From 019fdd65e9dc61bc35b1099e450ec12e4dcd1e21 Mon Sep 17 00:00:00 2001
From: Andy Miller <rhuk@mac.com>
Date: Tue, 16 Jun 2015 09:58:56 -0600
Subject: [PATCH] added toggles to enable/disable `last_modified` and `etag`
 headers

---
 system/config/system.yaml       |  2 ++
 system/src/Grav/Common/Grav.php | 10 +++++++---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/system/config/system.yaml b/system/config/system.yaml
index 98e183b1a..e438e6b4a 100644
--- a/system/config/system.yaml
+++ b/system/config/system.yaml
@@ -32,6 +32,8 @@ pages:
       '<': 'lt'
   types: 'txt|xml|html|json|rss|atom'  # Pipe separated list of valid page types
   expires: 0                           # Page expires time in seconds (604800 seconds = 7 days)
+  last_modified: true                  # Set the last modified header
+  etag: true                           # Set the expires header tag
 
 cache:
   enabled: true                        # Set to true to enable caching
diff --git a/system/src/Grav/Common/Grav.php b/system/src/Grav/Common/Grav.php
index 710984aca..0c8b5348e 100644
--- a/system/src/Grav/Common/Grav.php
+++ b/system/src/Grav/Common/Grav.php
@@ -312,11 +312,15 @@ class Grav extends Container
         }
 
         // Set the last modified time
-        $last_modified_date = gmdate('D, d M Y H:i:s', $page->modified()) . ' GMT';
-        header('Last-Modified: ' . $last_modified_date);
+        if ($this['config']->get('system.pages.last_modified')) {
+            $last_modified_date = gmdate('D, d M Y H:i:s', $page->modified()) . ' GMT';
+            header('Last-Modified: ' . $last_modified_date);
+        }
 
         // Calculate a Hash based on the raw file
-        header('ETag: ' . md5($page->raw().$page->modified()));
+        if ($this['config']->get('system.pages.etag')) {
+            header('ETag: ' . md5($page->raw() . $page->modified()));
+        }
 
         // Set debugger data in headers
         if (!($extension === null || $extension == 'html')) {