Publish an Android library to Maven with aar and s

Question

Can somebody give me a hint on how to use the maven-publish gradle plugin to publish a com.android.library project/module with aar and source jar? I am able to do this with the old maven plugin - but I would like to use the new maven-publish plugin.

Answer 1

You can also use the android maven plugin. It creates the .aar, javadoc.jar, sources.jar and .pom and updates the maven-metadata.xml after uploading the files to the maven repository. I also put the script on GitHub.

apply plugin: 'com.android.library'
apply plugin: 'maven'

//Your android configuration
android {
    //...
}

//maven repository info
group = 'com.example'
version = '1.0.0'

ext {
    //Specify your maven repository url here
    repositoryUrl = 'ftp://your.maven.repository.com/maven2'
    //Or you can use 'file:\\\\C:\\Temp' or 'maven-temp' for a local maven repository
}

//Upload android library to maven with javadoc and android sources
configurations {
    deployerJars
}

//If you want to deploy to an ftp server
dependencies {
    deployerJars "org.apache.maven.wagon:wagon-ftp:2.2"
}

// custom tasks for creating source/javadoc jars
task javadoc(type: Javadoc) {
    source = android.sourceSets.main.java.srcDirs
    classpath += project.files(android.getBootClasspath().join(File.pathSeparator))
    destinationDir = file("../javadoc/")
    failOnError false
}

task javadocJar(type: Jar, dependsOn: javadoc) {
    classifier = 'javadoc'
    from javadoc.destinationDir
}

//Creating sources with comments
task androidSourcesJar(type: Jar) {
    classifier = 'sources'
    from android.sourceSets.main.java.srcDirs
}

//Put the androidSources and javadoc to the artifacts
artifacts {
    archives androidSourcesJar
    archives javadocJar
}

uploadArchives {
    repositories {
        mavenDeployer {
            configuration = configurations.deployerJars
            repository(url: repositoryUrl) {
                //if your repository needs authentication
                authentication(userName: "username", password: "password")
            }
        }
    }
}

Call it with

./gradlew uploadArchives

Answer 2

Here is my improved solution, based on other answers.

Gist: https://gist.github.com/Robyer/a6578e60127418b380ca133a1291f017

Changes from other answers:

• Changed classifier - it must be "sources" (not "source")

• Handles dependencies

  • Supports also @aar and transitive: false. In that case we set exclusion in POM to ignore all transitive dependencies of this dependency.

  • Supports also custom exclude rules on dependencies, e.g.:

    compile('com.example:something:1.0', {
        exclude group: 'com.exclude.this', module: 'some-module'
    })
    

• Doesn't need to specify artifact path manually.

Changelog:

• 27.3.2018 - Added support for api / implementation dependencies in new Gradle
• 23.11.2018 - Renamed bundleRelease to bundleReleaseAar as it was changed in new Gradle (see this answer)
• 23.11.2018 - Changed getAllDependencies to getDependencies to fix duplicated resulting entries (as mentioned in comments on my Gist).

---

apply plugin: 'maven-publish'

task androidJavadocs(type: Javadoc) {
    source = android.sourceSets.main.java.srcDirs
    classpath += project.files(android.getBootClasspath().join(File.pathSeparator))
    android.libraryVariants.all { variant ->
        if (variant.name == 'release') {
            owner.classpath += variant.javaCompile.classpath
        }
    }
    exclude '**/R.html', '**/R.*.html', '**/index.html'
}

task androidJavadocsJar(type: Jar, dependsOn: androidJavadocs) {
    classifier = 'javadoc'
    from androidJavadocs.destinationDir
}

task androidSourcesJar(type: Jar) {
    classifier = 'sources'
    from android.sourceSets.main.java.srcDirs
}

publishing {
    publications {
        maven(MavenPublication) {
            //groupId 'cz.example'
            //artifactId 'custom-artifact'
            //version = android.defaultConfig.versionName

            artifact bundleReleaseAar
            artifact androidJavadocsJar
            artifact androidSourcesJar

