diff --git a/tests/test_nginx_vhosts.py b/tests/test_nginx_vhosts.py
index 2e12545f4e87abf42177d3510050d44ffe10fb80..7cecdf9c44a548ee3f333e07ba2ce6c714220743 100755
--- a/tests/test_nginx_vhosts.py
+++ b/tests/test_nginx_vhosts.py
@@ -1,41 +1,51 @@
 #!/usr/bin/env python3
-# -*- coding: utf-8 -*-
-'''
+
+"""
 Criticality: High
 Tests that all webserver services (vhosts) are available and reachable.
-'''
+"""
+
 import imp
 import os
 import re
 import requests
 import socket
 import sys
+
 try:
     from requests.packages.urllib3.exceptions import InsecureRequestWarning
+
     requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
 except ImportError:
     requests.packages.urllib3.disable_warnings()
 
-'''
+"""
 This script checks for all enabled vhosts in Nginx conf that:
 * The response status code is 200, 401 or 403.
 * The host is resolved as 127.0.0.1.
 * The Wowza response is correct on /streaming/ (only for mediaserver vhosts).
-'''
+"""
 
 
-def test_vhost(ports_info=None, domains=None, resolution_ignored=None, celerity_conf=''):
+def test_vhost(
+    ports_info=None, domains=None, resolution_ignored=None, celerity_conf=""
+):
     tested = 0
     errors = 0
     warnings = 0
-    for port, https in (ports_info or [(80, False)]):
-        for domain in (domains or ['localhost']):
+    for port, https in ports_info or [(80, False)]:
+        for domain in domains or ["localhost"]:
             tested += 1
-            url = '%s://%s:%s' % ('https' if https else 'http', domain, port)
+            url = "%s://%s:%s" % ("https" if https else "http", domain, port)
             sys.stdout.write('Testing url "%s":\n' % url)
-            if name.startswith('mediaserver'):
-                if not celerity_conf or not re.search(r'http[s]{0,1}://%s' % domain, celerity_conf):
-                    sys.stdout.write('\033[93mWarning:\033[0m Url "%s" not found in celerity conf; it should also be set in the MediaWorker.\n' % url)
+            if name.startswith("mediaserver"):
+                if not celerity_conf or not re.search(
+                    r"http[s]{0,1}://%s" % domain, celerity_conf
+                ):
+                    sys.stdout.write(
+                        '\033[93mWarning:\033[0m Url "%s" not found in celerity conf; it should also be set in the MediaWorker.\n'
+                        % url
+                    )
                     warnings += 1
             # test domain IP
             ip_error = None
@@ -43,50 +53,62 @@ def test_vhost(ports_info=None, domains=None, resolution_ignored=None, celerity_
             try:
                 ip = socket.gethostbyname(domain)
             except Exception as e:
-                ip_error = 'domain is not resolved: %s' % e
+                ip_error = "domain is not resolved: %s" % e
             else:
-                if ip != '127.0.0.1':
-                    ip_warning = 'domain is resolved with %s instead of 127.0.0.1' % ip
-            sys.stdout.write('  IP: ')
+                if ip != "127.0.0.1":
+                    ip_warning = "domain is resolved with %s instead of 127.0.0.1" % ip
+            sys.stdout.write("  IP: ")
             if ip_error:
                 if resolution_ignored and domain in resolution_ignored:
-                    sys.stdout.write('\033[94mIgnored (%s)\033[0m' % ip_error)
+                    sys.stdout.write("\033[94mIgnored (%s)\033[0m" % ip_error)
                     ip_error = None
                 else:
-                    sys.stdout.write('\033[91mKO (%s)\033[0m' % ip_error)
+                    sys.stdout.write("\033[91mKO (%s)\033[0m" % ip_error)
             elif ip_warning:
                 if resolution_ignored and domain in resolution_ignored:
-                    sys.stdout.write('\033[94mIgnored (%s)\033[0m' % ip_warning)
+                    sys.stdout.write("\033[94mIgnored (%s)\033[0m" % ip_warning)
                     ip_warning = None
                 else:
-                    sys.stdout.write('\033[93mWarning (%s)\033[0m' % ip_warning)
+                    sys.stdout.write("\033[93mWarning (%s)\033[0m" % ip_warning)
             else:
-                sys.stdout.write('\033[92mOK (127.0.0.1)\033[0m')
