added github workflow

.github/workflows/npm-publish.yml

@@ -0,0 +1,47 @@
+# This workflow will run tests using node and then publish a package to GitHub Packages when a release is created
+# For more information see: https://help.github.com/actions/language-and-framework-guides/publishing-nodejs-packages
+
+name: Node.js Package
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  publish-npm:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      # Setup .npmrc file to publish to GitHub Packages
+      - uses: actions/setup-node@v1
+        with:
+          node-version: 12
+          registry-url: https://registry.npmjs.org/
+          # Defaults to the user or organization that owns the workflow file
+          scope: '@watergis'
+      - run: npm ci
+      - run: npm test
+      - run: npm run build
+      - run: npm publish --access public
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.npm_token}}
+
+  publish-gpr:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      # Setup .npmrc file to publish to GitHub Packages
+      - uses: actions/setup-node@v1
+        with:
+          node-version: 12
+          registry-url: https://npm.pkg.github.com/
+          # Defaults to the user or organization that owns the workflow file
+          scope: '@watergis'
+      - run: npm ci
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.GITHUB_TOKEN}}
+      - run: npm test
+      - run: npm run build
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.GITHUB_TOKEN}}

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2020 Jin IGARASHI
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,4 +1,7 @@
 # terrain-rgb
+![](https://github.com/watergis/terrain-rgb/workflows/Node.js%20Package/badge.svg)
+![GitHub](https://img.shields.io/github/license/watergis/terrain-rgb)
+
 This module is to get elevation from terrain RGB tilesets by longitude and latitude.
 
 ## Install

package.json

@@ -9,6 +9,9 @@
     "dist",
     "es6"
   ],
+  "publishConfig": {
+    "registry": "https://npm.pkg.github.com/"
+  },
   "scripts": {
     "test": "jest",
     "build": "npm run build:cjs && npm run build:esm",