Flutter #41: GitHub Actions CI/CD

Selamat pagi! Hari ini kita masuk ke topik yang sering jadi tanda tanya bagi developer: CI/CD dengan GitHub Actions. Kalau kamu pernah manual build APK, upload ke Play Store, atau cek test satu-satu di lokal — artikel ini bakal bantu otomatisasiin semuanya.

GitHub Actions gratis untuk repo publik (dan cukup generous untuk private). Kita cuma butuh file YAML di .github/workflows/, dan setiap push ke main atau pull request bakal jalanin test, build, bahkan deploy otomatis.

Kenapa Perlu CI/CD?

Bayangin skenario ini:

Kamu push ke main jam 2 pagi.
GitHub Actions jalanin flutter test — kalau gagal, kamu dapet notifikasi email/Slack.
Kalau test lolos, build APK dan AAB otomatis.
Artefak (APK/AAB) tersimpan sebagai artifact — bisa di-download tim QA.
(Opsional) Deploy ke Firebase App Distribution / Play Store Internal Testing.

Semua tanpa nyentuh terminal lokal. Ini yang namanya continuous integration dan continuous delivery.

Struktur Workflow GitHub Actions

File workflow simpan di .github/workflows/ci.yml. Format dasar:

name: CI/CD Flutter

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  test:
    name: Run Tests
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: '3.24.0'
          channel: 'stable'
      - run: flutter pub get
      - run: flutter test --coverage
      - uses: actions/upload-artifact@v4
        with:
          name: coverage
          path: coverage/lcov.info

  build:
    name: Build APK & AAB
    needs: test
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: '3.24.0'
          channel: 'stable'
      - run: flutter pub get
      - run: flutter build apk --release
      - run: flutter build appbundle --release
      - uses: actions/upload-artifact@v4
        with:
          name: release-apk
          path: build/app/outputs/flutter-apk/app-release.apk
      - uses: actions/upload-artifact@v4
        with:
          name: release-aab
          path: build/app/outputs/bundle/release/app-release.aab

Penjelasan singkat:

on: trigger kapan workflow jalan (push ke main, PR ke main).
jobs: daftar job yang dijalanin. test jalan dulu, build butuh test lolos (needs: test).
runs-on: ubuntu-latest: pakai runner Linux gratis GitHub.
subosito/flutter-action@v2: action resmi setup Flutter (cache SDK, cepet).
actions/upload-artifact@v4: simpan file hasil build biar bisa di-download dari UI GitHub.

Contoh 1: Workflow Lengkap dengan Code Coverage & Lint

Kita tambah flutter analyze dan upload coverage ke Codecov (gratis untuk open source).

# .github/workflows/ci.yml
name: CI/CD Flutter

on:
  push:
    branches: [main, develop]
  pull_request:
    branches: [main, develop]

env:
  FLUTTER_VERSION: '3.24.0'

jobs:
  analyze:
    name: Analyze & Format
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: $
          channel: 'stable'
      - run: flutter pub get
      - run: dart format --set-exit-if-changed .
      - run: flutter analyze --fatal-infos

  test:
    name: Unit & Widget Tests
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: $
          channel: 'stable'
      - run: flutter pub get
      - run: flutter test --coverage
      - name: Upload coverage to Codecov
        uses: codecov/codecov-action@v4
        with:
          files: ./coverage/lcov.info
          fail_ci_if_error: false

  build-android:
    name: Build Android (APK + AAB)
    needs: [analyze, test]
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: $
          channel: 'stable'
      - run: flutter pub get
      - run: flutter build apk --release --split-per-abi
      - run: flutter build appbundle --release
      - uses: actions/upload-artifact@v4
        with:
          name: android-apks
          path: build/app/outputs/flutter-apk/*.apk
      - uses: actions/upload-artifact@v4
        with:
          name: android-aab
          path: build/app/outputs/bundle/release/app-release.aab

  build-ios:
    name: Build iOS (IPA)
    needs: [analyze, test]
    runs-on: macos-latest
    steps:
      - uses: actions/checkout@v4
      - uses: subosito/flutter-action@v2
        with:
          flutter-version: $
          channel: 'stable'
      - run: flutter pub get
      - run: flutter build ipa --release --export-options-plist=ExportOptions.plist
      - uses: actions/upload-artifact@v4
        with:
          name: ios-ipa
          path: build/ios/ipa/*.ipa

Catatan:

build-ios butuh macos-latest runner (macOS runner gratis tapi quota terbatas).
--split-per-abi biar APK jadi 3 file (arm64-v8a, armeabi-v7a, x86_64) — ukuran lebih kecil.
ExportOptions.plist perlu disiapin di repo untuk signing iOS (lihat docs Apple).

Contoh 2: Deploy ke Firebase App Distribution

Supaya QA bisa install APK langsung dari Firebase, tambah step deploy:

# Tambah di job build-android setelah upload-artifact
- name: Deploy to Firebase App Distribution
  uses: wzieba/Firebase-Distribution-Github-Action@v1
  with:
    appId: $
    token: $
    groups: qa-team
    file: build/app/outputs/flutter-apk/app-release.apk

Butuh setup di Firebase Console:

Buat project Firebase → App Distribution.
Dapatkan App ID (format 1:123456789:android:abcdef).
Generate FIREBASE_TOKEN via firebase login:ci di lokal, simpan ke GitHub Secrets (Settings → Secrets → Actions).

Tips & Best Practice

Tips	Kenapa
Cache `pub` cache	`actions/cache@v4` key `pub-$` — cepetin `flutter pub get`
Pin Flutter version	Hindari breaking change pas update Flutter stable
Fail fast	`flutter analyze --fatal-infos` biar warning jadi error di CI
Matrix testing	Test di multiple Flutter version / OS pakai `strategy.matrix`
Separate workflow	Pisah `ci.yml` (test+analyze) dan `release.yml` (build+deploy) — biar PR cepet, release manual

Contoh cache pub:

- uses: actions/cache@v4
  with:
    path: |
      ~/.pub-cache
      $/flutter
    key: flutter-$-$
    restore-keys: |
      flutter-$-

Debugging Workflow Gagal

Cek log di tab Actions — klik job yang merah, expand step yang gagal.
Re-run job — tombol “Re-run jobs” di kanan atas.
SSH ke runner (hanya private repo / enterprise) — pakai mxschmitt/action-tmate@master untuk debug interaktif.
Local act — nektos/act jalanin GitHub Actions di lokal (butuh Docker).

Checklist Sebelum Push

flutter analyze bersih di lokal
flutter test semua lolos
pubspec.lock committed (bukan di .gitignore)
Secrets di GitHub: FIREBASE_TOKEN, FIREBASE_APP_ID, dll
ExportOptions.plist untuk iOS (kalau build iOS)

Kesimpulan

GitHub Actions + Flutter = otomatisasi gratis & powerful. Mulai dari workflow sederhana (test + build APK) sampe pipeline lengkap dengan deploy ke Firebase/Play Store. Kuncinya: mulai kecil, tambah step seiring butuh.

Tips: Kalau repo private, GitHub Actions gratis 2000 menit/bulan. Cukup untuk project pribadi & tim kecil.

Coba sendiri! Buat file .github/workflows/ci.yml, push, dan lihat tab Actions di repo GitHub kamu. Share ke sosial media dan tag @ahsai001 kalau berhasil (atau butuh bantuan debug).

Artikel selanjutnya: Flutter #42 — Build APK/AAB & AppBundle (detail signing, versioning, Play Console).