Fixing file info caching issue with Aurora for master (#5477)

api/post.go

@@ -421,13 +421,16 @@ func getFileInfosForPost(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if infos, err := app.GetFileInfosForPost(postId); err != nil {
+	if infos, err := app.GetFileInfosForPost(postId, false); err != nil {
 		c.Err = err
 		return
 	} else if HandleEtag(model.GetEtagForFileInfos(infos), "Get File Infos For Post", w, r) {
 		return
 	} else {
-		w.Header().Set("Cache-Control", "max-age=2592000, public")
+		if len(infos) > 0 {
+			w.Header().Set("Cache-Control", "max-age=2592000, public")
+		}
+
 		w.Header().Set(model.HEADER_ETAG_SERVER, model.GetEtagForFileInfos(infos))
 		w.Write([]byte(model.FileInfosToJson(infos)))
 	}

api/post_test.go

@@ -136,7 +136,7 @@ func TestCreatePost(t *testing.T) {
 	} else if rpost9 := resp.Data.(*model.Post); len(rpost9.FileIds) != 3 {
 		t.Fatal("post should have 3 files")
 	} else {
-		infos := store.Must(app.Srv.Store.FileInfo().GetForPost(rpost9.Id, true)).([]*model.FileInfo)
+		infos := store.Must(app.Srv.Store.FileInfo().GetForPost(rpost9.Id, true, true)).([]*model.FileInfo)
 
 		if len(infos) != 3 {
 			t.Fatal("should've attached all 3 files to post")