Turn on GitHub action for whatsnew (dotnet#22616)

- Add shell script, yml config and package for "what's new" package
- add the NuGet package with the latest tool
- Update the whatsnew.json file to include parameters for automatically updated the index.yml and toc.yml
- Update the TOC so that it has a single rolling list of articles (the action expects that)

.github/workflows/dependencies/run-dotnet-whatsnew.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+set -e
+
+# This script runs the .NET CLI, invoking the what's new global tool
+#     $1 is the <github.repository_owner>
+#     $2 is the <github.repository>
+#     $3 is the savedir
+
+declare -r STARTDATE=$(date "+%F" -d "$(date +'%Y-%m-01') -1 month");
+declare -r ENDDATE=$(date "+%F" -d "$STARTDATE +1 month -1 day");
+
+echo "From $STARTDATE to $ENDDATE"
+
+while getopts o:r:s: option
+do
+case "${option}"
+in
+o) OWNER=${OPTARG};;
+r) REPO=${OPTARG};;
+s) SAVEDIR=${OPTARG};;
+esac
+done
+
+dotnet whatsnew \
+    --owner $OWNER \
+    --repo $REPO \
+    --startdate $STARTDATE \
+    --enddate $ENDDATE \
+    --savedir $SAVEDIR

.github/workflows/whats-new.yml

@@ -0,0 +1,66 @@
+# This is a basic workflow to help you get started with Actions
+
+name: 'generate what''s new article'
+
+# Controls when the action will run. 
+on:
+  # Triggers the workflow on push or pull request events but only for the default branch
+  schedule:
+  - cron: '0 0 1 * *' # The first of every month
+  workflow_dispatch:
+    inputs:
+      reason:
+        description: 'The reason for running the workflow'
+        required: true
+        default: 'Manual run'
+
+env:
+  DOTNET_VERSION: '5.0.301' # set this to the dot net version to use
+  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+# A workflow run is made up of one or more jobs that can run sequentially or in parallel
+jobs:
+  # This workflow contains a single job called "create-what-is-new"
+  create-what-is-new:
+    # The type of runner that the job will run on
+    runs-on: ubuntu-latest
+
+    # Steps represent a sequence of tasks that will be executed as part of the job
+    steps:
+      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+      - uses: actions/checkout@v2
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: ${{ env.DOTNET_VERSION }}
+
+      # Runs a single command using the runners shell
+      - name: 'Print manual run reason'
+        if: ${{ github.event_name == 'workflow_dispatch' }}
+        run: |
+          echo 'Reason: ${{ github.event.inputs.reason }}'
+
+      # Print dotnet info
+      - name: Display .NET info
+        run: dotnet --info
+
+      # Install dotnet-whatsnew global tool
+      - name: Install dotnet-whatsnew tool
+        run: |
+          dotnet tool install --global --add-source ./.github/workflows/dependencies/ dotnet-whatsnew
+
+      # Run dotnet-whatsnew tool
+      - name: Generate what's new
+        id: dotnet-whatsnew
+        env:
+          GitHubKey: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          ./.github/workflows/dependencies/run-dotnet-whatsnew.sh -o dotnet -r AspNetCore.Docs -s './aspnetcore/whats-new'
+
+      # Create the PR for the new article
+      - name: create-pull-request
+        uses: peter-evans/[email protected]
+        with:
+          title: 'What''s new article'
+          commit-message: 'Bot 🤖 generated "What''s new article"'
+          body: 'Automated creation of What''s new article.'

.whatsnew.json

@@ -5,6 +5,13 @@
   "docLinkSettings": {
     "linkFormat": "xref"
   },
+  "navigationOptions": {
+    "maximumNumberOfArticles": 6,
+    "tocParentNode": "What's new",
+    "repoTocFolder": "aspnetcore/whats-new",
+    "indexParentNode": "Find ASP.NET Core docs updates",
+    "repoIndexFolder": "aspnetcore/whats-new"
+  },
   "inclusionCriteria": {
     "additionalMicrosoftOrgs": [
       "ASP.NET"

aspnetcore/whats-new/toc.yml

@@ -1,23 +1,17 @@
+items:
 - name: What's new
   href: index.yml
   expanded: true
   items:
-    - name: 2021
-      expanded: true
-      items:
-      - name: May
-        href: 2021-05.md
-      - name: April
-        href: 2021-04-01.md
-      - name: March
-        href: 2021-03.md
-      - name: February
-        href: 2021-02.md
-      - name: January
-        href: 2021-01.md
-    - name: 2020
-      expanded: true
-      items:
-      - name: December
-        href: 2020-12.md
-
+    - name: May 2021
+      href: 2021-05.md
+    - name: April 2021
+      href: 2021-04-01.md
+    - name: March 2021
+      href: 2021-03.md
+    - name: February 2021
+      href: 2021-02.md
+    - name: January 2021
+      href: 2021-01.md
+    - name: December 2021
+      href: 2020-12.md