initial hook restricting author merges

Author: Thomas Osowski

pre-receive-hooks/restrict-author-gui-merges.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+#
+# This hook restricts changes on the default branch to those made with the GUI Pull Request Merge button, or the Pull Request Merge API.
+#
+DEFAULT_BRANCH=$(git symbolic-ref HEAD)
+while read -r oldrev newrev refname; do
+  if [[ "${refname}" != "${DEFAULT_BRANCH:=refs/heads/master}" ]]; then
+    exit 0
+  else
+    if [[ "${GITHUB_VIA}" != 'pull request merge button' && \
+          "${GITHUB_VIA}" != 'pull request merge api' ]]; then
+      echo "Changes to the default branch must be made by Pull Request. Direct pushes, edits, or merges are not allowed."
+      exit 1
+    else
+      AUTHOR_COUNT=$(git log ${DEFAULT_BRANCH}..${newrev} --author="${GITHUB_USER_LOGIN}" --format='%an %cn' | wc -l)
+      echo "Found ${AUTHOR_COUNT} commits"
+      echo "$oldrev"
+      echo "$GITHUB_USER_LOGIN"
+      if (( ${AUTHOR_COUNT} == 0 )); then
+        # No commits containing the current author
+        exit 0
+      else
+        echo "Merging restricted on this branch. Author of commits cannot merge." 
+        echo "Found the following commits by author ${GITHUB_USER_LOGIN}"
+        echo -e $(git log ${DEFAULT_BRANCH}..${newrev} --author="${GITHUB_USER_LOGIN}")
+        # --format='%an %h'
+        exit 1
+      fi
+    fi
+  fi
+done