From 5e2238eccfccff384b9402b77d77acc39a779bf6 Mon Sep 17 00:00:00 2001
From: xlecours <xavier.lecoursboucher@mcgill.ca>
Date: Wed, 24 Apr 2019 11:53:53 -0400
Subject: [PATCH] adding Etag headers for /candidates/visits/images/Image.php

---
 htdocs/api/v0.0.3-dev/APIBase.php               | 17 ++++++++++++++++-
 .../candidates/visits/images/Image.php          |  4 +++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/htdocs/api/v0.0.3-dev/APIBase.php b/htdocs/api/v0.0.3-dev/APIBase.php
index 2870f2359b1..ee204911087 100644
--- a/htdocs/api/v0.0.3-dev/APIBase.php
+++ b/htdocs/api/v0.0.3-dev/APIBase.php
@@ -115,7 +115,9 @@ function handleRequest()
         case 'PATCH':
             $this->handlePATCH();
             break;
-
+        case 'HEAD':
+            $this->handleHEAD();
+            break;
         }
     }
 
@@ -147,6 +149,19 @@ function handleETag()
      */
     abstract function calculateETag();
 
+    /**
+     * Handle a HEAD request
+     *
+     * @return void
+     */
+    function handleHEAD()
+    {
+        $ETag = $this->calculateETag();
+        $this->header("ETag: $ETag");
+        $this->handleGET();
+        $this->JSON = null;
+    }
+
     /**
      * Handle a GET request
      *
diff --git a/htdocs/api/v0.0.3-dev/candidates/visits/images/Image.php b/htdocs/api/v0.0.3-dev/candidates/visits/images/Image.php
index fad9515c5ed..c90aadc5112 100644
--- a/htdocs/api/v0.0.3-dev/candidates/visits/images/Image.php
+++ b/htdocs/api/v0.0.3-dev/candidates/visits/images/Image.php
@@ -43,6 +43,7 @@ public function __construct($method, $CandID, $VisitLabel, $Filename)
         if (empty($this->AllowedMethods)) {
             $this->AllowedMethods = [
                                      'GET',
+                                     'HEAD',
                                     ];
         }
         $this->CandID     = $CandID;
@@ -143,7 +144,8 @@ protected function getHeader($headerName)
      */
     public function calculateETag()
     {
-        return null;
+        $filename = $this->getFullPath();
+        return hash_file('md5', $filename);
     }
 
     /**