Documentation: Introduces a check stage to validate HTML and links

script/docs-verify-docker-image/validate.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+
+set -eu
+
+PATH_TO_SITE="/app/site"
+[ -d "${PATH_TO_SITE}" ]
+
+NUMBER_OF_CPUS="$(grep -c processor /proc/cpuinfo)"
+
+
+echo "=== Checking HTML content..."
+
+# Search for all HTML files except the theme's partials
+# and pipe this to htmlproofer with parallel threads
+# (one htmlproofer per vCPU)
+find "${PATH_TO_SITE}" -type f -not -path "/app/site/theme/*" \
+    -name "*.html" -print0 \
+| xargs -0 -r -P "${NUMBER_OF_CPUS}" -I '{}' \
+  htmlproofer \
+  --check-html \
+  --alt_ignore="/traefik.logo.png/" \
+  --url-ignore "/localhost:/,/127.0.0.1:/,/fonts.gstatic.com/,/.minikube/,/github.com\/containous\/traefik\/*edit*/,/github.com\/containous\/traefik\/$/" \
+  '{}'
+## HTML-proofer options at https://github.com/gjtorikian/html-proofer#configuration
+
+echo "= Documentation checked successfuly."