chore: enable npm @next tag version release (#1122)

**Background**
So far in npm we have stable versions, such as `1.0.0-rc.3, 1.0.0-rc.4, 1.0.0-rc.5`.
Now, we decided to release intermediate versions on demand as a preview with `@next` tag,
that would look like: `0.0.0-{hash}`

**How to install it**
To get the last published version under the 'next' tag,
 you need to append `@next` as below:
```js
npm install @ui5/webcomponents@next
```
Without the tag, as you usually install dependencies,
you get the latest released and stable version
```js
npm install @ui5/webcomponents
```

.github/actions/pre-release.js

@@ -0,0 +1,70 @@
+const fs = require("fs");
+const { promisify } = require("util");
+const readFileAsync = promisify(fs.readFile);
+const writeFileAsync = promisify(fs.writeFile);
+const child_process = require("child_process");
+const glob = require("glob-promise");
+const execSync = child_process.execSync;
+const gitRev = execSync("git rev-parse HEAD").toString();
+
+const PACKAGES = {};
+const NPM_ORG = "@ui5/webcomponents";
+const OTP = process.argv[2];
+
+const run = async () => {
+	const FILES = await glob("**/packages/**/package.json", { 
+		"ignore": ["**/node_modules/**/*.*", "**/dist/**/*.*", "**/playground/**/*.*"]
+	});
+
+	// Step 1: process package.json files
+	const pkgs = await Promise.all(FILES.map(processPackageJSON));
+
+	// Step 2: update package.json files
+	await Promise.all(pkgs.map(updatePackageJSON));
+
+	// Step 3: publish each package to npm
+	pkgs.forEach(publishPackage);
+};
+
+const processPackageJSON = async file => {
+	const folder = file.split("package.json")[0];
+	const fileRead = await readFileAsync(file);
+	const fileContent = JSON.parse(fileRead.toString());
+	const name = fileContent.name;
+
+	const version = `0.0.0-${gitRev.slice(0,9,)}`;
+
+	PACKAGES[name] = { name, file, fileContent, version, folder };
+	return PACKAGES[name];
+};
+
+const updatePackageJSON = async pkg => {
+	const file = pkg.file;
+	const fileContent = pkg.fileContent;
+	const dependencies = fileContent.dependencies;
+	const devDependencies = fileContent.devDependencies;
+
+	fileContent.version = pkg.version;
+	dependencies && getDependencies(dependencies).forEach(dep => {
+		fileContent.dependencies[dep] = PACKAGES[dep].version;
+	});
+	devDependencies && getDependencies(devDependencies).forEach(dep => {
+		fileContent.devDependencies[dep] = PACKAGES[dep].version;
+	});
+
+	return writeFileAsync(file, JSON.stringify(fileContent, null, "  "));
+};
+
+const getDependencies = (dependencies) => {
+	return Object.keys(dependencies).filter(dep => dep.startsWith(NPM_ORG));
+};
+
+const publishPackage = pkg => {
+	console.info(`Publish ${pkg.name}: ${pkg.version} ...`); // eslint-disable-line
+	const OTP_PARAM = OTP ? `--otp=${OTP}` : ``;
+	execSync(`yarn publish ${pkg.folder} --tag=next --new-version=${pkg.version} ${OTP_PARAM}`);
+};
+
+run().catch(error => {
+	console.error("Release of @next version failed", error); // eslint-disable-line
+});

.github/workflows/publish.yaml

@@ -0,0 +1,35 @@
+name: Publish
+
+on:
+  push:
+    branches:
+      - master
+jobs:
+  build:
+    if: "contains(github.event.head_commit.message, '#prerelease')"
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+    - uses: actions/setup-node@v1
+      with:
+        node-version: 12
+
+    - name: Install
+      run: yarn
+
+    - name: Build
+      run: yarn build
+
+    - name: Auth
+      run: npm config set //registry.npmjs.org/:_authToken=$NPM_AUTH_TOKEN
+      env:
+        NPM_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+
+    - name: Publish to npm
+      env:
+        NPM_USERNAME: ${{ secrets.NPM_USERNAME }}
+        NPM_EMAIL: ${{ secrets.NPM_EMAIL }}
+        NPM_AUTH_TOKEN: ${{ secrets.NPM_AUTH_TOKEN }}
+      run: |
+        node ./.github/actions/pre-release.js

package.json

@@ -44,12 +44,14 @@
     "test": "npm-run-all --sequential test:base test:main test:fiori",
     "lint": "wsrun --exclude-missing lint",
     "link-all": "wsrun link",
-    "unlink-all": "wsrun unlink"
+    "unlink-all": "wsrun unlink",
+    "prerelease": "node ./.github/actions/pre-release.js"
   },
   "devDependencies": {
-    "nps": "^5.9.8",
     "cross-env": "^5.2.0",
+    "glob-promise": "^3.4.0",
     "npm-run-all": "^4.1.3",
+    "nps": "^5.9.8",
     "rimraf": "^2.6.2",
     "wsrun": "^3.6.4"
   },

yarn.lock

@@ -693,7 +693,7 @@
   resolved "https://registry.yarnpkg.com/@types/events/-/events-3.0.0.tgz#2862f3f58a9a7f7c3e78d79f130dd4d71c25c2a7"
   integrity sha512-EaObqwIvayI5a8dCzhFrjKzVwKLxjoG9T6Ppd5CEo07LRKfQ8Yokw54r5+Wq7FaBQ+yXRvQAYPrHwya1/UFt9g==
 
-"@types/glob@^7.1.1":
+"@types/glob@*", "@types/glob@^7.1.1":
   version "7.1.1"
   resolved "https://registry.yarnpkg.com/@types/glob/-/glob-7.1.1.tgz#aa59a1c6e3fbc421e07ccd31a944c30eba521575"
   integrity sha512-1Bh06cbWJUHMC97acuD6UMG29nMt0Aqz1vF3guLfG+kHHJhy3AyohZFFxYk2f7Q1SQIrNwvncxAE0N/9s70F2w==
@@ -3578,6 +3578,13 @@ glob-parent@^5.0.0, glob-parent@~5.1.0:
   dependencies:
     is-glob "^4.0.1"
 
+glob-promise@^3.4.0:
+  version "3.4.0"
+  resolved "https://registry.npmjs.org/glob-promise/-/glob-promise-3.4.0.tgz#b6b8f084504216f702dc2ce8c9bc9ac8866fdb20"
+  integrity sha512-q08RJ6O+eJn+dVanerAndJwIcumgbDdYiUT7zFQl3Wm1xD6fBKtah7H8ZJChj4wP+8C+QfeVy8xautR7rdmKEw==
+  dependencies:
+    "@types/glob" "*"
+
 glob-to-regexp@^0.3.0:
   version "0.3.0"
   resolved "https://registry.yarnpkg.com/glob-to-regexp/-/glob-to-regexp-0.3.0.tgz#8c5a1494d2066c570cc3bfe4496175acc4d502ab"