Issue: application.yml Not Loaded Correctly in Fat JAR Built with Shadow Plugin

[kaziasifjawwad]

Issue: application.yml Not Loaded Correctly in Fat JAR Built with Shadow Plugin

Description

I encountered an issue where the application.yml file is not being loaded correctly when packaging a Spring Boot application into a fat JAR using the com.github.johnrengelman.shadow plugin.

Steps to Reproduce

1. Project Setup:

   • Spring Boot version: 2.7.7
   • Gradle version: 8.10 (Replace with your version)
   • Shadow plugin version: 8.1.1
   • Java version: 17

2. Build the Fat JAR:

   • I used the following Gradle configuration to build the fat JAR:

     plugins {
         id 'application'
         id 'org.openjfx.javafxplugin' version '0.0.13'
         id 'com.github.johnrengelman.shadow' version '8.1.1'
     }
     
     shadowJar {
         archiveClassifier.set('all')
         mergeServiceFiles()
     
         from('src/main/resources') {
             into 'BOOT-INF/classes/'
             include '**/*.yml'
         }
     }
     
     application {
         mainClass = 'com.jawwad.posrestaurant.PosRestaurantApplication'
     }
     

3. Run the Application:

   • After building the fat JAR, I executed it using:

     java -jar build/libs/posrestaurant-0.0.1-SNAPSHOT-all.jar
     

Observed Behavior

• The application.yml file is present in both the root and BOOT-INF/classes/ directories within the JAR.
• Despite this, Spring Boot fails to resolve placeholders defined in application.yml (e.g., ${backend.baseurl}) during the application startup.
• The application throws an IllegalArgumentException indicating that the placeholder could not be resolved.

Expected Behavior

• Spring Boot should correctly load application.yml from BOOT-INF/classes/ and resolve all placeholders defined within it.

Additional Information

• The application runs correctly when built using the bootJar task or when using the non-fat JAR.
• The issue appears to be specific to the configuration when using the Shadow plugin.

Logs and Output

Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'backend.baseurl' in value "${backend.baseurl}"
    at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:180)
    ...

[kyuri-code]

Same Issue to me, hoping any updates.

[Goooler]

@kaziasifjawwad What should maven-shade-plugin do for this?

[Goooler]

I believe you could move src/main/resources/application.yml into src/main/resources/BOOT-INF/classes/application.yml and remove

  from('src/main/resources') {
    into 'BOOT-INF/classes/'
    include '**/*.yml'
  }

[Goooler]

This case looks like the correct behavior like Jar task did, see #1296.