ci: add publish phase

Author: nodkz

.github/workflows/nodejs.yml

@@ -10,22 +10,44 @@ on:
     branches: [master]
 
 jobs:
-  build:
+  tests:
     runs-on: ubuntu-latest
-
     strategy:
       matrix:
         node-version: [10.x, 12.x]
-
     steps:
       - uses: actions/checkout@v2
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v1
         with:
           node-version: ${{ matrix.node-version }}
-      - run: yarn
-      - run: yarn lint
-      - run: yarn test
+      - name: Install node_modules
+        run: yarn
+      - name: Lint & tscheck
+        run: yarn lint
+      - name: Tests
+        run: yarn test
         env:
           CI: true
-      - run: yarn build --if-present
+      - name: Build
+        run: yarn build
+
+  publish:
+    if: github.ref == 'refs/heads/master'
+    needs: [tests]
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Use Node.js 12
+        uses: actions/setup-node@v1
+        with:
+          node-version: 12.x
+      - name: Install node_modules
+        run: yarn install
+      - name: Build
+        run: yarn build
+      - name: Semantic Release (publish to npm)
+        run: yarn semantic-release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          NPM_TOKEN: ${{ secrets.NPM_TOKEN }}