Fix installation of local plugins

bin/installLocalPlugins.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+set -euo pipefail
+IFS=$'\n\t'
+
+trim() {
+    local var="$*"
+    # remove leading whitespace characters
+    var="${var#"${var%%[![:space:]]*}"}"
+    # remove trailing whitespace characters
+    var="${var%"${var##*[![:space:]]}"}"
+    printf '%s' "$var"
+}
+
+# Move to the Etherpad base directory.
+MY_DIR=$(cd "${0%/*}" && pwd -P) || exit 1
+cd "${MY_DIR}/.." || exit 1
+
+# Source constants and useful functions
+. bin/functions.sh
+
+PNPM_OPTIONS=
+if [ ! -z "${NODE_ENV-}"  ]; then
+  if [ "$NODE_ENV" == 'production' ]; then
+    PNPM_OPTIONS='--prod'
+  fi
+fi
+
+if [ ! -z "${ETHERPAD_LOCAL_PLUGINS_ENV-}"  ]; then
+  if [ "$ETHERPAD_LOCAL_PLUGINS_ENV" == 'production' ]; then
+    PNPM_OPTIONS='--prod'
+  elif [ "$ETHERPAD_LOCAL_PLUGINS_ENV" == 'development' ]; then
+    PNPM_OPTIONS='-D'
+  fi
+fi
+
+if [ ! -z "${ETHERPAD_LOCAL_PLUGINS}" ]; then
+  readarray -d ' ' plugins <<< "${ETHERPAD_LOCAL_PLUGINS}"
+  for plugin in "${plugins[@]}"; do
+    plugin=$(trim "$plugin")
+    if [ -d "local_plugins/${plugin}" ]; then
+      echo "Installing plugin: '${plugin}'"
+      pnpm install -w ${PNPM_OPTIONS:-} "local_plugins/${plugin}/"
+    else
+      ( echo "Error. Directory 'local_plugins/${plugin}' for local plugin " \
+             "'${plugin}' missing" >&2 )
+      exit 1
+    fi
+  done
+else
+  echo 'No local plugings to install.'
+fi