Add Danger-bot

Signed-off-by: Tom Siewert <[email protected]>

.github/workflows/danger.yml

@@ -0,0 +1,37 @@
+---
+name: Dangerbot
+on:
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  danger:
+    name: Danger
+    runs-on: self-hosted
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Setup Ruby 3.0
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '3.0'
+
+      - name: Configure cache
+        uses: actions/cache@v1
+        with:
+          path: vendor/bundle
+          key: ${{ runner.os }}-gems-${{ hashFiles('Gemfile') }}
+          restore-keys: |
+            ${{ runner.os }}-gems-
+
+      - name: Run Danger
+        uses: MeilCli/danger-action@v5
+        with:
+          plugins_file: 'Gemfile'
+          install_path: 'vendor/bundle'
+          danger_file: 'Dangerfile'
+          danger_id: 'danger-pr'
+        env:
+          DANGER_GITHUB_API_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Dangerfile

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+# -*- mode: ruby -*- vim: set syntax=ruby
+# frozen_string_literal: true
+
+if git.commits.any? { |c| c.message =~ /^Merge branch/ }
+  fail('Please rebase to get rid of the merge commits in this PR!')
+  message "For more information, please see [man git-rebase](https://git-scm.com/docs/git-rebase)."
+end
+
+if !git.modified_files.include?("CHANGELOG.md") && !has_app_changes
+  fail("Please include a CHANGELOG entry. \nYou can find it at [CHANGELOG.md](https://github.com/hetznercloud/ansible-ipxe-ca/blob/main/CHANGELOG.md).")
+  message "Note, we use [changelogger](https://github.com/MarkusFreitag/changelogger) as changelog tooling."
+end

Gemfile

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+# frozen_string_literal: true
+
+source 'https://rubygems.org'
+
+gem 'danger'