Image building fails with an unhelpful error message when building an image from a jar that includes the launch script

[ta7uw]

I tried to execute bootBuildImage task in gradle multi-module project, but I couldn't create the image because the task failed.
I checked that bootBuildImage task in a single gradle project succeeded in my local machine.
Is executing in multi-module project the cause of the failure?

Spring Boot: 2.3.1.RELEASE
Gradle: 6.4.1

$ ./gradlew web:bootBuildImage
> Task :web:bootBuildImage
Building image 'web-app:latest'

 > Pulling builder image 'gcr.io/paketo-buildpacks/builder:base-platform-api-0.3' ..................................................
 > Pulled builder image 'gcr.io/paketo-buildpacks/builder@sha256:c8a4e4b7a6fe3aaeb4faa7731fcacae8fb91ea90e220506970e12c5a0515f3d4'
 > Pulling run image 'gcr.io/paketo-buildpacks/run:base-cnb' ..................................................
 > Pulled run image 'cloudfoundry/run@sha256:1a37642c23a2e44231bdbcfca228d20f09425ff312736e96252c7299520e5044'
 > Executing lifecycle version v0.8.0
 > Using build cache volume 'pack-cache-8ffa72a0e7c4.build'

 > Running creator
    [creator]     ===> DETECTING
    [creator]     ERROR: No buildpack groups passed detection.
    [creator]     ERROR: Please check that you are running against the correct path.
    [creator]     ERROR: failed to detect: failed to detect: no buildpacks participating

> Task :web:bootBuildImage FAILED

FAILURE: Build failed with an exception.

[wilkinsona]

Thanks for the report. Unfortunately, we can’t accurately diagnose the problem without know more about your build and its web project. It would appear that the web project doesn’t produce a binary that any of the builder’s buildpacks recognise.

If you would like us to spend some more time investigating, please spend some time providing a complete yet minimal sample that reproduces the problem. You can share it with us by pushing it to a separate repository on GitHub or by zipping it up and attaching it to this issue.

[ta7uw]

It would appear that the web project doesn’t produce a binary that any of the builder’s buildpacks recognise.

The bootJar task in web project includes launchScript.
I could create the image by excluding launchScript.

Thanks for your support!

[wilkinsona]

Thanks. Glad to hear that you figured it out. I think we should fail earlier and improve the error message so that it’s more obvious what the problem is.