From 3e6fed8df4911647fefe5f93064254d65557866d Mon Sep 17 00:00:00 2001
From: Daniel Schalla <daniel@schalla.me>
Date: Tue, 21 May 2019 17:10:39 +0200
Subject: [PATCH] [MM-15641] Set stricter caching policy for file downloads
 (#10857)

* Set stricter caching policy for file downloads

* Add private directive back to caching header for file downloads
---
 api4/file.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/api4/file.go b/api4/file.go
index 5a0da880ba..9ed8be9230 100644
--- a/api4/file.go
+++ b/api4/file.go
@@ -737,7 +737,7 @@ func getPublicFile(c *Context, w http.ResponseWriter, r *http.Request) {
 }
 
 func writeFileResponse(filename string, contentType string, contentSize int64, webserverMode string, fileReader io.Reader, forceDownload bool, w http.ResponseWriter, r *http.Request) *model.AppError {
-	w.Header().Set("Cache-Control", "max-age=2592000, private")
+	w.Header().Set("Cache-Control", "private, no-cache")
 	w.Header().Set("X-Content-Type-Options", "nosniff")
 
 	if contentSize > 0 {