Gradle Docker Jib Integration

•Purpose
•When to Use
•Quick Start
•Instructions
•Requirements
•See Also

Purpose

Build Docker images efficiently using Google's Jib plugin without requiring Docker installation, Dockerfiles, or container knowledge. Jib automatically optimizes layers and handles multi-architecture builds for local and registry deployments.

When to Use

Use this skill when you need to:

•Build Docker images without Docker daemon or Dockerfiles
•Containerize Spring Boot microservices efficiently
•Create multi-architecture images (amd64, arm64) for cloud deployment
•Optimize Docker layer caching for faster builds
•Push images to GCR, Docker Hub, or private registries
•Integrate Docker image building in CI/CD pipelines

Quick Start

Add Jib plugin to build.gradle.kts:

kotlin

plugins {
    id("com.google.cloud.tools.jib") version "3.4.4"
}

jib {
    from {
        image = "eclipse-temurin:21-jre-alpine"
    }
    to {
        image = "gcr.io/my-project/my-app"
        tags = setOf("latest", project.version.toString())
    }
    container {
        jvmFlags = listOf("-Xmx512m", "-Xms256m")
        ports = listOf("8080")
        user = "nobody"
    }
}

Build to local Docker:

bash

./gradlew jibDockerBuild

Build and push to registry:

bash

./gradlew jib

Instructions

Step 1: Add Jib Plugin

Add to build.gradle.kts:

kotlin

plugins {
    id("com.google.cloud.tools.jib") version "3.4.4"
}

Or in build.gradle:

groovy

plugins {
    id 'com.google.cloud.tools.jib' version '3.4.4'
}

Step 2: Configure Base Image

Choose appropriate base image:

For Spring Boot (JRE only):

kotlin

jib {
    from {
        image = "eclipse-temurin:21-jre-alpine"
        // or for ARM support
        // image = "eclipse-temurin:21-jre"
    }
}

For distroless (minimal):

kotlin

jib {
    from {
        image = "gcr.io/distroless/java21-debian12"
    }
}

See references/detailed-guide.md for base image selection guide.

Step 3: Configure Target Registry

Google Container Registry (GCR):

kotlin

jib {
    to {
        image = "gcr.io/my-project/my-app"
        tags = setOf("latest", project.version.toString())
    }
}

Docker Hub:

kotlin

jib {
    to {
        image = "docker.io/myusername/my-app"
        auth {
            username = System.getenv("DOCKER_USERNAME")
            password = System.getenv("DOCKER_PASSWORD")
        }
    }
}

Private registry:

kotlin

jib {
    to {
        image = "registry.company.com/my-app"
        credHelper = "gcr"  // or "ecr-login", "docker-credential-gcr"
    }
}

Step 4: Configure Container Settings

JVM flags and ports:

kotlin

jib {
    container {
        jvmFlags = listOf(
            "-Xmx512m",
            "-Xms256m",
            "-Dspring.profiles.active=prod",
            "-XX:+UseContainerSupport"
        )
        ports = listOf("8080", "8081")
        labels = mapOf(
            "maintainer" to "team@company.com",
            "version" to project.version.toString()
        )
        user = "nobody"
        workingDirectory = "/app"
    }
}

Environment variables:

kotlin

jib {
    container {
        environment = mapOf(
            "PORT" to "8080",
            "ENV" to "production"
        )
    }
}

See references/detailed-guide.md for advanced container configuration.

Step 5: Configure Multi-Architecture Images

Build for multiple platforms:

kotlin

jib {
    from {
        image = "eclipse-temurin:21-jre"
        platforms {
            platform {
                architecture = "amd64"
                os = "linux"
            }
            platform {
                architecture = "arm64"
                os = "linux"
            }
        }
    }
}

Step 6: Set Up Authentication

Using credential helpers:

bash

# Install credential helper
gcloud auth configure-docker

# Or for Docker Hub
docker login

Using environment variables:

bash

export DOCKER_USERNAME=myuser
export DOCKER_PASSWORD=mypassword
./gradlew jib

In CI/CD:

yaml

# GitHub Actions
- name: Build and Push
  run: ./gradlew jib
  env:
    DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
    DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}

Step 7: Build Images

Build to local Docker daemon:

bash

./gradlew jibDockerBuild
docker images  # Verify image exists

Build and push to registry:

bash

./gradlew jib

Build OCI tar archive:

bash

./gradlew jibBuildTar
# Creates build/jib-image.tar

Step 8: Configure Multi-Module Projects

For multi-module projects, configure Jib in specific modules:

kotlin

// app/build.gradle.kts
plugins {
    id("com.google.cloud.tools.jib")
}

jib {
    to {
        image = "gcr.io/my-project/${project.name}"
    }
    container {
        mainClass = "com.example.app.MainKt"
    }
}

// service-a/build.gradle.kts
plugins {
    id("com.google.cloud.tools.jib")
}

jib {
    to {
        image = "gcr.io/my-project/${project.name}"
    }
}

See references/detailed-guide.md for complete multi-module setup.

Step 9: Optimize Build Performance

Enable caching:

kotlin

jib {
    // Use timestamp for better layer caching
    container {
        creationTime = "USE_CURRENT_TIMESTAMP"
    }
}

Skip unchanged layers: Jib automatically caches layers by content hash - no configuration needed.

Requirements

•Gradle: 7.0+ (8.11+ recommended)
•Java: JDK 11+ (21 recommended)
•Jib Plugin: 3.4.4+
•
Authentication:
- •Docker credential helper (recommended)
- •Environment variables
- •Docker config (~/.docker/config.json)
•
For Local Docker:
- •Docker daemon running
- •jibDockerBuild command
•
For Registry Push:
- •Valid credentials
- •Network access to registry

gradle-docker-jib

Gradle Docker Jib Integration

Table of Contents

Purpose

When to Use

Quick Start

Instructions

Step 1: Add Jib Plugin

Step 2: Configure Base Image

Step 3: Configure Target Registry

Step 4: Configure Container Settings

Step 5: Configure Multi-Architecture Images

Step 6: Set Up Authentication

Step 7: Build Images

Step 8: Configure Multi-Module Projects

Step 9: Optimize Build Performance

Requirements

See Also