Flutter CI/CD Using GitHub Actions — Android & Web Deployment from Zero to Release

In today’s fast-paced tech environment, continuous integration and continuous delivery (CI/CD) are essential for shipping software efficiently. This article provides a comprehensive guide to setting up a CI/CD pipeline for Flutter applications using GitHub Actions, covering Android and Web deployments.

Initial Project Setup

Start by creating a new Flutter project and initializing Git:

• flutter create my_project
• cd my_project
• git init
• git remote add origin https://github.com/your-user/flutter-cicd.git
• git push -u origin master
• mkdir -p .github/workflows

Android Build Workflow

Create an Android release workflow file .github/workflows/android-release.yml:

name: Android Release

on:
  push:
    branches: [ "master" ]
  pull_request:
    branches: [ "master" ]
  workflow_dispatch:

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: actions/setup-java@v3
        with:
          distribution: 'zulu'
          java-version: '12.x'
          cache: 'gradle'
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: '3.0.0'
          channel: 'stable'
          cache: true
      - name: Get dependencies
        run: flutter pub get
      - name: Build AAB
        run: flutter build appbundle

Optimize build time by caching Gradle dependencies. This improves build performance.

Android App Signing (Secure)

Securely sign your Android app by generating a keystore and storing it as a GitHub secret:

• Generate keystore: keytool -genkey -v -keystore upload-keystore.jks -keyalg RSA -keysize 2048 -validity 10000 -alias upload
• Encode keystore: base64 upload-keystore.jks > keystore.txt
• Add secrets to GitHub: KEYSTORE_BASE64, STORE_PASSWORD, KEY_PASSWORD, KEY_ALIAS

Decode the keystore in your workflow:

- name: Decode keystore
  id: android_keystore
  uses: timheuer/base64-to-file@v1.0.3
  with:
    fileName: upload-keystore.jks
    encodedString: $

Deploy to Google Play (Alpha/Internal)

Configure a service account in Google Cloud and enable the Google Play Developer API. Add the JSON key as a secret PLAYSTORE_ACCOUNT_KEY.

- name: Release to Play Store
  uses: r0adkll/upload-google-play@v1
  with:
    serviceAccountJsonPlainText: $
    packageName: com.example.app
    releaseFiles: app-release.aab
    track: alpha
    status: completed

Deploy Flutter Web to GitHub Pages

Create a web release workflow file .github/workflows/web-release.yml:

name: Web Release

on:
  push:
    branches: [ "master" ]
  workflow_dispatch:

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: "3.0.0"
          channel: 'stable'
          cache: true
      - run: flutter pub get
      - run: flutter build web --release
      - uses: actions/upload-artifact@v2
        with:
          name: web-release
          path: build/web

deploy:
  needs: build
  runs-on: ubuntu-latest
  steps:
    - uses: actions/download-artifact@v2
      with:
        name: web-release
    - uses: peaceiris/actions-gh-pages@v3
      with:
        github_token: $
        publish_dir: ./build/web

Set your repository to serve GitHub Pages from the gh-pages branch.

README.md Badge Integration

Integrate badges into your README.md to showcase your CI/CD status:

![Android Build](https://github.com/<your-username>/<repo-name>/actions/workflows/android-release.yml/badge.svg)
![Web Build](https://github.com/<your-username>/<repo-name>/actions/workflows/web-release.yml/badge.svg)

This article provides a foundational understanding of automating Flutter deployments using GitHub Actions. Automating your CI/CD process improves development velocity and ensures consistent releases.