Add GitHub Action CI

.github/workflows/ci.yml

@@ -0,0 +1,63 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - "master"
+  pull_request:
+
+jobs:
+  examples_build_and_test:
+    strategy:
+      matrix:
+        example:
+          [
+            web-chat,
+            eth-pm,
+            eth-pm-wallet-encryption,
+            relay-reactjs-chat,
+            store-reactjs-chat,
+            relay-angular-chat,
+          ]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Install NodeJS
+        uses: actions/setup-node@v2
+        with:
+          node-version: "16"
+
+      - name: Check if `yarn` or `npm` is used.
+        id: use-yarn
+        shell: bash
+        run: echo "::set-output name=lockfile::$(ls yarn.lock 2> /dev/null)"
+        working-directory: examples/${{ matrix.example }}
+
+      - name: (npm) Cache npm cache
+        if: steps.use-yarn.outputs.lockfile != 'yarn.lock'
+        uses: actions/cache@v2
+        with:
+          path: ~/.npm
+          key: examples-node-v1-${{ hashFiles('**/package-lock.json') }}
+
+      - name: (npm) ${{ matrix.example }} install using npm i
+        if: steps.use-yarn.outputs.lockfile != 'yarn.lock'
+        run: npm install
+        working-directory: examples/${{ matrix.example }}
+
+      - name: (npm) ${{ matrix.example }} test
+        if: steps.use-yarn.outputs.lockfile != 'yarn.lock'
+        run: npm run test
+        working-directory: examples/${{ matrix.example }}
+
+      - name: (yarn) ${{ matrix.example }} install using yarn
+        if: steps.use-yarn.outputs.lockfile == 'yarn.lock'
+        run: yarn install --frozen-lockfile
+        working-directory: examples/${{ matrix.example }}
+
+      - name: (yarn) ${{ matrix.example }} test
+        if: steps.use-yarn.outputs.lockfile == 'yarn.lock'
+        run: echo "test skipped" # yarn test; tracked with https://github.com/status-im/js-waku/issues/563
+        working-directory: examples/${{ matrix.example }}