From 271dc266faf55bcef7a15e1b9e006cb9ba020dc3 Mon Sep 17 00:00:00 2001
From: Albert Santoni <albert.santoni@sourcefabric.org>
Date: Thu, 26 Mar 2015 12:08:52 -0400
Subject: [PATCH] S3 proxy cache support + 1 minor analyzer bugfix

---
 .../cloud_storage/Amazon_S3StorageBackend.php | 48 ++++++++++++++++---
 .../airtime_analyzer/message_listener.py      |  1 +
 2 files changed, 43 insertions(+), 6 deletions(-)

diff --git a/airtime_mvc/application/cloud_storage/Amazon_S3StorageBackend.php b/airtime_mvc/application/cloud_storage/Amazon_S3StorageBackend.php
index b51b0059f..46feaeb82 100644
--- a/airtime_mvc/application/cloud_storage/Amazon_S3StorageBackend.php
+++ b/airtime_mvc/application/cloud_storage/Amazon_S3StorageBackend.php
@@ -9,20 +9,33 @@ class Amazon_S3StorageBackend extends StorageBackend
 {
     
     private $s3Client;
-    
+    private $proxyHost;
+
     public function Amazon_S3StorageBackend($securityCredentials)
     {
         $this->setBucket($securityCredentials['bucket']);
         $this->setAccessKey($securityCredentials['api_key']);
         $this->setSecretKey($securityCredentials['api_key_secret']);
 
-        $this->s3Client = S3Client::factory(array(
+        $s3Options = array(
             'key' => $securityCredentials['api_key'],
             'secret' => $securityCredentials['api_key_secret'],
             'region' => $securityCredentials['region']
-        ));
-    }
+        );
+        if (array_key_exists("proxy_host", $securityCredentials)) {
+            $s3Options = array_merge($s3Options, array(
+                //'base_url' => "http://" . $securityCredentials['proxy_host'],
+                'base_url' => "http://s3.amazonaws.com",
+                'scheme' => "http",
+                //'force_path_style'  => true,
+                'signature' => 'v4'
+            ));
+            $this->proxyHost = $securityCredentials['proxy_host'];
+        }
     
+        $this->s3Client = S3Client::factory($s3Options);
+    }
+
     public function getAbsoluteFilePath($resourceId)
     {
         return $this->s3Client->getObjectUrl($this->getBucket(), $resourceId);
@@ -30,9 +43,32 @@ class Amazon_S3StorageBackend extends StorageBackend
 
     public function getSignedURL($resourceId)
     {
-        return $this->s3Client->getObjectUrl($this->getBucket(), $resourceId, '+60 minutes');
+        $url = $this->s3Client->getObjectUrl($this->getBucket(), $resourceId, '+60 minutes');
+
+        //If we're using the proxy cache, we need to modify the request URL after it has
+        //been generated by the above. (The request signature must be for the amazonaws.com,
+        //not our proxy, since the proxy translates the host back to amazonaws.com)
+        if ($this->proxyHost) {
+            $p = parse_url($url);
+            $p["host"] = $this->getBucket() . "." . $this->proxyHost;
+            $p["scheme"] = "http";
+            //If the path contains the bucket name (which is the case with HTTPS requests to Amazon),
+            //we need to strip that part out, since we're forcing everything to HTTP. The Amazon S3
+            //URL convention for HTTP is to prepend the bucket name to the hostname instead of having
+            //it in the path.
+            //eg. http://bucket.s3.amazonaws.com/ instead of https://s3.amazonaws.com/bucket/
+            if (strpos($p["path"], $this->getBucket()) == 1) {
+                $p["path"] = substr($p["path"], 1 + strlen($this->getBucket()));
+            }
+            $url = $p["scheme"] . "://" . $p["host"] . $p["path"] . "?" . $p["query"];
+        }
+        //http_build_url() would be nice to use but it requires pecl_http :-(
+
+        Logging::info($url);
+
+        return $url;
     }
-    
+
     public function deletePhysicalFile($resourceId)
     {
         $bucket = $this->getBucket();
diff --git a/python_apps/airtime_analyzer/airtime_analyzer/message_listener.py b/python_apps/airtime_analyzer/airtime_analyzer/message_listener.py
index 111471153..89ca24fdf 100644
--- a/python_apps/airtime_analyzer/airtime_analyzer/message_listener.py
+++ b/python_apps/airtime_analyzer/airtime_analyzer/message_listener.py
@@ -226,6 +226,7 @@ class MessageListener:
         else:
             raise Exception("Analyzer process terminated unexpectedly.")
         '''
+        results = {}
 
         q = Queue.Queue()
         try: