feat!: Remove Python 2 support (#657)

* Remove Python 2 support from setup.py and noxfile.py

* Remove Py2 compatibility code, except in system tests

* Remove Py2 compatibility code in system tests

* Remove six from setup.py

* Remove Py2.7 constraints file

* Update README

* respond to feedback

* remove kokoro presubmit for 2.7

* Update README.rst

Co-authored-by: cojenco <cathyo@google.com>

Co-authored-by: cojenco <cathyo@google.com>

README.rst

@@ -65,6 +65,9 @@ Unsupported Python Versions
 Python == 3.5: the last released version which supported Python 3.5 was
 ``google-cloud-storage 1.32.0``, released 2020-10-16.
 
+Python == 2.7: the last released version which supported Python 2.7 was
+``google-cloud-storage 1.44.0``, released 2022-01-05.
+
 Mac/Linux
 ^^^^^^^^^
 

google/cloud/storage/_helpers.py

@@ -19,11 +19,9 @@
 
 import base64
 from hashlib import md5
-from datetime import datetime
 import os
+from urllib.parse import urlsplit
 
-from six import string_types
-from six.moves.urllib.parse import urlsplit
 from google import resumable_media
 from google.cloud.storage.constants import _DEFAULT_TIMEOUT
 from google.cloud.storage.retry import DEFAULT_RETRY
@@ -453,20 +451,6 @@ def _base64_md5hash(buffer_object):
     return base64.b64encode(digest_bytes)
 
 
-def _convert_to_timestamp(value):
-    """Convert non-none datetime to timestamp.
-
-    :type value: :class:`datetime.datetime`
-    :param value: The datetime to convert.
-
-    :rtype: int
-    :returns: The timestamp.
-    """
-    utc_naive = value.replace(tzinfo=None) - value.utcoffset()
-    mtime = (utc_naive - datetime(1970, 1, 1)).total_seconds()
-    return mtime
-
-
 def _add_etag_match_headers(headers, **match_parameters):
     """Add generation match parameters into the given parameters list.
 
@@ -480,7 +464,7 @@ def _add_etag_match_headers(headers, **match_parameters):
         value = match_parameters.get(snakecase_name)
 
         if value is not None:
-            if isinstance(value, string_types):
+            if isinstance(value, str):
                 value = [value]
             headers[header_name] = ", ".join(value)
 

google/cloud/storage/_signing.py

@@ -20,7 +20,8 @@
 import hashlib
 import json
 
-import six
+import http
+import urllib
 
 import google.auth.credentials
 
@@ -110,15 +111,15 @@ def get_expiration_seconds_v2(expiration):
         micros = _helpers._microseconds_from_datetime(expiration)
         expiration = micros // 10 ** 6
 
-    if not isinstance(expiration, six.integer_types):
+    if not isinstance(expiration, int):
         raise TypeError(
             "Expected an integer timestamp, datetime, or "
             "timedelta. Got %s" % type(expiration)
         )
     return expiration
 
 
-_EXPIRATION_TYPES = six.integer_types + (datetime.datetime, datetime.timedelta)
+_EXPIRATION_TYPES = (int, datetime.datetime, datetime.timedelta)
 
 
 def get_expiration_seconds_v4(expiration):
@@ -142,7 +143,7 @@ def get_expiration_seconds_v4(expiration):
 
     now = NOW().replace(tzinfo=_helpers.UTC)
 
-    if isinstance(expiration, six.integer_types):
+    if isinstance(expiration, int):
         seconds = expiration
 
     if isinstance(expiration, datetime.datetime):
@@ -250,7 +251,7 @@ def canonicalize_v2(method, resource, query_parameters, headers):
         (key.lower(), value and value.strip() or "")
         for key, value in query_parameters.items()
     )
-    encoded_qp = six.moves.urllib.parse.urlencode(normalized_qp)
+    encoded_qp = urllib.parse.urlencode(normalized_qp)
     canonical_resource = "{}?{}".format(resource, encoded_qp)
     return _Canonical(method, canonical_resource, normalized_qp, headers)
 
@@ -410,7 +411,7 @@ def generate_signed_url_v2(
     return "{endpoint}{resource}?{querystring}".format(
         endpoint=api_access_endpoint,
         resource=resource,
-        querystring=six.moves.urllib.parse.urlencode(sorted_signed_query_params),
+        querystring=urllib.parse.urlencode(sorted_signed_query_params),
     )
 
 
@@ -563,7 +564,7 @@ def generate_signed_url_v4(
 
     header_names = [key.lower() for key in headers]
     if "host" not in header_names:
-        headers["Host"] = six.moves.urllib.parse.urlparse(api_access_endpoint).netloc
+        headers["Host"] = urllib.parse.urlparse(api_access_endpoint).netloc
 
     if method.upper() == "RESUMABLE":
         method = "POST"
@@ -686,7 +687,7 @@ def _sign_message(message, access_token, service_account_email):
     request = requests.Request()
     response = request(url=url, method=method, body=body, headers=headers)
 
