From e00e2c22aadf9e5b9dc353c31f1b70dad488b47a Mon Sep 17 00:00:00 2001
From: Armin Ronacher <armin.ronacher@active-4.com>
Date: Thu, 25 Aug 2016 15:41:46 +0200
Subject: [PATCH] Disable logger propagation by default

---
 CHANGES          | 1 +
 flask/logging.py | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/CHANGES b/CHANGES
index 9e13bd71..1410a9ae 100644
--- a/CHANGES
+++ b/CHANGES
@@ -11,6 +11,7 @@ Version 0.12
   See pull request ``#1849``.
 - Make ``flask.safe_join`` able to join multiple paths like ``os.path.join``
   (pull request ``#1730``).
+- Disable logger propagation by default for the app logger.
 
 Version 0.11.2
 --------------
diff --git a/flask/logging.py b/flask/logging.py
index 5a1f149c..3f888a75 100644
--- a/flask/logging.py
+++ b/flask/logging.py
@@ -87,4 +87,8 @@ def create_logger(app):
     logger.__class__ = DebugLogger
     logger.addHandler(debug_handler)
     logger.addHandler(prod_handler)
+
+    # Disable propagation by default
+    logger.propagate = False
+
     return logger