name: PyTorch & Conda

# see: https://help.github.com/en/actions/reference/events-that-trigger-workflows
on:
  # Trigger the workflow on push or pull request,
  # but only for the master branch
  push:
    branches:
      - master
  pull_request:
    branches:
      - master
# Trigger the workflow on push or pull request
# on: [push, pull_request]

jobs:
  conda:

    runs-on: ${{ matrix.os }}
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu-20.04]
        python-version: [3.7]
        # todo: add nightly versions
        pytorch-version: [1.3, 1.4, 1.5, 1.6]  # , 1.7

    # Timeout: https://stackoverflow.com/a/59076067/4521646
    timeout-minutes: 20
    steps:
    - uses: actions/checkout@v2

    - name: Setup pyTorch
      run: |
        python -c "fname = 'environment.yml' ; req = open(fname).read().replace('torch>=1.3', 'torch=${{ matrix.pytorch-version }}') ; open(fname, 'w').write(req)"
        cat environment.yml

    # TODO: set source for nightly

    - name: Cache conda
      uses: actions/cache@v1
      env:   # Increase this value to reset cache if etc/example-environment.yml has not changed
        CACHE_NUMBER: 0
      with:
        path: ~/conda_pkgs_dir
        key: ${{ runner.os }}-conda-${{ env.CACHE_NUMBER }}-${{ hashFiles('environment.yml') }}

    # https://docs.conda.io/projects/conda/en/4.6.0/_downloads/52a95608c49671267e40c689e0bc00ca/conda-cheatsheet.pdf
    # https://gist.github.com/mwouts/9842452d020c08faf9e84a3bba38a66f
    - name: Setup Miniconda
      uses: goanpeca/setup-miniconda@v1.6.0
      with:
          # auto-update-conda: true
          auto-activate-base: false
          miniconda-version: 4.7.12
          python-version: ${{ matrix.python-version }}
          environment-file: environment.yml
          activate-environment: pl-env
          use-only-tar-bz2: true # IMPORTANT: This needs to be set for caching to work properly!

    - name: Reinstall Horovod if necessary
      if: runner.os != 'windows'
      run: |
        HOROVOD_BUILT=$(python -c "import horovod.torch; horovod.torch.nccl_built(); print('SUCCESS')" || true)
        if [[ $HOROVOD_BUILT != "SUCCESS" ]]; then
          pip uninstall -y horovod
          HOROVOD_BUILD_ARCH_FLAGS="-mfma" pip install --no-cache-dir $(grep "horovod" requirements/extra.txt)
        fi
        horovodrun --check-build
      shell: bash -l {0}

    - name: Cache datasets
      uses: actions/cache@v1
      with:
        path: Datasets # This path is specific to Ubuntu
        # Look to see if there is a cache hit for the corresponding requirements file
        key: pl-dataset

    - name: Tests
      run: |
        conda info
        conda list
        # NOTE: run coverage on tests does not propagare faler status for Win, https://github.com/nedbat/coveragepy/issues/1003
        python -m pytest pytorch_lightning tests -v --junitxml=junit/test-results-${{ runner.os }}-${{ matrix.python-version }}-${{ matrix.requires }}.xml
        # coverage report
      shell: bash -l {0}

    - name: Upload pytest test results
      uses: actions/upload-artifact@master
      with:
        name: pytest-results-${{ runner.os }}-${{ matrix.python-version }}-${{ matrix.requires }}
        path: junit/test-results-${{ runner.os }}-${{ matrix.python-version }}-${{ matrix.requires }}.xml
      # Use always() to always run this step to publish test results when there are test failures
      if: always()