From 7cac6a6f720cd3cdbd9b690e173ee3ce3e1f477f Mon Sep 17 00:00:00 2001
From: Diederik van der Boor <vdboor@edoburu.nl>
Date: Thu, 26 Apr 2018 11:56:08 +0200
Subject: [PATCH] Enforce tornado 4.x until the Tornado 5.0 support is fixed

Tornado 5.x starts it's own event loop, breaking other packages:
https://github.com/jupyter/notebook/issues/3397
http://www.tornadoweb.org/en/stable/releases/v5.0.0.html#backwards-compatibility-notes
---
 Makefile | 2 +-
 setup.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 7da53ecae..4ce9cc35b 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 .PHONY: install clean test retest coverage docs
 
 install:
-	pip install -e .[docs,test,async]
+	pip install -e .[docs,test,async,tornado]
 	pip install bumpversion twine wheel
 
 lint:
diff --git a/setup.py b/setup.py
index 057773a6e..9fa1c1558 100755
--- a/setup.py
+++ b/setup.py
@@ -20,7 +20,7 @@
 ]
 
 tornado_require = [
-    'tornado>=4.0.2'
+    'tornado>=4.0.2,<5'
 ]
 
 async_require = []  # see below