use subprocess call

files/geant_acme_web.py

@@ -33,7 +33,7 @@ def index(provider=None, filename=None):
         return send_from_directory(APP.static_folder, filename)
 
     if url_name in OTHER_URLS:
-        sp.Popen(["cert2json.sh", provider], stdout=sp.PIPE, stderr=sp.PIPE)
+        sp.call(["cert2json.sh", provider])
         return render_template("{}/{}".format(provider, filename))
 
     if url_name in BASE_URLS: