ci(markdownlint): add Markdown linting (#735)

Author: Michael Buchar

.github/workflows/ci.yml

@@ -124,6 +124,20 @@ jobs:
           npm install jsonlint --global
           ./run-tests.sh --check-jsonlint
 
+  lint-markdownlint:
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node
+        uses: actions/setup-node@v4
+
+      - name: Lint Markdown files
+        run: |
+          npm install markdownlint-cli2 --global
+          ./run-tests.sh --check-markdownlint
+
   format-shfmt:
     runs-on: ubuntu-24.04
     steps:

.markdownlint.yaml

@@ -0,0 +1,4 @@
+# Allow prompt dollar sign in console examples without showing output
+MD014: false
+# Allow multiple headings with same content (for different releases)
+MD024: false

CHANGELOG.md

@@ -1,7 +1,7 @@
 # Contributing
 
-Bug reports, issues, feature requests, and other contributions are welcome. If you find
-a demonstrable problem that is caused by the REANA code, please:
+Bug reports, issues, feature requests, and other contributions are welcome.
+If you find a demonstrable problem that is caused by the REANA code, please:
 
 1. Search for [already reported problems](https://github.com/reanahub/reana-server/issues).
 2. Check if the issue has been fixed or is still reproducible on the

CONTRIBUTING.md

@@ -10,8 +10,8 @@
 ## About
 
 REANA-Server is a component of the [REANA](http://www.reana.io/) reusable and
-reproducible research data analysis platform. It implements the API Server that takes and
-performs REST API calls issued by REANA clients.
+reproducible research data analysis platform. It implements the API Server
+that takes and performs REST API calls issued by REANA clients.
 
 ## Features
 

README.md

@@ -1,3 +1,6 @@
+<!-- markdownlint-disable MD041 -->
+<!-- markdownlint-disable MD033 -->
+
 ```{include} ../README.md
 :end-before: "## About"
 ```

docs/index.md

@@ -131,6 +131,10 @@ check_dockerfile() {
     docker run -i --rm docker.io/hadolint/hadolint:v2.12.0 <Dockerfile
 }
 
+check_markdownlint() {
+    markdownlint-cli2 "**/*.md"
+}
+
 check_docker_build() {
     docker build -t docker.io/reanahub/reana-server .
 }
@@ -154,6 +158,7 @@ check_all() {
     check_jsonlint
     check_yamllint
     check_shfmt
+    check_markdownlint
 }
 
 if [ $# -eq 0 ]; then
@@ -178,5 +183,6 @@ case $arg in
 --check-jsonlint) check_jsonlint ;;
 --check-yamllint) check_yamllint ;;
 --check-shfmt) check_shfmt ;;
+--check-markdownlint) check_markdownlint ;;
 *) echo "[ERROR] Invalid argument '$arg'. Exiting." && exit 1 ;;
 esac