Graal app falsely reports of duplicate routes after running Graal Tracing Agent

I created a micronaut app with an aim to convert it to native app. So far, the application works fine when running as a regular Java program. However, after running graalvm tracing agent to generate graalvm config files, the app strangely reports of duplicate routes, when there’s only one route in the entire app.

Steps to Reproduce

1. Create app via cli: mn create-app micronaut-two --lang=kotlin --features=graal-native-image
2. Create a kotlin data class (in this case, I called it DepartureRow), then create a Controller:

@Controller("/invoices")
class InvoiceGenerator {
    @Post("/generate")
    fun generate(@Body departures: List<DepartureRow>) = "data size: ${departures.size}"
}

1. Run ./gradlew assemble
2. Run the app with tracing agent enabled (replacing /PATH/TO/APP with your own path):

java -agentlib:native-image-agent=config-output-dir=/PATH/TO/APP/micronaut-two/src/main/resources/META-INF/native-image -jar build/libs/micronaut-two-*-all.jar

1. POST an empty JSON array to locahost:8080/invoices/generate, then close the app
2. Run ./gradlew assemble again (to make /build folder pick up files generated by tracing agent)
3. Run native-image --no-server -cp build/libs/micronaut-two-*-all.jar
4. Run the resulting executable: ./micronaut-two, and POST empty JSON array to it again. If you’re using httpie, you can do:

echo '[]' | http POST localhost:8080/invoices/generate --json

Expected Behaviour

The app should return a string: data size: 0

Actual Behaviour

The app returns HTTP 400:

{
    "_links": {
        "self": {
            "href": "/invoices/generate",
            "templated": false
        }
    },
    "message": "More than 1 route matched the incoming request. The following routes matched /invoices/generate: POST - /invoices/generate, POST - /invoices/generate"
}

Environment Information

• Operating System:

./gradlew -version

------------------------------------------------------------
Gradle 5.5
------------------------------------------------------------

Build time:   2019-06-28 17:36:05 UTC
Revision:     83820928f3ada1a3a1dbd9a6c0d47eb3f199378f

Kotlin:       1.3.31
Groovy:       2.5.4
Ant:          Apache Ant(TM) version 1.9.14 compiled on March 12 2019
JVM:          1.8.0_222 (Oracle Corporation 25.222-b08-jvmci-19.2-b02)
OS:           Mac OS X 10.14.6 x86_64

• Micronaut Version: 1.2.3
• JDK Version:

java -version
openjdk version "1.8.0_222"
OpenJDK Runtime Environment (build 1.8.0_222-20190711112007.graal.jdk8u-src-tar-gz-b08)
OpenJDK 64-Bit GraalVM CE 19.2.0.1 (build 25.222-b08-jvmci-19.2-b02, mixed mode)

Example Application

The app can be found here. FYI, the project already has all kotlin classes and config files, so you can start from step 6 onward.

[graemerocher]

For reference you should not need to run the tracing agent on a Micronaut application since Micronaut is reflection free. If you are having an issue with a third party library then use the tracing agent but generate the files into a separate directly and select only the output that relates to the library.

[doctorpangloss]

I also experience this issue. It’s a pretty common part of the workflow.