Cannot find JAR in outputDirectory path when using spring-boot-maven-plugin

Environment:

• Jib version: 3.1.2
• Build tool: Maven 3.6.3
• OS: mac OS 10.15.7(19H2)

Description of the issue:

When I build(or dockerBuild) with below configuration shows up this error message. Obtaining project build output files failed; make sure you have packaged your project before trying to build the image. (Did you accidentally run "mvn clean jib:build" instead of "mvn clean package jib:build"?)

<plugin>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-maven-plugin</artifactId>
  <version>2.3.2.RELEASE</version>
  <configuration>
    <outputDirectory>lib</outputDirectory>
  </configuration>
</plugin>

$ mvn clean package jib:dockerBuild
...
Caused by: java.io.IOException: Obtaining project build output files failed; make sure you have packaged your project before trying to build the image. (Did you accidentally run "mvn clean jib:build" instead of "mvn clean package jib:build"?)
...
Caused by: java.nio.file.NoSuchFileException: /path/to/my-project/target/my-application.jar.original

Build success when remove configuration.outputDirectory. It seems not read outputDirectory configuration if spring-boot-maven-plugin is used. (I guessed by looking at this code.)

Is it intended behavior?

Expected behavior: Build success when using outputDirectory in spring-boot-maven-plugin

Steps to reproduce:

1. use spring-boot-maven-plugin
2. set outputDirectory
3. mvn clean package jib:dockerBuild

[chanseokoh]

It’s a bug (or limitation) in that the output directory is unaccounted for. Note that Jib doesn’t use the repackaged Spring Boot fat JAR but a standard thin-JAR packaged by maven-jar-plugin. The current code to read Spring Boot configuration is just to correctly find the path for the thin-JAR (because the Spring Boot plugin renames the original JAR before replacing it). Some workarounds:

1. Don’t do “packaged” containerization. That is, remove <containerizingMode>packaged. We normally recommend the non-packaged mode unless there is a specific reason, because the non-packaged mode builds a bit more optimized image.
2. Don’t set <outputDirectory> in spring-boot-maven-plugin. Jib won’t make use of a Spring Boot fat JAR anyway.
3. Set <outputDirectory> in maven-jar-plugin to match the directory set in spring-boot-maven-plugin, e.g.,

       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-jar-plugin</artifactId>
         <configuration>
           <outputDirectory>lib</outputDirectory>
         </configuration>
       </plugin>
   

   (You may need to run mvn package once more.)

[elefeint]

@hellozin Thank you for the report! We are trying to reproduce the issue.