From 7e5d5c77ee8eb724d4c85f745ee0ecb0036be2d3 Mon Sep 17 00:00:00 2001
From: Jarek Potiuk <jarek@potiuk.com>
Date: Mon, 20 Apr 2020 01:39:36 +0200
Subject: [PATCH] Fix case when the pidfile is empty during the pidfile check

---
 airflow/utils/process_utils.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/airflow/utils/process_utils.py b/airflow/utils/process_utils.py
index 2e5b7e2928529b..1cc87e73e61f69 100644
--- a/airflow/utils/process_utils.py
+++ b/airflow/utils/process_utils.py
@@ -270,6 +270,8 @@ def check_if_pidfile_process_is_running(pid_file: str, process_name: str):
     if pid_lock_file.is_locked():
         # Read the pid
         pid = pid_lock_file.read_pid()
+        if pid is None:
+            return
         try:
             # Check if process is still running
             proc = psutil.Process(pid)