            pom.withXml {
                final dependenciesNode = asNode().appendNode('dependencies')

                ext.addDependency = { Dependency dep, String scope ->
                    if (dep.group == null || dep.version == null || dep.name == null || dep.name == "unspecified")
                        return // ignore invalid dependencies

                    final dependencyNode = dependenciesNode.appendNode('dependency')
                    dependencyNode.appendNode('groupId', dep.group)
                    dependencyNode.appendNode('artifactId', dep.name)
                    dependencyNode.appendNode('version', dep.version)
                    dependencyNode.appendNode('scope', scope)

                    if (!dep.transitive) {
                        // If this dependency is transitive, we should force exclude all its dependencies them from the POM
                        final exclusionNode = dependencyNode.appendNode('exclusions').appendNode('exclusion')
                        exclusionNode.appendNode('groupId', '*')
                        exclusionNode.appendNode('artifactId', '*')
                    } else if (!dep.properties.excludeRules.empty) {
                        // Otherwise add specified exclude rules
                        final exclusionNode = dependencyNode.appendNode('exclusions').appendNode('exclusion')
                        dep.properties.excludeRules.each { ExcludeRule rule ->
                            exclusionNode.appendNode('groupId', rule.group ?: '*')
                            exclusionNode.appendNode('artifactId', rule.module ?: '*')
                        }
                    }
                }

                // List all "compile" dependencies (for old Gradle)
                configurations.compile.getDependencies().each { dep -> addDependency(dep, "compile") }
                // List all "api" dependencies (for new Gradle) as "compile" dependencies
                configurations.api.getDependencies().each { dep -> addDependency(dep, "compile") }
                // List all "implementation" dependencies (for new Gradle) as "runtime" dependencies
                configurations.implementation.getDependencies().each { dep -> addDependency(dep, "runtime") }
            }
        }
    }
}

Answer 3

If you want to avoid boilerplate codes, because the maven-publish plugin do not write dependencies into pom.xml

Try this plugin: android-maven-publish

publishing {
    publications {
        mavenAar(MavenPublication) {
            from components.android
        }
    }
}

Answer 4

Here's a sample using the new maven-publish plugin.

apply plugin: 'maven-publish'

task sourceJar(type: Jar) {
    from android.sourceSets.main.java.srcDirs
    classifier "sources"
}

publishing {
    publications {
        bar(MavenPublication) {
            groupId 'com.foo'
            artifactId 'bar'
            version '0.1'
            artifact(sourceJar)
            artifact("$buildDir/outputs/aar/bar-release.aar")
        }
    }
    repositories {
        maven {
            url "$buildDir/repo"
        }
    }
}

Publish with ./gradlew clean build publish

Answer 5

A little tweak to dskinners answer with correct dependency generation:

apply plugin: 'maven-publish'

task sourceJar(type: Jar) {
    from android.sourceSets.main.java.srcDirs
    classifier "source"
}

publishing {
    publications {
        bar(MavenPublication) {
            groupId 'com.foo'
            artifactId 'bar'
            version '0.1'
            artifact(sourceJar)
            artifact("$buildDir/outputs/aar/bar-release.aar")
            pom.withXml {
                def dependenciesNode = asNode().appendNode('dependencies')
                //Iterate over the compile dependencies (we don't want the test ones), adding a <dependency> node for each
                configurations.compile.allDependencies.each {
                    if(it.group != null && (it.name != null || "unspecified".equals(it.name)) && it.version != null)
                    {
                        def dependencyNode = dependenciesNode.appendNode('dependency')
                        dependencyNode.appendNode('groupId', it.group)
                        dependencyNode.appendNode('artifactId', it.name)
                        dependencyNode.appendNode('version', it.version)
                    }
                }
            }
        }
    }
    repositories {
        maven {
            url "$buildDir/repo"
        }
    }
}

And you can change version and groupId by defining:

version = '1.0.0'
group = 'foo.bar'