cache node_modules in github workflow

main.yaml

name: Caching npm packages

on: push

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2

    - name: Cache node modules
      id: cache-nodemodules
      uses: actions/cache@v2
      env:
        cache-name: cache-node-modules
      with:
        # caching node_modules
        path: node_modules
        key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('**/package-lock.json') }}
        restore-keys: |
          ${{ runner.os }}-build-${{ env.cache-name }}-
          ${{ runner.os }}-build-
          ${{ runner.os }}-

    - name: Install Dependencies
      if: steps.cache-nodemodules.outputs.cache-hit != 'true'
      run: npm ci

    - name: Build
      run: npm build

The example works well if the primary key has a cache hit and npm ci is skipped. I would remove restore-keys though. Running npm ci will remove any node_modules folder. If there is a cache entry that matches restore-keys but not key, GitHub will restore it, but then cache-hit will be false and npm ci will immediately delete the restored cache before installing dependencies from scratch. A minor thing but will save some redundant work.