Uploading to Maven Central with Gradle, Avoiding Unknown Property Error

Question

I'm trying to get my first Gradle project uploaded to Maven Central. I've followed Sonatype's documentation for this and have created an uploadArchives task for generating the metadata.

uploadArchives {
  repositories {
    mavenDeployer {
      beforeDeployment { MavenDeployment deployment -> signing.signPom(deployment) }

      repository(url: "https://oss.sonatype.org/service/local/staging/deploy/maven2/") {
        authentication(userName: ossrhUsername, password: ossrhPassword)
      }

      snapshotRepository(url: "https://oss.sonatype.org/content/repositories/snapshots/") {
        authentication(userName: ossrhUsername, password: ossrhPassword)
      }
...etc. etc.

The task references two properties, "ossrhUsername" and "ossrhPassword", which I'm supposed to define in gradle.properties; however, if I do not have a gradle.properties with these properties, the build fails with an error, even for non-uploadArchives tasks.

$ gradlew test

Could not get unknown property 'ossrhUsername' for object of type org.gradle.api.publication.maven.internal.deployer.DefaultGroovyMavenDeployer.

I would like for the build to succeed (apart from the uploadArchives task, of course) without having to define these properties in a gradle.properties file.

How do I go about doing this?

Would it be simpler to just manage a separate pom.xml exclusively for Maven Central uploading?

EDIT The identified potential duplicate is about where to externalize credentials. My question is how to ensure the Gradle build still executes successfully despite the credentials not being externalized in gradle.properties. I would like for others to be able to clone the repo and execute Gradle without having to define OSSRH credential properties.

Answer 1

Instead of referencing the property directly, I passed the property name as a String to findProperty, which eliminated the error. The API documentation indicates this method is "Incubating", but it's been around since version 2.13.

  repository(url: "https://oss.sonatype.org/service/local/staging/deploy/maven2/") {
    authentication(userName: findProperty('ossrhUsername'), password: findProperty('ossrhPassword'))
  }

  snapshotRepository(url: "https://oss.sonatype.org/content/repositories/snapshots/") {
    authentication(userName: findProperty('ossrhUsername'), password: findProperty('ossrhPassword'))
  }