GitHub Actions for ML

name: ML Training Pipeline
on:
  push:
    branches:
      - main
    paths:
      - 'src/train.py'
      - 'data/raw/**'
  pull_request:
    branches:
      - main
  schedule:
    - cron: '0 2 * * MON'
jobs:
  train-and-register:
    runs-on: ubuntu-latest
    env:
      MLFLOW_TRACKING_URI: https://mlflow.example.com
      MLFLOW_TRACKING_USERNAME: ${{ secrets.MLFLOW_USER }}
      MLFLOW_TRACKING_PASSWORD: ${{ secrets.MLFLOW_PASSWORD }}
    steps:
      - uses: actions/checkout@v4
      - uses: iterative/setup-dvc@v1
      - name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: '3.11'
          cache: 'pip'
      - name: Pull data with DVC
        run: |
          dvc remote add -d myremote s3://my-bucket/dvc-storage
          dvc pull
      - name: Install dependencies
        run: |
          pip install --upgrade pip
          pip install -r requirements.txt
      - name: Run training
        run: |
          python src/train.py \
            --epochs 50 \
            --batch-size 32 \
            --log-mlflow
        env:
          PYTHONUNBUFFERED: 1
      - name: Register model if metrics pass
        if: success()
        run: |
          python -c "
          import mlflow
          client = mlflow.tracking.MlflowClient()
          best_run = client.search_runs('0', order_by=['metrics.accuracy DESC'])[0]
          if best_run.data.metrics['accuracy'] > 0.88:
            mlflow.register_model(
              model_uri=f'runs:/{best_run.info.run_id}/model',
              name='iris-classifier'
            )
            print('Model registered')
          else:
            print('Accuracy below threshold, skipping registration')
          "
      - name: Push updated model to DVC (optional)
        if: success()
        run: |
          dvc add models/current.pkl
          git add models/current.pkl.dvc
          git config user.email 'ci@example.com'
          git config user.name 'CI Bot'
          git commit -m 'Update model artifact' || echo 'No changes'
          git push
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}