-    if response.status != six.moves.http_client.OK:
+    if response.status != http.client.OK:
         raise exceptions.TransportError(
             "Error calling the IAM signBytes API: {}".format(response.data)
         )
@@ -723,4 +724,4 @@ def _quote_param(param):
     """
     if not isinstance(param, bytes):
         param = str(param)
-    return six.moves.urllib.parse.quote(param, safe="~")
+    return urllib.parse.quote(param, safe="~")

google/cloud/storage/batch.py

@@ -24,7 +24,6 @@
 import json
 
 import requests
-import six
 
 from google.cloud import _helpers
 from google.cloud import exceptions
@@ -65,13 +64,7 @@ def __init__(self, method, uri, headers, body):
         lines.append("")
         lines.append(body)
         payload = "\r\n".join(lines)
-        if six.PY2:
-            # email.message.Message is an old-style class, so we
-            # cannot use 'super()'.
-            MIMEApplication.__init__(self, payload, "http", encode_noop)
-        else:  # pragma: NO COVER  Python3
-            super_init = super(MIMEApplicationHTTP, self).__init__
-            super_init(payload, "http", encode_noop)
+        super().__init__(payload, "http", encode_noop)
 
 
 class _FutureDict(object):
@@ -219,11 +212,7 @@ def _prepare_batch_request(self):
             multi.attach(subrequest)
             timeout = _timeout
 
-        # The `email` package expects to deal with "native" strings
-        if six.PY2:  # pragma: NO COVER  Python3
-            buf = io.BytesIO()
-        else:
-            buf = io.StringIO()
+        buf = io.StringIO()
         generator = Generator(buf, False, 0)
         generator.flatten(multi)
         payload = buf.getvalue()
@@ -315,10 +304,7 @@ def _generate_faux_mime_message(parser, response):
         [b"Content-Type: ", content_type, b"\nMIME-Version: 1.0\n\n", response.content]
     )
 
-    if six.PY2:
-        return parser.parsestr(faux_message)
-    else:  # pragma: NO COVER  Python3
-        return parser.parsestr(faux_message.decode("utf-8"))
+    return parser.parsestr(faux_message.decode("utf-8"))
 
 
 def _unpack_batch_response(response):

google/cloud/storage/blob.py

@@ -35,15 +35,13 @@
 import mimetypes
 import os
 import re
+from urllib.parse import parse_qsl
+from urllib.parse import quote
+from urllib.parse import urlencode
+from urllib.parse import urlsplit
+from urllib.parse import urlunsplit
 import warnings
 
-import six
-from six.moves.urllib.parse import parse_qsl
-from six.moves.urllib.parse import quote
-from six.moves.urllib.parse import urlencode
-from six.moves.urllib.parse import urlsplit
-from six.moves.urllib.parse import urlunsplit
-
 from google import resumable_media
 from google.resumable_media.requests import ChunkedDownload
 from google.resumable_media.requests import Download
@@ -64,7 +62,6 @@
 from google.cloud.storage._helpers import _PropertyMixin
 from google.cloud.storage._helpers import _scalar_property
 from google.cloud.storage._helpers import _bucket_bound_hostname_url
-from google.cloud.storage._helpers import _convert_to_timestamp
 from google.cloud.storage._helpers import _raise_if_more_than_one_set
 from google.cloud.storage._helpers import _api_core_retry_to_resumable_media_retry
 from google.cloud.storage._signing import generate_signed_url_v2
@@ -1303,10 +1300,7 @@ def download_to_filename(
 
         updated = self.updated
         if updated is not None:
-            if six.PY2:
-                mtime = _convert_to_timestamp(updated)
-            else:
-                mtime = updated.timestamp()
+            mtime = updated.timestamp()
             os.utime(file_obj.name, (mtime, mtime))
 
     def download_as_bytes(

google/cloud/storage/bucket.py

@@ -18,11 +18,9 @@
 import copy
 import datetime
 import json
+from urllib.parse import urlsplit
 import warnings
 
-import six
-from six.moves.urllib.parse import urlsplit
-
 from google.api_core import datetime_helpers
 from google.cloud._helpers import _datetime_to_rfc3339
 from google.cloud._helpers import _NOW
@@ -1705,7 +1703,7 @@ def delete_blobs(
         for blob in blobs:
             try:
                 blob_name = blob
-                if not isinstance(blob_name, six.string_types):
+                if not isinstance(blob_name, str):
                     blob_name = blob.name
                 self.delete_blob(
                     blob_name,

