pkgdown workflow fails to deploy gh pages

Question

I setup for my R package repository a pkgdown workflow.
The .github/workflows/pkgdown.yaml file:

on:
  push:
    branches: [main, master]
  release:
    types: [published]
  workflow_dispatch:

name: pkgdown

jobs:
  pkgdown:
    runs-on: ubuntu-latest
    env:
      GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
    steps:
      - uses: actions/checkout@v2

      - uses: r-lib/actions/setup-pandoc@v1

      - uses: r-lib/actions/setup-r@v1
        with:
          use-public-rspm: true

      - uses: r-lib/actions/setup-r-dependencies@v1
        with:
          extra-packages: pkgdown
          needs: website

      - name: Deploy package
        if: contains(env.isPush, 'true')
        run: |
          git config --local user.email "[email protected]"
          git config --local user.name "GitHub Actions"
          Rscript -e 'pkgdown::deploy_to_branch(new_process = FALSE)'

The pkgdown workflow works fine, but it fails to update the GitHub pages.
I setup the gh-pages branch as explained in the GitHub documentation, so the workflow pages-build-deployment is present, but when I push on main branch it doesn't run.

Answer 1

I realized the problem was in the if: contains(env.isPush, 'true') line. The condition is never true nor false, since there is no attribute isPush under env, hence the lines

        run: |
          git config --local user.email "[email protected]"
          git config --local user.name "GitHub Actions"
          Rscript -e 'pkgdown::deploy_to_branch(new_process = FALSE)'

were never executed.

To solve the problem, either modify the env part:

    env:
      GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
      isPush: ${{ github.event_name == 'push' }}

or remove the if condition before the run command.