Publish task fails because generated pom is invalid with duplicated tag dependencies

[hanzo2001]

Shadow Version 6.1.0

Gradle Version 6.8+

Expected Behavior

When attempting to publish a specific submodule of a multi-module project, a valid pom file should be generated in the generatePomFileFor...Publication task and the publish task should not fail.

Actual Behavior

Caveat 1: this is a Kotlin + gRPC multi-module project. Caveat 2: I am publishing one of two submodules. The other one works fine (no shadowing). Caveat 3: when removing the shadow plugin, the pom is generated correctly.

The generated pom file has two dependencies tags which causes the next task (generatePomFileFor...Publication) to fail.

If I remove all references to the shadow plugin and its configuration. The pom generation task produces the correct output.

Gradle Build Script(s)

plugins {
    kotlin("jvm") // version is managed in the rootProject
    `maven-publish`
    id("net.linguica.maven-settings") version "0.5"
    id("com.github.johnrengelman.shadow") version "6.1.0"
}

val customArtifactId = "..."
group = "..."
version = "..."
val mainClass = "..."

publishing {
    publications {
        create<MavenPublication>("...") {
            artifactId = customArtifactId
            from(components["java"])
            withoutBuildIdentifier()
            project.shadow.component(this)
        }
    }
    repositories {
        maven {
            val releases = "..."
            val snapshots = "..."
            url = uri("...")
            name = "..."
        }
    }
}

dependencies {
    implementation(project(":stub"))
    implementation(kotlin("stdlib"))
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.8")
    implementation("org.jetbrains.kotlin:kotlin-reflect:1.4.20")
    implementation("info.picocli:picocli:4.5.2")
    implementation("com.mchange:c3p0:0.9.5.2")
    implementation("org.slf4j:slf4j-api:1.7.25")
    implementation("org.jdbi:jdbi3-kotlin-sqlobject:3.16.0")
    runtimeOnly("mysql:mysql-connector-java:8.0.20")
    runtimeOnly("ch.qos.logback:logback-classic:1.2.3")
    runtimeOnly("io.grpc:grpc-netty:1.35.0")
    testImplementation("org.junit.jupiter:junit-jupiter:5.7.0")
    testImplementation("org.junit.jupiter:junit-jupiter-api:5.7.0")
    testImplementation(kotlin("test-junit5"))
    testRuntimeOnly("org.junit.jupiter", "junit-jupiter-engine", "5.5.2")
    testRuntimeOnly("ch.qos.logback:logback-classic:1.2.3")
}

tasks {
    test {
        useJUnitPlatform()
    }
    jar {
        manifest {
            attributes(
                Pair("Main-Class", mainClass)
            )
        }
    }
    shadowJar {
        archiveBaseName.set(customArtifactId)
        archiveVersion.set(project.version as String)
        archiveFileName.set("${archiveBaseName.get()}-${archiveVersion.get()}.${archiveExtension.get()}")
    }
}

tasks.withType<GenerateModuleMetadata> {
    enabled = false
}

tasks.withType<KotlinCompile>().configureEach {
    kotlinOptions {
        jvmTarget = "11"
    }
}

The rootProject build script

plugins {
    id("com.google.protobuf") version "0.8.13" apply false
    kotlin("jvm") version "1.4.20" apply false
}

ext["grpcVersion"] = "1.35.0"
ext["grpcKotlinVersion"] = "1.0.0"
ext["protobufVersion"] = "3.13.0"
ext["kotlinVersion"] = "1.4.20"

allprojects {
    repositories {
        mavenLocal()
        mavenCentral()
        jcenter()
        google()
    }
    apply(plugin = "idea")
}

Content of Shadow JAR (jar tf <jar file> - post link to GIST if too long)

The only thing missing inside the jar is the generated pom file. Everything else is there.

[hanzo2001]

UPDATE

This did not actually work

---

I have found out that when I launch the process from outside the IDE (IntelliJ), it works as expected.

If you somehow end up where I am, try launching the task from the terminal.

Output (warnings were redacted):

$ ./gradlew :server:clean :server:publish --console=plain
> Task :server:clean
> Task :stub:extractIncludeProto
> Task :protos:compileJava NO-SOURCE
> Task :protos:processResources
> Task :protos:classes
> Task :protos:jar
> Task :stub:extractProto
> Task :stub:generateProto
> Task :stub:compileKotlin
> Task :stub:compileJava
> Task :stub:processResources
> Task :stub:classes
> Task :stub:inspectClassesForKotlinIC
> Task :stub:jar
> Task :server:compileKotlin
> Task :server:compileJava NO-SOURCE
> Task :server:processResources NO-SOURCE
> Task :server:classes UP-TO-DATE
> Task :server:inspectClassesForKotlinIC
> Task :server:jar
> Task :server:generateMetadataFileFor...Publication SKIPPED
> Task :server:generatePomFileFor...Publication
> Task :server:publish...PublicationTo...Repository
> Task :server:publish

BUILD SUCCESSFUL in 40s
16 actionable tasks: 16 executed

[hanzo2001]

I am an idiot. The actual build does fail

$ ./gradlew :server:clean :server:publish --console=plain
> Task :server:clean
> Task :stub:extractIncludeProto UP-TO-DATE
> Task :protos:compileJava NO-SOURCE
> Task :protos:processResources UP-TO-DATE
> Task :protos:classes UP-TO-DATE
> Task :protos:jar UP-TO-DATE
> Task :stub:extractProto UP-TO-DATE
> Task :stub:generateProto UP-TO-DATE
> Task :stub:compileKotlin UP-TO-DATE
> Task :stub:compileJava UP-TO-DATE
> Task :stub:processResources UP-TO-DATE
> Task :stub:classes UP-TO-DATE
> Task :stub:inspectClassesForKotlinIC UP-TO-DATE
> Task :stub:jar UP-TO-DATE
> Task :server:compileKotlin
> Task :server:compileJava NO-SOURCE
> Task :server:processResources NO-SOURCE
> Task :server:classes UP-TO-DATE
> Task :server:inspectClassesForKotlinIC
> Task :server:jar
> Task :server:shadowJar
> Task :server:generateMetadataFileFor...Publication SKIPPED
> Task :server:generatePomFileFor...Publication
> Task :server:publish...PublicationTo...Repository FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':server:publish...PublicationTo...Repository'.
> Failed to publish publication '...' to repository '...'
   > Invalid publication '...': POM file is invalid. Check any modifications you have made to the POM file.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 8s
17 actionable tasks: 7 executed, 10 up-to-date

Upon inspection, the pom contains the duplicate tag

  <dependencies>
    ...
  </dependencies>
  <dependencies/>

[gamma-delta]

Hey I'm getting this issue too, did you ever figure anything out?

[aajtodd]

Seeing this as well on a multi-platform project.

kotlin {
    jvm()
    jvm("shaded") {
        attributes {
            attribute<org.gradle.api.attributes.Bundling>(
                Bundling.BUNDLING_ATTRIBUTE,
                objects.named(Bundling.SHADOWED)
            )
        }
    }
    
    ...
}


publishing {
    publications {
        getByName<MavenPublication>("shaded") {
            project.extensions.configure<com.github.jengelman.gradle.plugins.shadow.ShadowExtension>{
                component(this@getByName)
            }
        }
    }
}

[alancai98]

I ran across the duplicated tag issue in v7.1.2. Seems to be fixed in https://github.com/johnrengelman/shadow/pull/769, which is included in 8.0.0 and later. Once I upgraded, I no longer faced that issue when publishing.