google/cloud/storage/retry.py

@@ -20,19 +20,13 @@
 from google.auth import exceptions as auth_exceptions
 
 
-# ConnectionError is a built-in exception only in Python3 and not in Python2.
-try:
-    _RETRYABLE_STDLIB_TYPES = (ConnectionError,)
-except NameError:
-    _RETRYABLE_STDLIB_TYPES = ()
-
-
-_RETRYABLE_TYPES = _RETRYABLE_STDLIB_TYPES + (
+_RETRYABLE_TYPES = (
     api_exceptions.TooManyRequests,  # 429
     api_exceptions.InternalServerError,  # 500
     api_exceptions.BadGateway,  # 502
     api_exceptions.ServiceUnavailable,  # 503
     api_exceptions.GatewayTimeout,  # 504
+    ConnectionError,
     requests.ConnectionError,
     requests_exceptions.ChunkedEncodingError,
 )

noxfile.py

@@ -28,8 +28,8 @@
 BLACK_PATHS = ["docs", "google", "tests", "noxfile.py", "setup.py"]
 
 DEFAULT_PYTHON_VERSION = "3.8"
-SYSTEM_TEST_PYTHON_VERSIONS = ["2.7", "3.8"]
-UNIT_TEST_PYTHON_VERSIONS = ["2.7", "3.6", "3.7", "3.8", "3.9", "3.10"]
+SYSTEM_TEST_PYTHON_VERSIONS = ["3.8"]
+UNIT_TEST_PYTHON_VERSIONS = ["3.6", "3.7", "3.8", "3.9", "3.10"]
 CONFORMANCE_TEST_PYTHON_VERSIONS = ["3.8"]
 
 _DEFAULT_STORAGE_HOST = "https://storage.googleapis.com"

setup.py

@@ -28,19 +28,12 @@
 # 'Development Status :: 5 - Production/Stable'
 release_status = "Development Status :: 5 - Production/Stable"
 dependencies = [
-    "google-auth >= 1.25.0, < 2.0dev; python_version<'3.0'",
-    "google-auth >= 1.25.0, < 3.0dev; python_version>='3.6'",
-    "google-api-core >= 1.29.0, < 2.0dev; python_version<'3.0'",
-    "google-api-core >= 1.29.0, < 3.0dev; python_version>='3.6'",
-    "google-cloud-core >= 1.6.0, < 2.0dev; python_version<'3.0'",
-    "google-cloud-core >= 1.6.0, < 3.0dev; python_version>='3.6'",
-    "google-resumable-media >= 1.3.0, < 2.0dev; python_version<'3.0'",
-    "google-resumable-media >= 1.3.0, < 3.0dev; python_version>='3.6'",
+    "google-auth >= 1.25.0, < 3.0dev",
+    "google-api-core >= 1.29.0, < 3.0dev",
+    "google-cloud-core >= 1.6.0, < 3.0dev",
+    "google-resumable-media >= 1.3.0",
     "requests >= 2.18.0, < 3.0.0dev",
-    "protobuf < 3.18.0; python_version<'3.0'",
-    "protobuf; python_version>='3.6'",
-    "googleapis-common-protos < 1.53.0; python_version<'3.0'",
-    "six",
+    "protobuf",
 ]
 extras = {}
 
@@ -84,8 +77,6 @@
         "Intended Audience :: Developers",
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
-        "Programming Language :: Python :: 2",
-        "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
@@ -100,7 +91,7 @@
     namespace_packages=namespaces,
     install_requires=dependencies,
     extras_require=extras,
-    python_requires=">=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,!=3.5.*",
+    python_requires=">=3.6",
     include_package_data=True,
     zip_safe=False,
 )

tests/system/_helpers.py

@@ -14,8 +14,6 @@
 
 import os
 
-import six
-
 from google.api_core import exceptions
 
 from test_utils.retry import RetryErrors
@@ -27,17 +25,7 @@
 retry_429_503 = RetryErrors(
     [exceptions.TooManyRequests, exceptions.ServiceUnavailable], max_tries=10
 )
-
-# Work around https://github.com/googleapis/python-test-utils/issues/36
-if six.PY3:
-    retry_failures = RetryErrors(AssertionError)
-else:
-
-    def retry_failures(decorated):  # no-op
-        wrapped = RetryErrors(AssertionError)(decorated)
-        wrapped.__wrapped__ = decorated
-        return wrapped
-
+retry_failures = RetryErrors(AssertionError)
 
 user_project = os.environ.get("GOOGLE_CLOUD_TESTS_USER_PROJECT")
 testing_mtls = os.getenv("GOOGLE_API_USE_CLIENT_CERTIFICATE") == "true"

tests/system/test_blob.py

@@ -20,7 +20,6 @@
 import warnings
 
 import pytest
-import six
 import mock
 
 from google import resumable_media
@@ -33,7 +32,7 @@
 
 def _check_blob_hash(blob, info):
     md5_hash = blob.md5_hash
-    if not isinstance(md5_hash, six.binary_type):
+    if not isinstance(md5_hash, bytes):
         md5_hash = md5_hash.encode("utf-8")
 
     assert md5_hash == info["hash"]