1 files changed, 18 insertions, 0 deletions
diff --git a/macaroonbakery/checkers/time.py b/macaroonbakery/checkers/time.py
new file mode 100644
index 0000000..052d983
--- /dev/null
+++ b/macaroonbakery/checkers/time.py
@@ -0,0 +1,18 @@
+# Copyright 2017 Canonical Ltd.
+# Licensed under the LGPLv3, see LICENCE file for details.
+from macaroonbakery.checkers.auth_context import ContextKey
+
+
+TIME_KEY = ContextKey('time-key')
+
+
+def context_with_clock(ctx, clock):
+    ''' Returns a copy of ctx with a key added that associates it with the given
+    clock implementation, which will be used by the time-before checker
+    to determine the current time.
+    The clock should have a utcnow method that returns the current time
+    as a datetime value in UTC.
+    '''
+    if clock is None:
+        return ctx
+    return ctx.with_value(TIME_KEY, clock)