From b0c94ff56e3f7cc4d378992abe337d3fa52d9e9e Mon Sep 17 00:00:00 2001
From: Michael Kaye <1917473+michaelkaye@users.noreply.github.com>
Date: Thu, 6 Jun 2019 09:57:49 +0100
Subject: [PATCH] Use boto3 session from localdata.

This prevents issues when the thread-unsafe Session() is
used by multiple threads by allocating one in local_data.
---
 s3_storage_provider.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/s3_storage_provider.py b/s3_storage_provider.py
index 28cfe2d..5dedc53 100644
--- a/s3_storage_provider.py
+++ b/s3_storage_provider.py
@@ -141,7 +141,10 @@ class _S3DownloadThread(threading.Thread):
         self.deferred = deferred
 
     def run(self):
-        session = boto3.session.Session()
+        local_data = threading.local()
+        if not hasattr(local_data, "b3_session"):
+            local_data.b3_session = boto3.session.Session()
+        session = local_data.b3_session
         s3 = session.client('s3', **self.api_kwargs)
 
         try: