As of its 5.3 version, Gradle is able to generate and consume Gradle-specific build metadata. It's an opt-in feature for now, but it will be enabled by default with Gradle 6.0.

Should we produce and publish this metadata for our 5.2.0 release?

Here is the module.json file published for spring-webflux:

{
  "formatVersion": "1.0",
  "component": {
    "group": "org.springframework",
    "module": "spring-webflux",
    "version": "5.2.0.BUILD-SNAPSHOT",
    "attributes": {
      "org.gradle.status": "integration"
    }
  },
  "createdBy": {
    "gradle": {
      "version": "5.6",
      "buildId": "tnw2jjpho5a5jfyvqcxsiinl3u"
    }
  },
  "variants": [
    {
      "name": "apiElements",
      "attributes": {
        "org.gradle.category": "library",
        "org.gradle.dependency.bundling": "external",
        "org.gradle.jvm.version": 8,
        "org.gradle.libraryelements": "jar",
        "org.gradle.usage": "java-api",
        "org.jetbrains.kotlin.localToProject": "public",
        "org.jetbrains.kotlin.platform.type": "jvm"
      },
      "dependencies": [
        {
          "group": "org.springframework",
          "module": "spring-beans",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-core",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-web",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "io.projectreactor",
          "module": "reactor-core",
          "version": {
            "requires": "3.3.0.M3"
          }
        }
      ],
      "files": [
        {
          "name": "spring-webflux-5.2.0.BUILD-SNAPSHOT.jar",
          "url": "spring-webflux-5.2.0.BUILD-SNAPSHOT.jar",
          "size": 812464,
          "sha1": "2ba63ce11e96bccd35154fdc683101bd3414bc56",
          "md5": "7ed44177912810577066d4e262f8273d"
        }
      ]
    },
    {
      "name": "runtimeElements",
      "attributes": {
        "org.gradle.category": "library",
        "org.gradle.dependency.bundling": "external",
        "org.gradle.jvm.version": 8,
        "org.gradle.libraryelements": "jar",
        "org.gradle.usage": "java-runtime",
        "org.jetbrains.kotlin.localToProject": "public",
        "org.jetbrains.kotlin.platform.type": "jvm"
      },
      "dependencies": [
        {
          "group": "org.springframework",
          "module": "spring-beans",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-core",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-web",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "io.projectreactor",
          "module": "reactor-core",
          "version": {
            "requires": "3.3.0.M3"
          }
        }
      ],
      "files": [
        {
          "name": "spring-webflux-5.2.0.BUILD-SNAPSHOT.jar",
          "url": "spring-webflux-5.2.0.BUILD-SNAPSHOT.jar",
          "size": 812464,
          "sha1": "2ba63ce11e96bccd35154fdc683101bd3414bc56",
          "md5": "7ed44177912810577066d4e262f8273d"
        }
      ]
    }
  ]
}

Here is the module.json file for our Java Platform (also exported as a Maven BOM):

{
  "formatVersion": "1.0",
  "component": {
    "group": "org.springframework",
    "module": "spring-framework-bom",
    "version": "5.2.0.BUILD-SNAPSHOT",
    "attributes": {
      "org.gradle.status": "integration"
    }
  },
  "createdBy": {
    "gradle": {
      "version": "5.6",
      "buildId": "536e76sdo5cndbduo2qqzgbcja"
    }
  },
  "variants": [
    {
      "name": "apiElements",
      "attributes": {
        "org.gradle.category": "platform",
        "org.gradle.usage": "java-api"
      },
      "dependencyConstraints": [
        {
          "group": "org.springframework",
          "module": "spring-aop",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-aspects",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-beans",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-context",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-context-indexer",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-context-support",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-core",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-expression",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-instrument",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-jcl",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-jdbc",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-jms",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-messaging",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-orm",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-oxm",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-test",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-tx",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-web",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-webflux",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-webmvc",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-websocket",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        }
      ]
    },
    {
      "name": "runtimeElements",
      "attributes": {
        "org.gradle.category": "platform",
        "org.gradle.usage": "java-runtime"
      },
      "dependencyConstraints": [
        {
          "group": "org.springframework",
          "module": "spring-aop",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-aspects",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-beans",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-context",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-context-indexer",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-context-support",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-core",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-expression",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-instrument",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-jcl",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-jdbc",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-jms",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-messaging",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-orm",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-oxm",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-test",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-tx",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-web",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-webflux",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-webmvc",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        },
        {
          "group": "org.springframework",
          "module": "spring-websocket",
          "version": {
            "requires": "5.2.0.BUILD-SNAPSHOT"
          }
        }
      ]
    }
  ]
}

Note that all the generated POMs are slightly changed with the following:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <!-- This module was also published with a richer model, Gradle metadata,  -->
  <!-- which should be used instead. Do not delete the following line which  -->
  <!-- is to indicate to Gradle or any Gradle module metadata file consumer  -->
  <!-- that they should prefer consuming it instead. -->
  <!-- do-not-remove: published-with-gradle-metadata -->
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.springframework</groupId>
  <artifactId>spring-framework-bom</artifactId>

Comment From: bclozel

See jfrog/build-info#247

Comment From: bclozel

Reverting and reopening since publishing Gradle metadata seems to fails for a combination of "Gradle < 6.0" and "using the spring dependency management plugin". Here's a repro project:

plugins {
    id 'java'
    id "io.spring.dependency-management" version "1.0.8.RELEASE"
}

repositories {
  mavenCentral()
  maven { url 'https://repo.spring.io/milestone' }
  maven { url 'https://repo.spring.io/snapshot' }
}

dependencyManagement {
     imports {
          mavenBom 'org.springframework:spring-framework-bom:5.2.2.BUILD-SNAPSHOT'
     }
}

dependencies {
  implementation 'org.springframework:spring-core'
}

task testbom {

 doLast {
   def managedVersions = dependencyManagement.managedVersions
   def springCoreVersion = managedVersions['org.springframework:spring-core']
   println springCoreVersion
 }

}

This is failing with:

> Task :testbom FAILED

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/bclozel/workspace/tmp/gradle-metadata/build.gradle' line: 25

* What went wrong:
Execution failed for task ':testbom'.
> Could not resolve all dependencies for configuration ':detachedConfiguration1'.
   > Could not resolve org.springframework:spring-framework-bom:5.2.2.BUILD-SNAPSHOT.
     Required by:
         project :
      > Cannot choose between the following variants of org.springframework:spring-framework-bom:5.2.2.BUILD-SNAPSHOT:
          - enforcedRuntimeElements
          - runtimeElements
        All of them match the consumer attributes:
          - Variant 'enforcedRuntimeElements' capability org.springframework:spring-framework-bom:5.2.2.BUILD-SNAPSHOT:
              - Unmatched attributes:
                  - Found org.gradle.category 'enforced-platform' but wasn't required.
                  - Found org.gradle.status 'integration' but wasn't required.
                  - Found org.gradle.usage 'java-runtime' but wasn't required.
          - Variant 'runtimeElements' capability org.springframework:spring-framework-bom:5.2.2.BUILD-SNAPSHOT:
              - Unmatched attributes:
                  - Found org.gradle.category 'platform' but wasn't required.
                  - Found org.gradle.status 'integration' but wasn't required.
                  - Found org.gradle.usage 'java-runtime' but wasn't required.

As this combination (Gradle version and plugin) is quite popular, I'm unpublishing this metadata for now. We might consider publishing that now in a future minor version as we're moving on with the maintenance versions in this branch.

Comment From: bclozel

Closed with 9bd60f6554d0193a74