From a9710a68db7bd8e539a89c84337729ab09767d6a Mon Sep 17 00:00:00 2001
From: Mikunj <mikunj@live.com.au>
Date: Thu, 12 Sep 2019 13:04:01 +1000
Subject: [PATCH] Purge cache on failure.

---
 js/link_previews_helper.js | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/js/link_previews_helper.js b/js/link_previews_helper.js
index 11d99eada..3fb756bad 100644
--- a/js/link_previews_helper.js
+++ b/js/link_previews_helper.js
@@ -79,7 +79,16 @@
     }
 
     // Start the request
-    const promise = _getPreview(url);
+    const promise = _getPreview(url).catch(e => {
+      window.log.error(e);
+
+      // If we get an error then we can purge the cache
+      if (url in previewCache) {
+        delete previewCache[url];
+      }
+
+      return null;
+    });
     previewCache[url] = promise;
 
     return promise;
@@ -91,7 +100,7 @@
       html = await textsecure.messaging.makeProxiedRequest(url);
     } catch (error) {
       if (error.code >= 300) {
-        return null;
+        throw new Error(`Failed to fetch html: ${error}`);
       }
     }