+                sys.stdout.write("\033[92mOK (127.0.0.1)\033[0m")
             # test url
-            sys.stdout.write(', status: ')
+            sys.stdout.write(", status: ")
             req_error = False
             try:
-                req = requests.get(url, verify=False, proxies={'http': '', 'https': ''}, timeout=30)
+                req = requests.get(
+                    url, verify=False, proxies={"http": "", "https": ""}, timeout=30
+                )
                 req_time = int(1000 * req.elapsed.total_seconds())
             except Exception as e:
                 code = str(e)
                 req_time = 0
             else:
                 code = req.status_code
-            if domain != 'localhost' and code not in (200, 401, 403) or domain == 'localhost' and code not in (200, 401, 403, 404):
-                sys.stdout.write('\033[91mKO (%s, %sms)\033[0m' % (code, req_time))
+            if (
+                domain != "localhost"
+                and code not in (200, 401, 403)
+                or domain == "localhost"
+                and code not in (200, 401, 403, 404)
+            ):
+                sys.stdout.write("\033[91mKO (%s, %sms)\033[0m" % (code, req_time))
                 req_error = True
             else:
                 if req_time > 10000:
-                    sys.stdout.write('\033[93mOK (%s, %sms)\033[0m' % (code, req_time))
+                    sys.stdout.write("\033[93mOK (%s, %sms)\033[0m" % (code, req_time))
                     warnings += 1
                 else:
-                    sys.stdout.write('\033[92mOK (%s, %sms)\033[0m' % (code, req_time))
-                if 'mediaserver' in name and wowza_dir:
+                    sys.stdout.write("\033[92mOK (%s, %sms)\033[0m" % (code, req_time))
+                if "mediaserver" in name and wowza_dir:
                     # test /streaming url
-                    sys.stdout.write(', streaming: ')
+                    sys.stdout.write(", streaming: ")
                     try:
-                        req = requests.get(url + '/streaming/', verify=False, proxies={'http': '', 'https': ''}, timeout=30)
+                        req = requests.get(
+                            url + "/streaming/",
+                            verify=False,
+                            proxies={"http": "", "https": ""},
+                            timeout=30,
+                        )
                         req_time = int(1000 * req.elapsed.total_seconds())
                     except Exception as e:
                         code = str(e)
@@ -94,13 +116,19 @@ def test_vhost(ports_info=None, domains=None, resolution_ignored=None, celerity_
                     else:
                         code = req.status_code
                     if code != 200:
-                        sys.stdout.write('\033[91mKO (%s, %sms)\033[0m' % (code, req_time))
+                        sys.stdout.write(
+                            "\033[91mKO (%s, %sms)\033[0m" % (code, req_time)
+                        )
                         req_error = True
                     elif req_time > 10000:
-                        sys.stdout.write('\033[93mOK (%s, %sms)\033[0m' % (code, req_time))
+                        sys.stdout.write(
+                            "\033[93mOK (%s, %sms)\033[0m" % (code, req_time)
+                        )
                     else:
-                        sys.stdout.write('\033[92mOK (%s, %sms)\033[0m' % (code, req_time))
-            sys.stdout.write('.\n')
+                        sys.stdout.write(
+                            "\033[92mOK (%s, %sms)\033[0m" % (code, req_time)
+                        )
+            sys.stdout.write(".\n")
 
             if ip_warning:
                 warnings += 1
@@ -110,36 +138,38 @@ def test_vhost(ports_info=None, domains=None, resolution_ignored=None, celerity_
     return tested, warnings, errors
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     # check that Nginx dir exists
-    nginx_dir = '/etc/nginx/sites-enabled'
+    nginx_dir = "/etc/nginx/sites-enabled"
     if not os.path.exists(nginx_dir):
         print('Nginx dir does not exists ("%s").' % nginx_dir)
         sys.exit(2)
 
