micronaut-core: default cli-app project doesn't work with GraalVM because of PicoCLI

Update: picocli-codegen 3.7.0 is now available from Maven Central.

The picocli-codegen README now has usage instructions with code snippets for Gradle and Maven to generate a cli-reflect.json file automatically as part of the build.

@graemerocher I believe this goes a long way towards what you are looking for in terms of tooling to make Micronaut + Graal work more out of the box. What is left is documentation:

• point to the picocli-codegen README. See PR https://github.com/micronaut-projects/micronaut-core/pull/760
• note that the native-image -H:ReflectionConfigurationFiles option takes multiple comma-separated files, so users can specify both the config file generated manually with GraalClassLoadingAnalyzer and the one generated during the build by picocli-codegen. See PR https://github.com/micronaut-projects/micronaut-core/pull/761

@t-buss One way to fix the problem is to add the 'info.picocli:picocli:4.0.0-alpha-3' dependency to the generateConfig classpath.

Alternatively use the same version of picocli and picocli-codegen that is on the runtime classpath to generate the reflect-config.

Hi, not sure if this is really resolved, as I am running in some problems that seem to be related:

>>> $ sdk current java

Using java version 19.0.0-grl
>>> $ sdk current micronaut

Using micronaut version 1.1.1
>>> $ mn create-cli-app example.git-star --features=graal-native-image,http-client
| Generating Java project...
| Application created at /home/tbuss/Repos/transformer/git-star
>>> $ cd git-star/
>>> git-star/ $ ls
build.gradle      Dockerfile  gradlew*      micronaut-cli.yml  src/
docker-build.sh*  gradle/     gradlew.bat*  settings.gradle
>>> git-star/ $ vim Dockerfile
>>> git-star/ $ ./gradlew assemble

BUILD SUCCESSFUL in 8s
10 actionable tasks: 10 executed
>>> git-star/ $ ./docker-build.sh
Sending build context to Docker daemon  54.97MB
Step 1/8 : FROM oracle/graalvm-ce:1.0.0-rc15 as graalvm
 ---> e319c61ef084
Step 2/8 : COPY . /home/app/git-star
 ---> 59549105f0d3
Step 3/8 : WORKDIR /home/app/git-star
 ---> Running in c93a13623cb6
Removing intermediate container c93a13623cb6
 ---> bbe702a2b1d8
Step 4/8 : RUN native-image --no-server -cp build/libs/git-star-*.jar example.GitStarCommand
 ---> Running in d57190f045f8
[git-star:8]    classlist:   5,227.33 ms
[git-star:8]        (cap):   1,276.30 ms
[git-star:8]        setup:   2,867.72 ms
[git-star:8]   (typeflow):  38,611.84 ms
[git-star:8]    (objects):  56,966.59 ms
[git-star:8]   (features):   2,149.31 ms
[git-star:8]     analysis: 100,434.50 ms
[git-star:8]     universe:   1,967.74 ms
[git-star:8]      (parse):   6,614.95 ms
[git-star:8]     (inline):  18,425.55 ms
[git-star:8]    (compile):  57,505.04 ms
[git-star:8]      compile:  86,515.65 ms
[git-star:8]        image:   8,141.26 ms
[git-star:8]        write:   1,379.17 ms
[git-star:8]      [total]: 207,047.26 ms
Removing intermediate container d57190f045f8
 ---> 8f6ab5e72833
Step 5/8 : FROM frolvlad/alpine-glibc
 ---> dbb18830337d
Step 6/8 : EXPOSE 8080
 ---> Using cache
 ---> 1047f8548cd8
Step 7/8 : COPY --from=graalvm /home/app/git-star .
 ---> ae59fec935c0
Step 8/8 : ENTRYPOINT ["./git-star", "-v"]
 ---> Running in 99d89b148fb8
Removing intermediate container 99d89b148fb8
 ---> ee2ff9fb1b73
Successfully built ee2ff9fb1b73
Successfully tagged git-star:latest


To run the docker container execute:
    $ docker run -p 8080:8080 git-star
>>> git-star/ $ docker run git-star
Exception in thread "main" picocli.CommandLine$InitializationException: Could not instantiate class example.GitStarCommand: io.micronaut.context.exceptions.NoSuchBeanException: No bean of type [example.GitStarCommand] exists. Ensure the class is declared a bean and if you are using Java or Kotlin make sure you have enabled annotation processing.
	at picocli.CommandLine$DefaultFactory.create(CommandLine.java:2848)
	at picocli.CommandLine$Model$CommandReflection.extractCommandSpec(CommandLine.java:4835)
	at picocli.CommandLine$Model$CommandSpec.forAnnotatedObject(CommandLine.java:3142)
	at picocli.CommandLine.<init>(CommandLine.java:147)
	at picocli.CommandLine.run(CommandLine.java:1792)
	at picocli.CommandLine.run(CommandLine.java:1716)
	at io.micronaut.configuration.picocli.PicocliRunner.run(PicocliRunner.java:139)
	at io.micronaut.configuration.picocli.PicocliRunner.run(PicocliRunner.java:117)
	at example.GitStarCommand.main(GitStarCommand.java:19)
Caused by: io.micronaut.context.exceptions.NoSuchBeanException: No bean of type [example.GitStarCommand] exists. Ensure the class is declared a bean and if you are using Java or Kotlin make sure you have enabled annotation processing.
	at io.micronaut.configuration.picocli.MicronautFactory.lambda$create$0(MicronautFactory.java:71)
	at java.util.Optional.orElseThrow(Optional.java:290)
	at io.micronaut.configuration.picocli.MicronautFactory.create(MicronautFactory.java:71)
	at picocli.CommandLine$DefaultFactory.create(CommandLine.java:2847)
	... 8 more

This seems to be an error with the reflective access of PicoCLI. I also tried what the PicoCLI README suggested and added dependencies and Gradle task:

dependencies {
    compile 'info.picocli:picocli:4.0.0-alpha-3'
    generateConfig 'info.picocli:picocli-codegen:4.0.0-alpha-3'
}

task(generateGraalReflectionConfig, dependsOn: 'classes', type: JavaExec) {
    main = 'picocli.codegen.aot.graalvm.ReflectionConfigGenerator'
    classpath = configurations.generateConfig + sourceSets.main.runtimeClasspath
    def outputFile = "${buildDir}/resources/main/META-INF/native-image/${project.group}/${project.name}/reflect-config.json"
    args = ["--output=$outputFile", 'example.GitStarCommand']
}
assemble.dependsOn generateGraalReflectionConfig

which resulted in this error message:

> Task :generateGraalReflectionConfig FAILED
Exception in thread "main" java.lang.NoSuchMethodError: picocli.CommandLine.execute([Ljava/lang/String;)I
        at picocli.codegen.aot.graalvm.ReflectionConfigGenerator.main(ReflectionConfigGenerator.java:92)

Help would be appreciated, and I would also volunteer to update the docs accordingly. Thanks in advance!

@remkop ok no worries, will do manual merge