From c4632cda1a8dc731ae47e73ee53ee7fbcb3f61ac Mon Sep 17 00:00:00 2001
From: Romain Quetiez <romain.quetiez@combodo.com>
Date: Wed, 4 Jun 2014 13:10:23 +0000
Subject: [PATCH] Added a helper function to get an icon stored as an
 ormDocument: ormDocument::GetDownloadURL

SVN:trunk[3191]
---
 core/ormdocument.class.inc.php | 13 ++++++++++++-
 pages/ajax.render.php          |  6 ++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/core/ormdocument.class.inc.php b/core/ormdocument.class.inc.php
index 94625b175..72a897f05 100644
--- a/core/ormdocument.class.inc.php
+++ b/core/ormdocument.class.inc.php
@@ -117,7 +117,18 @@ class ormDocument
 	{
 		return "<a href=\"".utils::GetAbsoluteUrlAppRoot()."pages/ajax.render.php?operation=download_document&class=$sClass&id=$Id&field=$sAttCode\">".$this->GetFileName()."</a>\n";
 	}
-	
+
+	/**
+	 * Returns an URL to download a document like an image (uses HTTP caching)
+	 * @return string
+	 */	 	 	
+	public function GetDownloadURL($sClass, $Id, $sAttCode)
+	{
+		// Compute a signature to reset the cache anytime the data changes (this is acceptable if used only with icon files)
+		$sSignature = md5($this->GetData());
+		return utils::GetAbsoluteUrlAppRoot()."pages/ajax.render.php?operation=download_document&class=$sClass&id=$Id&field=$sAttCode&s=$sSignature&cache=86400";
+	}
+
 	
 	public function IsPreviewAvailable()
 	{
diff --git a/pages/ajax.render.php b/pages/ajax.render.php
index 1bef4cf81..547c4c83d 100644
--- a/pages/ajax.render.php
+++ b/pages/ajax.render.php
@@ -778,9 +778,15 @@ try
 		case 'download_document':
 		$id = utils::ReadParam('id', '');
 		$sField = utils::ReadParam('field', '');
+		$iCacheSec = (int) utils::ReadParam('cache', 0);
 		if (!empty($sClass) && !empty($id) && !empty($sField))
 		{
 			DownloadDocument($oPage, $sClass, $id, $sField, 'attachment');
+			if ($iCacheSec > 0)
+			{
+				$oPage->add_header("Expires: "); // Reset the value set in ajax_page
+				$oPage->add_header("Cache-Control: no-transform,public,max-age=$iCacheSec,s-maxage=$iCacheSec");
+			}
 		}
 		break;