Git hook to reject commit messages with HTML tags in them

gitea/hooks/deny-html-tags

@@ -0,0 +1,48 @@
+#!/bin/bash -eu
+
+# Reject commits that contain HTML tags in their commit messages.
+# Allow override with a special key phrase in the message.
+
+set -o pipefail
+
+nullsha="0000000000000000000000000000000000000000"
+status=0
+override_msg="override html check"
+
+while read oldref newref refname; do
+    # Skip branch deletions
+    if [ "$newref" = "$nullsha" ]; then
+        continue
+    fi
+
+    # Handle new branches
+    if [ "$oldref" = "$nullsha" ]; then
+        oldref="HEAD"
+    fi
+
+    # Loop through each new commit
+    for commit in $(git rev-list ${oldref}..${newref}); do
+        # Get full commit message
+        msg=$(git log --format=%B -n 1 "$commit")
+
+        # Check for override
+        if echo "$msg" | grep -qi "$override_msg"; then
+            echo "Commit $commit allowed due to override message."
+            continue
+        fi
+
+        # Check for HTML tags
+        if echo "$msg" | grep -qE '</?[a-z][a-z0-9]*[^<>]*>'; then
+            echo "ERROR: Commit $commit contains HTML tags in the message."
+            echo "Message:"
+            echo "----------------------------------------"
+            echo "$msg"
+            echo "----------------------------------------"
+            echo "Please remove the HTML tags or use the override phrase:"
+            echo "\"$override_msg\""
+            status=1
+        fi
+    done
+done
+
+exit $status