Error with version 2.0.2 when multi-value header is active in alb

[LennardWolf2023]

Serverless Java Container version: 2.0.2

Implementations: Spring Boot 3

Framework version: SpringBoot 3.2.6.RELEASE

Frontend service: ALB|RestController

Deployment method: AWS Cloud Development Kit

Scenario

We tried to migrate the server less java container spring boot version we are using from version 2.0.1 to 2.0.2. We are using the framework for our lambda which is accessible by an alb, which has a certain target groups, that directs the calls to the corresponding lambda. The lambda provides a spring @RestController with Post and Get Mappings. With version 2.0.1 everything worked fine.

Expected behavior

By increasing the version in the build gradle dependencies, we wanted to migrate to the new version without any additional workaround or further action.

Actual behavior

When multi-header value (attribute on target group of lambda: lambda.multi_value_headers.enabled) are configured in the alb, the requests directing to lambda are answered with HTTP status code 502. The error occurs, when the lambda should be invoked by a HTTP request to its endpoints. Please see stack trace in full log output.

Steps to reproduce

Create a lambda with corresponding 2.0.2 version of framework, that is invoked by an alb and target group that the user can the endpoint provided by the lambdas @RestController. The multi-value headers need to be activated at the target group level.
For the setup description in https://github.com/aws/serverless-java-container/wiki/Quick-start---Spring-Boot3 is used as template.

Full log output

java.lang.NullPointerException: Cannot invoke "com.amazonaws.serverless.proxy.model.SingleValueHeaders.get(Object)" because the return value of "com.amazonaws.serverless.proxy.model.AwsProxyRequest.getHeaders()" is null
	at com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletRequest.getRemoteHost(AwsProxyHttpServletRequest.java:450)
	at org.springframework.http.server.reactive.ServletServerHttpRequest.getRemoteAddress(ServletServerHttpRequest.java:192)
	at org.springframework.http.server.reactive.DefaultServerHttpRequestBuilder.<init>(DefaultServerHttpRequestBuilder.java:76)
	at org.springframework.http.server.reactive.ServerHttpRequest.mutate(ServerHttpRequest.java:106)
	at org.springframework.http.server.reactive.ContextPathCompositeHandler.lambda$handle$1(ContextPathCompositeHandler.java:73)
	at java.base/java.util.Optional.map(Unknown Source)
	at org.springframework.http.server.reactive.ContextPathCompositeHandler.handle(ContextPathCompositeHandler.java:71)
	at org.springframework.boot.web.reactive.context.WebServerManager$DelayedInitializationHttpHandler.handle(WebServerManager.java:98)
	at org.springframework.http.server.reactive.ServletHttpHandlerAdapter.service(ServletHttpHandlerAdapter.java:199)
	at com.amazonaws.serverless.proxy.spring.embedded.ServerlessReactiveServletEmbeddedServerFactory.service(ServerlessReactiveServletEmbeddedServerFactory.java:71)
	at com.amazonaws.serverless.proxy.internal.servlet.FilterChainManager$ServletExecutionFilter.doFilter(FilterChainManager.java:374)
	at com.amazonaws.serverless.proxy.internal.servlet.FilterChainHolder.doFilter(FilterChainHolder.java:90)
	at com.amazonaws.serverless.proxy.internal.servlet.AwsLambdaServletContainerHandler.doFilter(AwsLambdaServletContainerHandler.java:154)
	at com.amazonaws.serverless.proxy.spring.SpringBootLambdaContainerHandler.handleRequest(SpringBootLambdaContainerHandler.java:183)
	at com.amazonaws.serverless.proxy.spring.SpringBootLambdaContainerHandler.handleRequest(SpringBootLambdaContainerHandler.java:56)
	at com.amazonaws.serverless.proxy.internal.LambdaContainerHandler.proxy(LambdaContainerHandler.java:215)
	at com.amazonaws.serverless.proxy.internal.LambdaContainerHandler.proxyStream(LambdaContainerHandler.java:258)
	at com.example.myapplication.StreamLambdaHandler.handleRequest(StreamLambdaHandler.kt:33)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(Unknown Source)
	at java.base/java.lang.reflect.Method.invoke(Unknown Source)
	at com.amazonaws.services.lambda.runtime.api.client.EventHandlerLoader$StreamMethodRequestHandler.handleRequest(EventHandlerLoader.java:379)
	at com.amazonaws.services.lambda.runtime.api.client.EventHandlerLoader$2.call(EventHandlerLoader.java:907)
	at com.amazonaws.services.lambda.runtime.api.client.AWSLambda.startRuntime(AWSLambda.java:239)
	at com.amazonaws.services.lambda.runtime.api.client.AWSLambda.startRuntime(AWSLambda.java:191)
	at com.amazonaws.services.lambda.runtime.api.client.AWSLambda.main(AWSLambda.java:181)

[deki]

Thanks for the bug report.

@mbfreder this looks like a regression related to #816, #827. Can you take a look please?

[deki]

@LennardWolf2023 a fix has been merged to 2.0.x and main branch. Can you please validate it using a SNAPSHOT build?

We plan to ship a 2.0.3 release tomorrow.

[LennardWolf2023]

@deki thank you for the fast response. We tried to find the corresponding snapshot, but were only able to find a snapshot for archetype underneath https://aws.oss.sonatype.org/content/repositories/snapshots, but not the spring boot3 version. Do you have a link, where we can find the snapshot.

[LennardWolf2023]

We also saw, that the release 2.0.3 was initiated. When the package is available, we try it out using the release.

[deki]

Yeah I just triggered it. Should be in Maven Central soon.

[deki]

Release is there now. Please let us now if you still see any issues.