diff --git a/app/app.py b/app/app.py
index 6a78a1d..0bbe02a 100644
--- a/app/app.py
+++ b/app/app.py
@@ -3,18 +3,20 @@ import os
 import tempfile
 import uuid
 from functools import wraps
+from html import unescape
 
 import argostranslatefiles
 from argostranslatefiles import get_supported_formats
-from flask import Flask, abort, jsonify, render_template, request, url_for, send_file
+from flask import (Flask, abort, jsonify, render_template, request, send_file,
+                   url_for)
 from flask_swagger import swagger
 from flask_swagger_ui import get_swaggerui_blueprint
 from translatehtml import translate_html
 from werkzeug.utils import secure_filename
-from html import unescape
 
 from app import flood, remove_translated_files, security
 from app.language import detect_languages, transliterate
+
 from .api_keys import Database
 from .suggestions import Database as SuggestionsDatabase
 
@@ -140,7 +142,6 @@ def create_app(args):
         else:
             frontend_argos_language_target = languages[0]
 
-
     api_keys_db = None
 
     if args.req_limit > 0 or args.api_keys or args.daily_req_limit > 0:
@@ -174,11 +175,19 @@ def create_app(args):
                 if flood.has_violation(ip):
                     flood.decrease(ip)
 
-            if args.api_keys and args.require_api_key_origin:
+            if args.api_keys:
                 ak = get_req_api_key()
-
                 if (
-                        api_keys_db.lookup(ak) is None and request.headers.get("Origin") != args.require_api_key_origin
+                    ak and api_keys_db.lookup(ak) is None
+                ):
+                    abort(
+                        403,
+                        description="Invalid API key",
+                    )
+                elif (
+                    args.require_api_key_origin
+                    and api_keys_db.lookup(ak) is None
+                    and request.headers.get("Origin") != args.require_api_key_origin
                 ):
                     abort(
                         403,
diff --git a/app/default_values.py b/app/default_values.py
index b6fff3f..9161aa6 100644
--- a/app/default_values.py
+++ b/app/default_values.py
@@ -2,16 +2,19 @@ import os
 
 _prefix = 'LT_'
 
+
 def _get_value_str(name, default_value):
     env_value = os.environ.get(name)
     return default_value if env_value is None else env_value
 
+
 def _get_value_int(name, default_value):
     try:
         return int(os.environ[name])
     except:
         return default_value
 
+
 def _get_value_bool(name, default_value):
     env_value = os.environ.get(name)
     if env_value in ['FALSE', 'False', 'false', '0']:
@@ -20,6 +23,7 @@ def _get_value_bool(name, default_value):
         return True
     return default_value
 
+
 def _get_value(name, default_value, value_type):
     env_name = _prefix + name
     if value_type == 'str':
@@ -30,6 +34,7 @@ def _get_value(name, default_value, value_type):
         return _get_value_bool(env_name, default_value)
     return default_value
 
+
 _default_options_objects = [
     {
         'name': 'HOST',
@@ -114,7 +119,7 @@ _default_options_objects = [
     {
         'name': 'SUGGESTIONS',
         'default_value': False,
-        'value_type':  'bool'
+        'value_type': 'bool'
     },
     {
         'name': 'DISABLE_FILES_TRANSLATION',
@@ -129,4 +134,4 @@ _default_options_objects = [
 ]
 
 
-DEFAULT_ARGUMENTS = { obj['name']:_get_value(**obj) for obj in _default_options_objects}
+DEFAULT_ARGUMENTS = {obj['name']: _get_value(**obj) for obj in _default_options_objects}
diff --git a/app/flood.py b/app/flood.py
index 3aa2c74..bc7fc1d 100644
--- a/app/flood.py
+++ b/app/flood.py
@@ -22,6 +22,7 @@ def forgive_banned():
     for ip in clear_list:
         del banned[ip]
 
+
 def setup(violations_threshold=100):
     global active
     global threshold
diff --git a/app/main.py b/app/main.py
index ab0e61c..62d4d6e 100644
--- a/app/main.py
+++ b/app/main.py
@@ -1,6 +1,6 @@
 import argparse
-import sys
 import operator
+import sys
 
 from app.app import create_app
 from app.default_values import DEFAULT_ARGUMENTS as DEFARGS
diff --git a/app/security.py b/app/security.py
index 56913ce..99415da 100644
--- a/app/security.py
+++ b/app/security.py
@@ -1,8 +1,10 @@
 import os
 
+
 class SuspiciousFileOperation(Exception):
     pass
 
+
 def path_traversal_check(unsafe_path, known_safe_path):
     known_safe_path = os.path.abspath(known_safe_path)
     unsafe_path = os.path.abspath(unsafe_path)
diff --git a/app/suggestions.py b/app/suggestions.py
index 28b943a..281ca38 100644
--- a/app/suggestions.py
+++ b/app/suggestions.py
@@ -1,5 +1,4 @@
 import sqlite3
-import uuid
 
 from expiringdict import ExpiringDict