Gradle: what means that a dependency has a “promoted version”?

Gradle: Promoted Versions in Dependencies

Understanding Promoted Versions

In Gradle, a “promoted version” of a dependency refers to a version that has been specifically designated as a stable and reliable release, often for production use. This concept is typically used in conjunction with dependency management practices that involve multiple stages of releases, such as:

• Snapshot Versions: Early development versions that are constantly changing.
• Release Candidates (RCs): Versions deemed almost ready for production but may still contain minor issues.
• Stable/Promoted Versions: Fully tested and approved for production deployment.

Why Use Promoted Versions?

• Stability and Confidence: Promoted versions guarantee a level of reliability and stability, reducing the risk of introducing unexpected bugs during production deployments.
• Streamlined Development: Using promoted versions for production allows developers to focus on new features and enhancements without worrying about constantly changing dependency behavior.
• Improved Collaboration: Promotes consistency across teams by ensuring everyone uses the same, reliable versions of dependencies.

How Promoted Versions Work in Gradle

Gradle itself doesn’t have a built-in “promotion” mechanism. Instead, promoted versions are often implemented through custom conventions and practices within your project’s dependency management system. Here’s a common approach:

1. Versioning Scheme

Establish a clear versioning scheme that differentiates between snapshot, RC, and promoted versions. For instance:

1.0.0-SNAPSHOT  // Snapshot version
1.0.0-RC1         // Release candidate version
1.0.0             // Promoted/Stable version

2. Dependency Management Tools

Use dependency management tools like Maven or Ivy, which provide mechanisms for managing versions and resolving dependencies. These tools often offer features for:

• Version Ranges: Define dependency ranges to specify which versions are acceptable (e.g., [1.0.0, 1.0.99] for all versions between 1.0.0 and 1.0.99).
• Version Exclusion: Exclude specific versions of a dependency from being considered.
• Version Locking: Fix dependencies to specific versions to avoid accidental updates.

3. Continuous Integration/Continuous Deployment (CI/CD) Pipelines

Automate the process of promoting versions through CI/CD pipelines. When code is merged to a production branch, a script could automatically tag a new promoted version and publish it to a repository.

Example

Let’s imagine a project using the Spring Framework. The team uses a promoted version strategy, ensuring that all production deployments use stable versions of Spring:

dependencies {
  implementation 'org.springframework:spring-core:5.3.20' // Promoted version
}

If a newer version of Spring becomes available, say 5.4.0, it would be initially released as a snapshot or RC version. After extensive testing and validation, it could be promoted to the official 5.4.0 stable release, which would then be reflected in the dependency management system.

Conclusion

The concept of promoted versions in Gradle is a powerful way to manage dependencies, prioritize stability, and streamline development processes. By embracing this approach, you can build and deploy applications with increased confidence and efficiency.