From f980c8db515e74f0c6026e84572a9b412bbdb94f Mon Sep 17 00:00:00 2001
From: Michael Bausor <michaelbausor@google.com>
Date: Mon, 5 Mar 2018 09:14:28 -0800
Subject: [PATCH] Add daemonutils to locate autoloader

---
 Core/bin/google-cloud-batch        | 17 ++++-------
 Core/src/Daemon/DaemonUtils.php    | 46 ++++++++++++++++++++++++++++++
 Debugger/bin/google-cloud-debugger | 17 ++++-------
 3 files changed, 58 insertions(+), 22 deletions(-)
 create mode 100644 Core/src/Daemon/DaemonUtils.php

diff --git a/Core/bin/google-cloud-batch b/Core/bin/google-cloud-batch
index b0114986908b..40ec606a07eb 100755
--- a/Core/bin/google-cloud-batch
+++ b/Core/bin/google-cloud-batch
@@ -18,20 +18,15 @@
 
 namespace Google\Cloud\Core\Batch;
 
-// Load the autoloader
-if (file_exists(__DIR__ . '/../vendor/autoload.php')) {
-    // Called from local git clone.
-    require_once __DIR__ . '/../vendor/autoload.php';
-} elseif (file_exists(__DIR__ . '/../../../autoload.php')) {
-    // Called from google/cloud-core installation.
-    require_once __DIR__ . '/../../../autoload.php';
-} elseif (file_exists(__DIR__ . '/../../../../autoload.php')) {
-    // Called from google/cloud installation.
-    require_once __DIR__ . '/../../../../autoload.php';
-} else {
+use Google\Cloud\Core\Daemon\DaemonUtils;
+
+$autoloader = DaemonUtils::locateAutoloader(__DIR__ . '/..');
+if (is_null($autoloader)) {
     die('No autoloader found');
 }
 
+require_once $autoloader;
+
 function showUsageAndDie()
 {
     die("usage: " . __FILE__ . " [daemon|retry] {id}");
diff --git a/Core/src/Daemon/DaemonUtils.php b/Core/src/Daemon/DaemonUtils.php
new file mode 100644
index 000000000000..dbfdd80c6db1
--- /dev/null
+++ b/Core/src/Daemon/DaemonUtils.php
@@ -0,0 +1,46 @@
+<?php
+/**
+ * Copyright 2018 Google Inc. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+namespace Google\Cloud\Core\Daemon;
+
+/**
+ * Class DaemonUtils contains utility functions to support daemons
+ * @package Google\Cloud\Core\Daemon
+ */
+class DaemonUtils
+{
+    private static $autoloaderCandidates = [
+        '/vendor/autoload.php',     // Git clone of subcomponent
+        '/../vendor/autoload.php',  // Git clone of google-cloud-php
+        '/../../autoload.php',      // Subcomponent installation
+        '/../../../autoload.php',   // google/cloud installation
+    ];
+
+    /**
+     * @param string $subcomponentRoot Path to root of subcomponent for which to locate autoloader
+     * @return string Path to autoloader, or null
+     */
+    public static function locateAutoloader($subcomponentRoot)
+    {
+        foreach (self::$autoloaderCandidates as $candidate) {
+            if (file_exists($subcomponentRoot . $candidate)) {
+                return $subcomponentRoot . $candidate;
+            }
+        }
+        return null;
+    }
+}
diff --git a/Debugger/bin/google-cloud-debugger b/Debugger/bin/google-cloud-debugger
index 2554e3a7d3be..98c956216b02 100755
--- a/Debugger/bin/google-cloud-debugger
+++ b/Debugger/bin/google-cloud-debugger
@@ -18,20 +18,15 @@
 
 namespace Google\Cloud\Debugger;
 
-// Load the autoloader
-if (file_exists(__DIR__ . '/../../../vendor/autoload.php')) {
-    // Called from local git clone.
-    require_once __DIR__ . '/../../../vendor/autoload.php';
-} elseif (file_exists(__DIR__ . '/../../../autoload.php')) {
-    // Called from google/cloud-core installation.
-    require_once __DIR__ . '/../../../autoload.php';
-} elseif (file_exists(__DIR__ . '/../../../../../autoload.php')) {
-    // Called from google/cloud installation.
-    require_once __DIR__ . '/../../../../../autoload.php';
-} else {
+use Google\Cloud\Core\Daemon\DaemonUtils;
+
+$autoloader = DaemonUtils::locateAutoloader(__DIR__ . '/..');
+if (is_null($autoloader)) {
     die('No autoloader found');
 }
 
+require_once $autoloader;
+
 function showUsageAndDie()
 {
     $filename = basename(__FILE__);