ci: Calculate Node.js version dynamically for the ci matrix (#93)

.github/workflows/node.js.yml

@@ -1,25 +1,40 @@
-# This workflow will do a clean install of node dependencies, build the source code and run tests across different versions of node
-# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
-
 name: Node.js CI
 on: [push, pull_request]
 
 jobs:
-  build:
-
+  # https://thekevinwang.com/2021/09/19/github-actions-dynamic-matrix/
+  prepare_matrix:
     runs-on: ubuntu-latest
+    outputs:
+      versions: ${{ steps.generate-matrix.outputs.versions }}
+    steps:
+    - name: Generate Node.js versions matrix
+      id: generate-matrix
+      run: |
+        current_lts=$(curl -s https://nodejs.org/en/ | grep -E -o 'Download [0-9.]+ LTS' | grep -E -o '([0-9]+)' | head -n 1)
+        previous_lts=$(( current_lts - 2 ))
+        next_lts=$(( current_lts + 2 ))
+        VERSIONS="[$previous_lts, $current_lts, $next_lts]"
+        echo ::set-output name=versions::${VERSIONS}
 
+  build:
+    runs-on: ubuntu-latest
+    needs:
+    - prepare_matrix
     strategy:
       matrix:
-        node-version: [14, 16, 18]
-
+        node-version: ${{ fromJSON(needs.prepare_matrix.outputs.versions) }}
     steps:
-    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # tag=v3
+    - uses: actions/checkout@v3
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@2fddd8803e2f5c9604345a0b591c3020ee971a93 # tag=v3
+      uses: actions/setup-node@v3
       with:
         node-version: ${{ matrix.node-version }}
     - run: |
-        npm ci
-        npm test
-        npm run lint
+        npm i -g npm
+        npm ci || npm install
+      name: Install dev dependencies
+    - run: npm run lint
+      name: Linter
+    - run: npm run test
+      name: Tests