Create publish.yml

Add github action workflow for automatically publish to npm

Author: MatthewPattell

.github/workflows/publish.yml

@@ -0,0 +1,46 @@
+name: Build & Publish
+
+on:
+  push:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      
+      - run: echo "//npm.pkg.github.com/:_authToken=${{ secrets.GITHUB_TOKEN }}" > ~/.npmrc
+      
+      - name: Check if package.json version has been updated
+        id: check
+        uses: EndBug/version-check@v1
+
+      - name: Use Node.js
+        uses: actions/setup-node@v1
+        with:
+          node-version: 14.2
+        if: steps.check.outputs.changed == 'true'
+        
+      - name: Get npm package version
+        id: package-version
+        uses: Saionaro/extract-package-version@v1.1.1
+        if: steps.check.outputs.changed == 'true'
+
+      - name: Create Release
+        id: create_release
+        uses: actions/create-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ steps.package-version.outputs.version}}
+          release_name: v${{ steps.package-version.outputs.version}}
+          draft: false
+          prerelease: false
+        if: steps.check.outputs.changed == 'true'
+
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.GITHUB_TOKEN}}
+        if: steps.check.outputs.changed == 'true'