instanceForEval, entry);
predicate.addArg(entry.getKey(), value);
}
routeDefinition.getPredicates().add(predicate);
}
for (FilterDefinition original : this.properties.getFilters()) {
FilterDefinition filter = new FilterDefinition();
filter.setName(original.getName());
for (Map.Entry<String, String> entry : original.getArgs().entrySet()) {
String value = getValueFromExpr(evalCtxt, parser, instanceForEval, entry);
filter.addArg(entry.getKey(), value);
}
routeDefinition.getFilters().add(filter);
}
return routeDefinition;
});
}
}