     # check that Wowza is installed
-    wowza_dir = '/usr/local/WowzaStreamingEngine'
+    wowza_dir = "/usr/local/WowzaStreamingEngine"
     if not os.path.exists(wowza_dir):
         print('Info: Wowza is not installed ("%s" does not exist).' % wowza_dir)
         wowza_dir = None
     else:
-        print('Info: Wowza is installed, /streaming/ will be tested on mediaserver vhosts.')
+        print(
+            "Info: Wowza is installed, /streaming/ will be tested on mediaserver vhosts."
+        )
 
     # get envsetup conf
     conf = dict()
     os.chdir(os.path.dirname(__file__))
-    if os.path.isfile('../utils.py'):
-        es_utils = imp.load_source('es_utils', '../utils.py')
+    if os.path.isfile("../utils.py"):
+        es_utils = imp.load_source("es_utils", "../utils.py")
         conf = es_utils.load_conf()
 
     # get celerity conf
-    celerity_conf = ''
-    if os.path.exists('/etc/celerity/config.py'):
-        with open('/etc/celerity/config.py', 'r') as fo:
+    celerity_conf = ""
+    if os.path.exists("/etc/celerity/config.py"):
+        with open("/etc/celerity/config.py", "r") as fo:
             celerity_conf = fo.read()
 
     # get enabled vhosts
-    resolution_ignored = conf.get('TESTER_VHOST_RESOLUTION_IGNORED', '').split(',')
+    resolution_ignored = conf.get("TESTER_VHOST_RESOLUTION_IGNORED", "").split(",")
     tested = 0
     errors = 0
     warnings = 0
@@ -151,19 +181,21 @@ if __name__ == '__main__':
         domains = list()
         ports_info = list()
         print('Parsing vhost "%s"...' % path)
-        with open(path, 'r') as fo:
+        with open(path, "r") as fo:
             for line in fo:
                 line = line.strip()
-                if not line or line.startswith('#'):
+                if not line or line.startswith("#"):
                     continue
-                words = re.sub(r'\s+', ' ', line).strip('; ').split(' ')
-                if '{' in words or '}' in words:
-                    level += words.count('{')
-                    level -= words.count('}')
+                words = re.sub(r"\s+", " ", line).strip("; ").split(" ")
+                if "{" in words or "}" in words:
+                    level += words.count("{")
+                    level -= words.count("}")
                     if level == 0:
                         # test
                         if ports_info or domains:
-                            t, w, e = test_vhost(ports_info, domains, resolution_ignored, celerity_conf)
+                            t, w, e = test_vhost(
+                                ports_info, domains, resolution_ignored, celerity_conf
+                            )
                             tested += t
                             warnings += w
                             errors += e
@@ -171,23 +203,23 @@ if __name__ == '__main__':
                         ports_info = list()
                 elif level == 1:
                     # server section are level 1
-                    if words[0] == 'listen':
-                        https = 'ssl' in words
+                    if words[0] == "listen":
+                        https = "ssl" in words
                         for port in words:
                             try:
-                                port = int(port.split(':')[-1])
+                                port = int(port.split(":")[-1])
                             except ValueError:
                                 pass
                             else:
                                 ports_info.append((port, https))
-                    elif words[0] == 'server_name':
+                    elif words[0] == "server_name":
                         domains = words[1:]
 
     if errors:
-        print('%s url(s) did not correctly respond.' % errors)
+        print("%s url(s) did not correctly respond." % errors)
         sys.exit(1)
     elif warnings:
         sys.exit(3)
     if not tested:
-        print('No url found in Nginx sites-enabled dir.')
+        print("No url found in Nginx sites-enabled dir.")
         sys.exit(1)