Use timezone package as Python 3.5+ is required (#694)

* Use timezone package as Python 3.5+ is required

This method is deprecated:
https://docs.python.org/3/library/datetime.html#datetime.datetime.utcnow

Replaced with:
https://docs.python.org/3/library/datetime.html#datetime.datetime.utcnow
using:
https://docs.python.org/3/library/datetime.html#datetime.timezone.utc

which seems to indicate this was added in Python 3.2

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

docs/usage.rst

@@ -119,7 +119,7 @@ datetime, which will be converted into an int. For example:
 .. code-block:: python
 
     jwt.encode({"exp": 1371720939}, "secret")
-    jwt.encode({"exp": datetime.utcnow()}, "secret")
+    jwt.encode({"exp": datetime.now(tz=timezone.utc)}, "secret")
 
 Expiration time is automatically verified in `jwt.decode()` and raises
 `jwt.ExpiredSignatureError` if the expiration time is in the past:
@@ -133,7 +133,7 @@ Expiration time is automatically verified in `jwt.decode()` and raises
         ...
 
 Expiration time will be compared to the current UTC time (as given by
-`timegm(datetime.utcnow().utctimetuple())`), so be sure to use a UTC timestamp
+`timegm(datetime.now(tz=timezone.utc).utctimetuple())`), so be sure to use a UTC timestamp
 or datetime in encoding.
 
 You can turn off expiration time verification with the `verify_exp` parameter in the options argument.
@@ -147,7 +147,8 @@ you can set a leeway of 10 seconds in order to have some margin:
 .. code-block:: python
 
     jwt_payload = jwt.encode(
-        {"exp": datetime.datetime.utcnow() + datetime.timedelta(seconds=30)}, "secret"
+        {"exp": datetime.datetime.now(tz=timezone.utc) + datetime.timedelta(seconds=30)},
+        "secret",
     )
 
     time.sleep(32)
@@ -181,7 +182,7 @@ The `nbf` claim works similarly to the `exp` claim above.
 .. code-block:: python
 
     jwt.encode({"nbf": 1371720939}, "secret")
-    jwt.encode({"nbf": datetime.utcnow()}, "secret")
+    jwt.encode({"nbf": datetime.now(tz=timezone.utc)}, "secret")
 
 Issuer Claim (iss)
 ~~~~~~~~~~~~~~~~~~
@@ -259,7 +260,7 @@ Issued At Claim (iat)
 .. code-block:: python
 
     jwt.encode({"iat": 1371720939}, "secret")
-    jwt.encode({"iat": datetime.utcnow()}, "secret")
+    jwt.encode({"iat": datetime.now(tz=timezone.utc)}, "secret")
 
 Requiring Presence of Claims
 ----------------------------

jwt/api_jwt.py

@@ -1,7 +1,7 @@
 import json
 from calendar import timegm
 from collections.abc import Iterable, Mapping
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, timezone
 from typing import Any, Dict, List, Optional, Type, Union
 
 from . import api_jws
@@ -133,7 +133,7 @@ def _validate_claims(self, payload, options, audience, issuer, leeway):
 
         self._validate_required_claims(payload, options)
 
-        now = timegm(datetime.utcnow().utctimetuple())
+        now = timegm(datetime.now(tz=timezone.utc).utctimetuple())
 
         if "iat" in payload and options["verify_iat"]:
             self._validate_iat(payload, now, leeway)

tests/test_api_jwt.py

@@ -1,7 +1,7 @@
 import json
 import time
 from calendar import timegm
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, timezone
 from decimal import Decimal
 
 import pytest
@@ -252,7 +252,7 @@ def test_decode_raises_exception_if_aud_is_none(self, jwt):
 
     def test_encode_datetime(self, jwt):
         secret = "secret"
-        current_datetime = datetime.utcnow()
+        current_datetime = datetime.now(tz=timezone.utc)
         payload = {
             "exp": current_datetime,
             "iat": current_datetime,
@@ -499,7 +499,7 @@ def test_skip_check_audience(self, jwt):
     def test_skip_check_exp(self, jwt):
         payload = {
             "some": "payload",
-            "exp": datetime.utcnow() - timedelta(days=1),
+            "exp": datetime.now(tz=timezone.utc) - timedelta(days=1),
         }
         token = jwt.encode(payload, "secret")
         jwt.decode(
@@ -576,7 +576,7 @@ def test_skip_check_signature(self, jwt):
     def test_skip_check_iat(self, jwt):
         payload = {
             "some": "payload",
-            "iat": datetime.utcnow() + timedelta(days=1),
+            "iat": datetime.now(tz=timezone.utc) + timedelta(days=1),
         }
         token = jwt.encode(payload, "secret")
         jwt.decode(
@@ -589,7 +589,7 @@ def test_skip_check_iat(self, jwt):
     def test_skip_check_nbf(self, jwt):
         payload = {
             "some": "payload",
-            "nbf": datetime.utcnow() + timedelta(days=1),
+            "nbf": datetime.now(tz=timezone.utc) + timedelta(days=1),
         }
         token = jwt.encode(payload, "secret")
         jwt.decode(

tests/utils.py

@@ -1,14 +1,14 @@
 import os
 from calendar import timegm
-from datetime import datetime
+from datetime import datetime, timezone
 
 import pytest
 
 from jwt.algorithms import has_crypto
 
 
 def utc_timestamp():
-    return timegm(datetime.utcnow().utctimetuple())
+    return timegm(datetime.now(tz=timezone.utc).utctimetuple())
 
 
 def key_path(key_name):