ci: warn about incorrect outgoing links (#141)

* feat: detect bad outgoing links

* chore: fix `tput` warnings

* chore: strip trailing whitespace

* fix: incorrect links to Control Plane

* chore: use checkout@v3 instead of v2

.github/workflows/check_cpln_links.yml

@@ -0,0 +1,19 @@
+name: Check Links
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  check_cpln_links:
+    runs-on: ubuntu-latest
+    name: Check Links
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+      - name: Validate outgoing links to Control Plane
+        run: |
+          TERM=xterm-color ./script/check_cpln_links
+        shell: bash

.overcommit.yml

@@ -1,4 +1,7 @@
 PreCommit:
+  ValidateLinks:
+    enabled: true
+    command: ["bash", "./script/check_cpln_links"]
   CommandDocs:
     enabled: true
     command: ["bundle", "exec", "rake", "check_command_docs"]

README.md

@@ -1,4 +1,4 @@
-# The power of Kubernetes with the ease of Heroku! 
+# The power of Kubernetes with the ease of Heroku!
 
 <meta name="author" content="Justin Gordon and Sergey Tarasov">
 <meta name="description" content="Instructions on how to migrate from Heroku to Control Plane and a CLI called cpl to make it easier.">
@@ -12,16 +12,16 @@
 [![Gem](https://badge.fury.io/rb/cpl.svg)](https://badge.fury.io/rb/cpl)
 
 
-Here's a playbook for migrating from [Heroku Flow](https://www.heroku.com/flow) to [Control Plane](https://controlplane.com/shakacode) with our `cpl` gem source code.
+Here's a playbook for migrating from [Heroku Flow](https://www.heroku.com/flow) to [Control Plane](https://shakacode.controlplane.com) with our `cpl` gem source code.
 
 ----
 
 _If you need a free demo account for Control Plane (no CC required), you can contact [Justin Gordon, CEO of ShakaCode](mailto:justin@shakacode.com)._
 
 ---
 
-Be sure to see the [demo app](https://github.com/shakacode/react-webpack-rails-tutorial/tree/master/.controlplane) 
-If you would like to see the simple YAML configuration and setup, 
+Be sure to see the [demo app](https://github.com/shakacode/react-webpack-rails-tutorial/tree/master/.controlplane)
+If you would like to see the simple YAML configuration and setup,
 Also, check [how the `cpl` gem (this project) is used in the Github actions](https://github.com/shakacode/react-webpack-rails-tutorial/blob/master/.github/actions/deploy-to-control-plane/action.yml).
 Here is a brief [video overview](https://www.youtube.com/watch?v=llaQoAV_6Iw).
 
@@ -125,7 +125,7 @@ npm update -g @controlplane/cli
 
 5. Run `cpln image docker-login --org <your-org>` to ensure that you have access to the Control Plane Docker registry.
 
-6. Install Heroku to Control Plane `cpl` CLI as a [Ruby gem](https://rubygems.org/gems/cpl): `gem install cpl`. If you want to hack on the source code, see [CONTRIBUTING.md](CONTRIBUTING.md). 
+6. Install Heroku to Control Plane `cpl` CLI as a [Ruby gem](https://rubygems.org/gems/cpl): `gem install cpl`. If you want to hack on the source code, see [CONTRIBUTING.md](CONTRIBUTING.md).
 
 7. You can use [this Dockerfile](https://github.com/shakacode/react-webpack-rails-tutorial/blob/master/.controlplane/Dockerfile) as an example for your project. Ensure that you have Docker running.
 
@@ -493,7 +493,7 @@ cpl --help
 - See [how the `cpl` gem is used in the Github actions](https://github.com/shakacode/react-webpack-rails-tutorial/blob/master/.github/actions/deploy-to-control-plane/action.yml).
 - Here is a brief [video overview](https://www.youtube.com/watch?v=llaQoAV_6Iw).
 
-## Resources  
+## Resources
 * If you need a free demo account for Control Plane (no CC required), you can contact [Justin Gordon, CEO of ShakaCode](mailto:justin@shakacode.com).
-* [Control Plane Site](https://controlplane.com/shakacode)
+* [Control Plane Site](https://shakacode.controlplane.com)
 * [Join our Slack to Discuss Heroku to Control Plane](https://reactrails.slack.com/join/shared_invite/enQtNjY3NTczMjczNzYxLTlmYjdiZmY3MTVlMzU2YWE0OWM0MzNiZDI0MzdkZGFiZTFkYTFkOGVjODBmOWEyYWQ3MzA2NGE1YWJjNmVlMGE)

script/check_cpln_links

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+
+bad_links=("controlplane.com/shakacode")
+proper_links=("shakacode.controlplane.com")
+
+bold=$(tput bold)
+normal=$(tput sgr0)
+
+exit_status=0
+accumulated_results=""
+seen_bad_links_indexes=()
+
+for ((idx = 0; idx < ${#bad_links[@]}; idx++)); do
+    results=$(git grep \
+        --recursive \
+        --line-number \
+        --fixed-strings \
+        --break \
+        --heading \
+        --color=always -- \
+        "${bad_links[idx]}" \
+        ':!script/check_cpln_links')
+
+    # Line would become really unwieldly if everything was mushed into the
+    # conditional, so let's ignore this check here.
+    # shellcheck disable=SC2181
+    if [ $? -eq 0 ]; then
+        accumulated_results+="$results"
+        seen_bad_links_indexes+=("$idx")
+        exit_status=1
+    fi
+done
+
+if [ "$exit_status" -eq 1 ]; then
+    echo "${bold}[!] Found the following bad links:${normal}"
+    echo ""
+    echo "$accumulated_results"
+    echo ""
+    echo "${bold}[*] Please update accordingly:${normal}"
+    for bad_link_index in "${seen_bad_links_indexes[@]}"; do
+        echo "  ${bad_links[bad_link_index]} -> ${proper_links[bad_link_index]}"
+    done
+fi
+
+exit "$exit_status"