Jersey : AwsProxyHttpServletResponseWriter : NullPointerException for Status that is not present in Response.StatusType

[anmolk6]

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Serverless Java Container version: 1.9

Implementations: Jersey

Framework version: jersey-media-json-jackson : 2.37

Frontend service: ALB

Deployment method: Console

Scenario

I am trying to return 422 statusCode in specific scenario using javax.ws.rs.core Response.status(422).entity(response).build();

Expected behavior

It should through exception with status 422

Actual behavior

502Bad Gateway
{
"message": "Gateway timeout"
}

Steps to reproduce

@POST
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public Response createPet(final Pet newPet) {
    if (newPet.getName() == null || newPet.getBreed() == null) {
        return Response.status(422).entity(new Error("Invalid name or breed")).build();
    }
    Pet dbPet = newPet;
    dbPet.setId(UUID.randomUUID().toString());
    return Response.status(200).entity(dbPet).build();
}

Full log output

"java.lang.NullPointerException: null\n\tat com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletResponseWriter.writeResponse(AwsProxyHttpServletResponseWriter.java:77)\n\tat com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletResponseWriter.writeResponse(AwsProxyHttpServletResponseWriter.java:36)\n\tat com.amazonaws.serverless.proxy.internal.LambdaContainerHandler.proxy(LambdaContainerHandler.java:222)\n\tat com.amazonaws.serverless.proxy.internal.LambdaContainerHandler.proxyStream(LambdaContainerHandler.java:257)\n\tat com.telstra.digitalservices.lambda.Handler.handleRequest(Handler.java:42)\n\tat java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)\n\tat java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)\n\tat java.base/java.lang.reflect.Method.invoke(Unknown Source)\n\tat lambdainternal.EventHandlerLoader$StreamMethodRequestHandler.handleRequest(EventHandlerLoader.java:375)\n\tat lambdainternal.EventHandlerLoader$2.call(EventHandlerLoader.java:899)\n\tat lambdainternal.AWSLambda.startRuntime(AWSLambda.java:268)\n\tat lambdainternal.AWSLambda.startRuntime(AWSLambda.java:206)\n\tat lambdainternal.AWSLambda.main(AWSLambda.java:200)\n"

Analysis

As per analysis it's failing while getting reason phrase on
https://github.com/awslabs/aws-serverless-java-container/blob/main/aws-serverless-java-container-core/src/main/java/com/amazonaws/serverless/proxy/internal/servlet/AwsProxyHttpServletResponseWriter.java#L77

422 is not present by default in provided enum , so fromStatusCode(int statusCode) is returning null as per its implementation

public static Status fromStatusCode(int statusCode) {
for (Status s : values()) {
if (s.code == statusCode) {
return s;
}
}
return null;
}

And null.getReasonPhrase is causing this nullPointerException.

Could you please suggest ways to handle this?

[deki]

Thanks for the issue report. Let's fix that by adding a null check and omitting the reason phrase in this case.

[anmolk6]

Fix in this PR is tested with ALB : #498

[deki]

Released as part of version 1.9.1.