functions

#!/usr/bin/env bash
set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x

# git specific implementation
get_latest_commit_user_from_git() {
  local APP="$1"; local REV="$2"

  pushd "$DOKKU_ROOT/$APP" > /dev/null
  COMMIT_AUTHOR=$(git log -n1 "$REV" --pretty="%an <%ae> (%h)" || true)
  [[ -n "$COMMIT_AUTHOR" ]] && echo "$COMMIT_AUTHOR"
}

# example for bzr
get_latest_commit_user_from_bzr() {
  local APP="$1"

  pushd "$DOKKU_ROOT/$APP" > /dev/null
  LATEST_BZR_LOG=$(bzr log -l 1 | grep committer || true)
  [[ -n "$LATEST_BZR_LOG" ]] && COMMIT_AUTHOR=$(echo "$LATEST_BZR_LOG" | sed -r -n "s/committer: (.*)/\1/p" || true)
  [[ -n "$COMMIT_AUTHOR" ]] && echo "$COMMIT_AUTHOR"
}

# wrapper function to be extended to other VCS
get_commit_author_by_rev() {
  local APP="$1"; local REV="$2"

  pushd "$DOKKU_ROOT/$APP" > /dev/null
  if (git log -1 &> /dev/null); then
    get_latest_commit_user_from_git "$APP" "$REV"
  elif (bzr log -l 1 &> /dev/null); then
    get_latest_commit_user_from_bzr "$APP"
  else
    echo "$USER"
  fi
}