From aa6db9fccedb8da53d602aa89a1aa6023f865e24 Mon Sep 17 00:00:00 2001
From: Jan Kaluza <jkaluza@redhat.com>
Date: Mon, 20 Feb 2017 10:42:42 +0100
Subject: [PATCH] Use StopIteration in QueueBasedThreadPool to stop the
 threads.

---
 module_build_service/utils.py | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/module_build_service/utils.py b/module_build_service/utils.py
index 97ea7600..8b7c5a04 100644
--- a/module_build_service/utils.py
+++ b/module_build_service/utils.py
@@ -54,12 +54,17 @@ class Worker(Thread):
 
     def run(self):
         while True:
-            func, args, kargs = self.tasks.get()
+            task_data = self.tasks.get()
+            if task_data == StopIteration:
+                self.tasks.task_done()
+                break
+
+            func, args, kargs = task_data
             try:
                 func(*args, **kargs)
             except Exception as e:
                 # An exception happened in this thread
-                log.error(str(e))
+                log.exception("An exception happened in a worker thread.")
             finally:
                 # Mark this task as done, whether an exception happened or not
                 self.tasks.task_done()
@@ -68,6 +73,7 @@ class Worker(Thread):
 class QueueBasedThreadPool:
     """ Pool of threads consuming tasks from a queue. """
     def __init__(self, num_threads):
+        self.num_threads = num_threads
         self.tasks = Queue(num_threads)
         for _ in range(num_threads):
             Worker(self.tasks)
@@ -83,6 +89,8 @@ class QueueBasedThreadPool:
 
     def wait_completion(self):
         """ Wait for completion of all the tasks in the queue """
+        for _ in range(self.num_threads):
+            self.tasks.put(StopIteration)
         self.tasks.join()
 
 def retry(timeout=conf.net_timeout, interval=conf.net_retry_interval, wait_on=Exception):