Add publish CI

.github/workflows/publish.yml

@@ -0,0 +1,21 @@
+name: publish to npm
+on:
+  push:
+    tags:
+      - v*
+
+jobs:
+  publish-npm:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v1
+        with:
+          node-version: 12
+          registry-url: https://registry.npmjs.org/
+      - name: Check release validity
+        run: sh scripts/check-release.sh
+      - name: Publish
+        run: npm publish .
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.NPM_TOKEN}}

scripts/check-release.sh

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+# Checking if current tag matches the package version
+current_tag=$(echo $GITHUB_REF | tr -d 'refs/tags/v')
+file_tag=$(grep '"version":' package.json | cut -d ':' -f 2- | tr -d ' ' | tr -d '"' | tr -d ',')
+if [ "$current_tag" != "$file_tag" ]; then
+  echo "Error: the current tag does not match the version in package file(s)."
+  echo "$current_tag vs $file_tag"
+  exit 1
+fi
+
+echo 'OK'
+exit 0