Close threadpools after use.

module_build_service/builder/utils.py

@@ -150,8 +150,10 @@ def create_local_repo_from_koji_tag(config, tag, repo_dir, archs=None):
 
     # Download the RPMs four at a time.
     pool = ThreadPool(4)
-    pool.map(_download_file, download_args)
-    pool.close()
+    try:
+        pool.map(_download_file, download_args)
+    finally:
+        pool.close()
 
     # If we downloaded something, run the createrepo_c.
     if repo_changed:

module_build_service/utils/submit.py

@@ -134,7 +134,11 @@ def format_mmd(mmd, scmurl, session=None):
         # Check that SCM URL is valid and replace potential branches in pkg refs
         # by real SCM hash and store the result to our private xmd place in modulemd.
         pool = ThreadPool(20)
-        pkg_dicts = pool.map(_scm_get_latest, mmd.get_rpm_components().values())
+        try:
+            pkg_dicts = pool.map(_scm_get_latest, mmd.get_rpm_components().values())
+        finally:
+            pool.close()
+
         err_msg = ""
         for pkg_dict in pkg_dicts:
             if pkg_dict["error"]: