Spring cloud function routing api gateway null pointer exception - spring-cloud-function

Question

I have a problem with routing using API Gateway headers. I am using org.springframework.cloud.function.adapter.aws.FunctionInvoker::handleRequest as a handler request. I have two functions, they work locally. They work if I set environment variable.
If I use API Gateway headers (spring.cloud.function.definition:lowercase), I get:
{
"errorMessage": "java.lang.NullPointerException",
"errorType": "java.lang.NullPointerException",
"stackTrace": [
"org.springframework.cloud.function.adapter.aws.AWSLambdaUtils.generateMessage(AWSLambdaUtils.java:123)",
"org.springframework.cloud.function.adapter.aws.FunctionInvoker.handleRequest(FunctionInvoker.java:105)",
"java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)",
"java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)",
"java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)",
"java.base/java.lang.reflect.Method.invoke(Unknown Source)"
]
}
Example code reproducing the issue is here: https://github.com/cygi/cloudexample
POM is based on samples from Spring Cloud Function codebase (example code (https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-samples/function-sample-aws-routing). Spring Cloud Function version is 3.2.1 (sample had a SNAPSHOT version, that uses JAVA 11, which is not available in AWS Lambda, at least without docker).

Answer 1

Reverting to Spring Cloud Function 3.1.6 has resolved the problem.
Test event for AWS Lambda:
{
"body": "foo",
"httpMethod": "POST",
"isBase64Encoded": false,
"headers": {
"spring.cloud.function.definition": "uppercase"
}
}
Result on 3.2.2
{
"statusCode": 417,
"headers": null,
"body": "Failed to establish route, since neither were provided: 'spring.cloud.function.definition' as Message header or as application property or 'spring.cloud.function.routing-expression' as application property."
}
Result on 3.1.6
{
"isBase64Encoded": false,
"headers": {
"id": "758c1873-9377-25af-5ca2-84f55710ff2a",
"contentType": "application/json",
"timestamp": "1644500775689"
},
"body": "\"bbbb\"",
"statusCode": 200
}