Discovery Service Filter not working

[tcarlson25]

The gateway works fine when I don't add the discovery filter property, as it picks up all services in my cluster and creates routes to them. However, when I add the property:

spring:
    cloud:
        kubernetes:
            discovery:
                filter: "metadata.labels['s1p']"

and change my service that I want to picked up from the gateway to have a label in the metadata to have s1p: "true", nothing gets picked up and I get this error instead:

org.springframework.expression.spel.SpelEvaluationException: EL1012E: Cannot index into a null value

Any ideas on what I could be doing wrong?

[salaboy]

Did you checked the other examples of these demo? Just to make sure that your labels are matching.. also which version of spring cloud are you using.. it might be that the filters are broken..

[tcarlson25]

Yeah I've looked at all the other examples. I'm using Greenwich.SR3, which pulls in spring-cloud-kubernetes: 1.0.3.RELEASE

[tcarlson25]

Here is the full error. It actually shows up when the app starts up. So it doesn't even start completely..

Caused by: org.springframework.expression.spel.SpelEvaluationException: EL1012E: Cannot index into a null value
	at org.springframework.expression.spel.ast.Indexer.getValueRef(Indexer.java:144) ~[spring-expression-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.expression.spel.ast.CompoundExpression.getValueRef(CompoundExpression.java:68) ~[spring-expression-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:89) ~[spring-expression-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:114) ~[spring-expression-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:365) ~[spring-expression-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.cloud.kubernetes.discovery.KubernetesDiscoveryClient.lambda$getServices$7(KubernetesDiscoveryClient.java:241) ~[spring-cloud-kubernetes-discovery-1.0.3.RELEASE.jar:1.0.3.RELEASE]
	at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:174) ~[na:1.8.0_212]
	at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382) ~[na:1.8.0_212]
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482) ~[na:1.8.0_212]
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472) ~[na:1.8.0_212]
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708) ~[na:1.8.0_212]
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_212]
	at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499) ~[na:1.8.0_212]
	at org.springframework.cloud.kubernetes.discovery.KubernetesDiscoveryClient.getServices(KubernetesDiscoveryClient.java:255) ~[spring-cloud-kubernetes-discovery-1.0.3.RELEASE.jar:1.0.3.RELEASE]
	at org.springframework.cloud.kubernetes.discovery.KubernetesDiscoveryClient.getServices(KubernetesDiscoveryClient.java:249) ~[spring-cloud-kubernetes-discovery-1.0.3.RELEASE.jar:1.0.3.RELEASE]
	at org.springframework.cloud.client.discovery.composite.CompositeDiscoveryClient.getServices(CompositeDiscoveryClient.java:67) ~[spring-cloud-commons-2.1.3.RELEASE.jar:2.1.3.RELEASE]
	at org.springframework.cloud.gateway.discovery.DiscoveryClientRouteDefinitionLocator.getRouteDefinitions(DiscoveryClientRouteDefinitionLocator.java:96) ~[spring-cloud-gateway-core-2.1.3.RELEASE.jar:2.1.3.RELEASE]
	at reactor.core.publisher.FluxFlatMap$FlatMapMain.onNext(FluxFlatMap.java:350) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable$IterableSubscription.slowPath(FluxIterable.java:243) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable$IterableSubscription.request(FluxIterable.java:201) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxFlatMap$FlatMapMain.onSubscribe(FluxFlatMap.java:335) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:139) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:63) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxFlatMap.subscribe(FluxFlatMap.java:97) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxMap.subscribe(FluxMap.java:62) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxMap.subscribe(FluxMap.java:62) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.Flux.subscribe(Flux.java:7799) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxFlatMap$FlatMapMain.onNext(FluxFlatMap.java:389) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable$IterableSubscription.slowPath(FluxIterable.java:243) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable$IterableSubscription.request(FluxIterable.java:201) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxFlatMap$FlatMapMain.onSubscribe(FluxFlatMap.java:335) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:139) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:63) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxFlatMap.subscribe(FluxFlatMap.java:97) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.MonoCollectList.subscribe(MonoCollectList.java:40) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.MonoMapFuseable.subscribe(MonoMapFuseable.java:59) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.MonoFlattenIterable.subscribe(MonoFlattenIterable.java:101) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxMaterialize.subscribe(FluxMaterialize.java:40) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.MonoCollectList.subscribe(MonoCollectList.java:40) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.MonoPeekFuseable.subscribe(MonoPeekFuseable.java:74) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.MonoFlattenIterable.subscribe(MonoFlattenIterable.java:101) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxDematerialize.subscribe(FluxDematerialize.java:39) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.FluxDefer.subscribe(FluxDefer.java:54) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.Flux.subscribe(Flux.java:7799) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.Flux.subscribeWith(Flux.java:7963) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.Flux.subscribe(Flux.java:7792) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.Flux.subscribe(Flux.java:7756) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at reactor.core.publisher.Flux.subscribe(Flux.java:7674) ~[reactor-core-3.2.9.RELEASE.jar:3.2.9.RELEASE]
	at org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter.lambda$onApplicationEvent$0(WeightCalculatorWebFilter.java:133) ~[spring-cloud-gateway-core-2.1.3.RELEASE.jar:2.1.3.RELEASE]
	at org.springframework.beans.factory.ObjectProvider.ifAvailable(ObjectProvider.java:93) ~[spring-beans-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter.onApplicationEvent(WeightCalculatorWebFilter.java:133) ~[spring-cloud-gateway-core-2.1.3.RELEASE.jar:2.1.3.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:402) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:359) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.cloud.gateway.route.RouteRefreshListener.reset(RouteRefreshListener.java:68) ~[spring-cloud-gateway-core-2.1.3.RELEASE.jar:2.1.3.RELEASE]
	at org.springframework.cloud.gateway.route.RouteRefreshListener.onApplicationEvent(RouteRefreshListener.java:49) ~[spring-cloud-gateway-core-2.1.3.RELEASE.jar:2.1.3.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:402) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:359) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:896) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.boot.web.reactive.context.ReactiveWebServerApplicationContext.finishRefresh(ReactiveWebServerApplicationContext.java:121) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:552) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE]
	at org.springframework.boot.web.reactive.context.ReactiveWebServerApplicationContext.refresh(ReactiveWebServerApplicationContext.java:67) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]

[salaboy]

That was definitely not happening in my examples.. so it might be broken now with those versions.. Can you please create a simple project that reproduces the problem? Or even send a PR here updating to the versions that you are using so we can have a public project failing?