Implement a TTL on cached fetchurl/fetchTarball results

This is because we don't want to do HTTP requests on every evaluation,
even though we can prevent a full redownload via the cached ETag. The
default is one hour.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
index e382b3aac..f900fb290 100644
--- a/src/libstore/globals.cc
+++ b/src/libstore/globals.cc
@@ -143,6 +143,14 @@ bool Settings::get(const string & name, bool def)
 }
 
 
+int Settings::get(const string & name, int def)
+{
+    int res = def;
+    _get(res, name);
+    return res;
+}
+
+
 void Settings::update()
 {
     _get(tryFallback, "build-fallback");