change(cache): use cache-specific http headers for their lifetime

This uses the 'Age', 'Cache-Control' and 'Expires' HTTP headers to more
accurately set up the cache lifetime, falling back to a static 1-week
time if they're not present in the response.

Signed-off-by: flow <flowlnlnln@gmail.com>

1 files changed, 6 insertions, 8 deletions

diff --git a/launcher/net/HttpMetaCache.cpp b/launcher/net/HttpMetaCache.cpp
index 769f162b..deb2780b 100644
--- a/launcher/net/HttpMetaCache.cpp
+++ b/launcher/net/HttpMetaCache.cpp
@@ -44,11 +44,6 @@
 
 #include <QDebug>
 
-/** Maximum time to hold a cache entry
- *  = 1 week in milliseconds
- */
-#define TIME_TO_EXPIRE 1*7*24*60*60*1000
-
 auto MetaEntry::getFullPath() -> QString
 {
     // FIXME: make local?
@@ -127,9 +122,8 @@ auto HttpMetaCache::resolveEntry(QString base, QString resource_path, QString ex
     }
 
     // Get rid of old entries, to prevent cache problems
-    auto current_time = QDateTime::currentMSecsSinceEpoch();
-    auto remote_time = QDateTime::fromString(entry->remote_changed_timestamp).toMSecsSinceEpoch();
-    if (current_time - remote_time < TIME_TO_EXPIRE) {
+    auto current_time = QDateTime::currentSecsSinceEpoch();
+    if (entry->isExpired(current_time - ( file_last_changed / 1000 ))) {
         qWarning() << "Removing cache entry because of old age!";
         selected_base.entry_list.remove(resource_path);
         return staleEntry(base, resource_path);
@@ -235,6 +229,8 @@ void HttpMetaCache::Load()
         foo->etag = Json::ensureString(element_obj, "etag");
         foo->local_changed_timestamp = Json::ensureDouble(element_obj, "last_changed_timestamp");
         foo->remote_changed_timestamp = Json::ensureString(element_obj, "remote_changed_timestamp");
+        foo->current_age = Json::ensureDouble(element_obj, "current_age");
+        foo->max_age = Json::ensureDouble(element_obj, "max_age");
         // presumed innocent until closer examination
         foo->stale = false;
 
@@ -275,6 +271,8 @@ void HttpMetaCache::SaveNow()
             entryObj.insert("last_changed_timestamp", QJsonValue(double(entry->local_changed_timestamp)));
             if (!entry->remote_changed_timestamp.isEmpty())
                 entryObj.insert("remote_changed_timestamp", QJsonValue(entry->remote_changed_timestamp));
+            entryObj.insert("current_age", QJsonValue(double(entry->current_age)));
+            entryObj.insert("max_age", QJsonValue(double(entry->max_age)));
             entriesArr.append(entryObj);
         }
     }