Tutorial: Docker Build & Push

In this tutorial you will build a pipeline that builds a Docker image and pushes it to Docker Hub whenever a version tag is pushed (e.g. v1.2.3).

Time: ~10 minutes Export target: GitHub Actions

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Prerequisites

• A Docker Hub account
• A repository with a Dockerfile at the root
• A Docker Hub access token (create one at hub.docker.com → Account Settings → Security)

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What you'll build

Trigger: tag push matching v*
    │
    ▼
[Release Stage]
  └── docker-release (ubuntu-latest)
        1. Checkout
        2. Docker login
        3. Docker build
        4. Docker push
        5. Notify Slack (optional)

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Step 1 — Store your Docker Hub token

Before building the pipeline, save your Docker Hub token in the credential vault.

1. Go to Settings → Credentials → New Credential
2. Fill in:
   • Label: Docker Hub Token
   • Provider: docker
   • Value: <your Docker Hub access token>
3. Save

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Step 2 — Create the pipeline

1. Open (or create) your project
2. Click New Pipeline → name it docker-release

Step 3 — Configure the trigger

Click Trigger:

• Type: Tag
• Tag patterns: v*

This fires on any tag that starts with v.

Step 4 — Add the Release stage

Add a stage named Release.

Double-click to enter it. Add a job:

• Name: docker-release
• Runs on: ubuntu-latest

Enter the job and add steps:

Step 1 — Checkout

• Type: git / Operation: checkout

Step 2 — Docker login

• Type: docker / Operation: run (or shell_command)
• Script:

  echo "$DOCKER_TOKEN" | docker login -u "$DOCKER_USERNAME" --password-stdin

• Secrets: select Docker Hub Token → it will be injected as DOCKER_TOKEN
• Environment variables: DOCKER_USERNAME = yourdockerhubusername

Step 3 — Docker build

• Type: docker / Operation: build
• Image name: yourusername/my-app
• Tag: ${ { github.ref_name } } (GitHub Actions expression for the tag name)
• Dockerfile: ./Dockerfile

Step 4 — Docker push

• Type: docker / Operation: push
• Image: yourusername/my-app:${ { github.ref_name } }

Step 5 — Also push latest tag (optional)

• Type: shell_command
• Script:

  docker tag yourusername/my-app:${ { github.ref_name } } yourusername/my-app:latest
  docker push yourusername/my-app:latest

Step 5 — Save and export

Click Save then Export → GitHub Actions → Download.

Commit docker-release.yml to .github/workflows/.

Step 6 — Test the pipeline

Push a tag:

git tag v1.0.0
git push origin v1.0.0

GitHub Actions will trigger, build your image, and push yourusername/my-app:v1.0.0 and yourusername/my-app:latest to Docker Hub.

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Add a Slack notification (optional)

At the end of the job, add a notification step to announce the release:

Step — Notify Slack

• Type: notification
• Channel: slack
• Webhook URL: stored as a credential named Slack Webhook
• Message: 🚀 Released yourusername/my-app:${ { github.ref_name } }