# Jenkins Shared Library: Docker Build & Push Steps

This Jenkins shared library provides reusable steps for building and pushing Docker images from your pipelines.

## 📦 Included Steps

| Step          | Description                            |
|---------------|----------------------------------------|
| `dockerBuild` | Builds a Docker image                  |
| `dockerPush`  | Pushes a Docker image to a registry    |

Each step is implemented as a Global Variable, making them directly usable in declarative pipelines.

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## 🧩 How to Set Up in Jenkins

### 1. Push the Library to a Git Repository

Host this repository in a Git server accessible to your Jenkins instance (e.g. GitHub, GitLab, Gitea, etc.).

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### 2. Register the Library in Jenkins

Go to **Manage Jenkins → Configure System → Global Pipeline Libraries**, then click **Add**.

Fill in the following:

- **Name**: `mylib` (or any name you'd like to reference in Jenkinsfiles)
- **Default version**: `main` (or specify a tag/branch)
- **Retrieval method**: Modern SCM
- **Source Code Management**: Git
  - **Project Repository**: `https://your.git.repo/jenkins-shared-library.git`
  - **Credentials**: (only if private)

Click **Save**.

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## ✅ How to Use in Your Jenkinsfile

In any Jenkins pipeline, include the shared library using `@Library` and then call the steps:

```groovy
@Library('mylib') _

pipeline {
    agent any

    environment {
        DOCKER_REGISTRY = 'your.registry.example.com'
        IMAGE_NAME = 'your/image-name'
        IMAGE_TAG = "${DOCKER_REGISTRY}/${IMAGE_NAME}:${params.BUILD_ID}"
    }

    parameters {
        string(name: 'BUILD_ID', defaultValue: 'latest', description: 'Docker image tag')
    }

    stages {
        stage('Build Docker Image') {
            steps {
                dockerBuild(
                    imageName: "${IMAGE_TAG}",
                    dockerfile: "deployments/docker/Dockerfile",
                    context: "deployments/docker"
                )
            }
        }

        stage('Push Docker Image') {
            steps {
                dockerPush(
                    imageName: "${IMAGE_TAG}",
                    registry: "${DOCKER_REGISTRY}",
                    credentialsId: "your-docker-credentials-id"
                )
            }
        }
    }
}