Object store Gradle build cache plugin

Plugin to use an S3-compatible object store as the backend for a Gradle remote build cache.

The plugin uses the Minio Java SDK to communicate to the object store so it should work with any S3-compatible object store like Amazon S3, Digital Ocean Spaces, etc. I use it with Digital Ocean Spaces, but if folks use the plugin with other object stores please report back successes or issues and we can update the documentation / work through issues accordingly.

Usage

Apply plugin in settings.gradle

First, apply the plugin in settings.gradle

plugins {
    id "com.atkinsondev.object-store-cache" version "3.0.0"
}

For the current version, please see https://plugins.gradle.org/plugin/com.atkinsondev.object-store-cache

Configure build cache

Then configure Gradle's build caches and add the object store remote cache in settings.gradle

// Use whichever environment variable is set by your CI system
boolean isCI = Boolean.valueOf(System.getenv("GITHUB_ACTIONS"))

String cacheAccessKey = System.getenv("CACHE_ACCESS_KEY") ?: properties['cache_access_key']
String cacheSecretKey = System.getenv("CACHE_SECRET_KEY") ?: properties['cache_secret_key']

buildCache {
    local {
        enabled = !isCI
    }
    remote(com.atkinsondev.cache.ObjectStoreBuildCache) {
        endpoint = '<endpoint>'
        accessKey = cacheAccessKey
        secretKey = cacheSecretKey
        bucket = '<bucket_name>'
        push = isCI
        enabled = cacheAccessKey && cacheSecretKey
    }
}

As an example, this plugin's build uses the build cache plugin itself: https://github.com/craigatk/object-store-cache-plugin/blob/master/settings.gradle

Local credentials

Then you can pass in the access key and secret key either with those environment variables or store them in ~/.gradle/gradle.properties outside source control with those property names.

cache_access_key=<your_access_key>
cache_secret_key=<your_secret_key>

Configuration properties

All the plugin configuration properties:

Parameter	Type	Required	Default	Description
endpoint	String	yes		Endpoint of S3-compatible backend
accessKey	String	yes		Object store access key
secretKey	String	yes		Object store secret key
bucket	String	yes		Bucket name to store the cache files
autoCreateBucket	boolean	no	false	Whether to automatically create the bucket if it does not exist
expirationInDays	int	no		Configure the bucket's lifecycle policy to expire objects when they are this many days old
region	String	no	null	Region where the bucket resides (if supported by backend)

Compatibility

The plugin is compatible with Gradle 8.4 and higher and Java 21 and higher.

Changelog

• 3.0.0
  • Plugin now requires Java 21+
  • Built with Gradle 9
  • Missing cache access key or secret key now fail build (required due to API changes in Gradle 9). Add enabled = cacheAccessKey && cacheSecretKey to the plugin Gradle config to disable the remote cache if those fields are not available.
• 2.1.0
  • Upgrading to Minio 8
  • Plugin now requires Gradle 8.4+
• 2.0.0
  • BREAKING CHANGE: Plugin now requires Java 17+ and Gradle 8+
• 1.4.0
  • Upgrading Kotlin dependency to 1.7.21
• 1.3.1
  • Upgrading Kotlin dependency to 1.6.20 and build to Gradle 7.5.1
• 1.2.0
  • Switching from jCenter to Maven Central
• 1.1.2
  • Improving error message when access or secret key is missing
• 1.0.0
  • Initial release