Drop Python 2 support

closes release-engineering#158

.travis.yml

@@ -1,8 +1,6 @@
 language: python
 matrix:
     include:
-        - python: "2.7"
-          env: TOXENV=py27
         - python: "3.6"
           env: TOXENV=py36
         - python: "3.7"

README.md

@@ -16,13 +16,6 @@ http://productmd.readthedocs.io/en/latest/
 Building
 --------
 
-### Build requires
-
-* Six: Python 2 and 3 Compatibility Library
- * `pip install six`
- * Fedora: `dnf install python-six python3-six`
-
-
 ### Build
 
 To see all options run:

productmd/__init__.py

@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 # Copyright (C) 2015  Red Hat, Inc.
 #
 # This library is free software; you can redistribute it and/or

productmd/common.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # pylint: disable=super-on-old-class
 
 
@@ -29,14 +28,15 @@
 import sys
 import re
 import json
+import http
 import codecs
 import contextlib
 import ssl
 import warnings
+import urllib
 
-import six
-from six.moves.configparser import ConfigParser
-
+from configparser import ConfigParser
+from io import StringIO
 
 VERSION = (1, 2)
 
@@ -165,7 +165,7 @@ def _urlopen(path):
         # Older Python versions (<2.7.9) do not support it. In those cases the
         # ssl module will not have the method to create the context.
         kwargs['context'] = ssl._create_unverified_context()
-    return six.moves.urllib.request.urlopen(path, **kwargs)
+    return urllib.request.urlopen(path, **kwargs)
 
 
 @contextlib.contextmanager
@@ -178,7 +178,7 @@ def open_file_obj(f, mode="r"):
     :param mode: how to open the file
     :type mode: string
     """
-    if isinstance(f, six.string_types):
+    if isinstance(f, str):
         if f.startswith(("http://", "https://", "ftp://")):
             file_obj = _urlopen(f)
             yield file_obj
@@ -195,13 +195,13 @@ def _file_exists(path):
         try:
             file_obj = _urlopen(path)
             file_obj.close()
-        except six.moves.urllib.error.HTTPError:
+        except urllib.error.HTTPError:
             return False
         return True
     return os.path.exists(path)
 
 
-class MetadataBase(object):
+class MetadataBase:
     def _assert_type(self, field, expected_types):
         value = getattr(self, field)
         for atype in expected_types:
@@ -269,7 +269,7 @@ def loads(self, s):
         :param s: input data
         :type s: str
         """
-        io = six.StringIO()
+        io = StringIO()
         io.write(s)
         io.seek(0)
         self.load(io)
@@ -294,7 +294,7 @@ def dumps(self):
 
         :rtype: str
         """
-        io = six.StringIO()
+        io = StringIO()
         self.dump(io)
         io.seek(0)
         return io.read()
@@ -306,12 +306,10 @@ def parse_file(self, f):
                 f.seek(0)
         elif hasattr(f, "seek"):
             f.seek(0)
-        if six.PY3 and isinstance(f, six.moves.http_client.HTTPResponse):
+        if isinstance(f, http.client.HTTPResponse):
             # HTTPResponse needs special handling in py3
             reader = codecs.getreader("utf-8")
             parser = json.load(reader(f))
-        else:
-            parser = json.load(f)
         return parser
 
     def build_file(self, parser, f):
@@ -343,7 +341,7 @@ def __init__(self, parent, metadata_type):
         self.metadata_type = metadata_type
 
     def _validate_version(self):
-        self._assert_type("version", six.string_types)
+        self._assert_type("version", [str])
         self._assert_matches_re("version", [r"^\d+\.\d+$"])
 
     @property
@@ -550,7 +548,7 @@ def __init__(self, *args, **kwargs):
             ConfigParser.__init__(self, *args, **kwargs)
         else:
             kwargs["dict_type"] = SortedDict
-            super(SortedConfigParser, self).__init__(*args, **kwargs)
+            super().__init__(*args, **kwargs)
         self.seen = set()
 
     def optionxform(self, optionstr):
@@ -566,4 +564,4 @@ def option_lookup(self, section_option_list, default=None):
     def read_file(self, *args, **kwargs):
         if sys.version_info[0] == 2:
             return self.readfp(*args, **kwargs)
-        return super(SortedConfigParser, self).read_file(*args, **kwargs)
+        return super().read_file(*args, **kwargs)

productmd/compose.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-
-
 # Copyright (C) 2015  Red Hat, Inc.
 #
 # This library is free software; you can redistribute it and/or
@@ -49,7 +46,7 @@
 )
 
 
-class Compose(object):
+class Compose:
     """
     This class provides easy access to compose metadata.
 

productmd/composeinfo.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-
-
 # Copyright (C) 2015  Red Hat, Inc.
 #
 # This library is free software; you can redistribute it and/or
@@ -36,8 +33,6 @@
 import productmd.common
 from productmd.common import Header, RELEASE_VERSION_RE
 
-import six
-
 
 __all__ = (
     "ComposeInfo",
@@ -47,9 +42,8 @@
 )
 
 
-if six.PY3:
-    def cmp(a, b):
-        return (a > b) - (a < b)
+def cmp(a, b):
+    return (a > b) - (a < b)
 
 
 # order matters - used in __cmp__
@@ -121,7 +115,7 @@ class ComposeInfo(productmd.common.MetadataBase):
     """
 
     def __init__(self):
-        super(ComposeInfo, self).__init__()
+        super().__init__()
 
         self.header = Header(self, "productmd.composeinfo")     #: (:class:`.Header`) -- Metadata header
         self.compose = Compose(self)            #: (:class:`.Compose`) -- Compose details
@@ -265,7 +259,7 @@ class Compose(productmd.common.MetadataBase):
     """
 
     def __init__(self, metadata):
-        super(Compose, self).__init__()
+        super().__init__()
         self._section = "compose"
         self._metadata = metadata
         self.id = None
@@ -293,22 +287,22 @@ def __cmp__(self, other):
         return 0
 
     def _validate_id(self):
-        self._assert_type("id", list(six.string_types))
+        self._assert_type("id", [str])
         self._assert_not_blank("id")
         self._assert_matches_re("id", [r".*\d{8}(\.nightly|\.n|\.ci|\.test|\.t)?(\.\d+)?"])
 
     def _validate_date(self):
-        self._assert_type("date", list(six.string_types))
+        self._assert_type("date", [str])
         self._assert_matches_re("date", [r"^\d{8}$"])
 
     def _validate_type(self):
         self._assert_value("type", COMPOSE_TYPES)
 
     def _validate_respin(self):
-        self._assert_type("respin", list(six.integer_types))
+        self._assert_type("respin", [int])
 
     def _validate_label(self):
-        self._assert_type("label", [type(None)] + list(six.string_types))
+        self._assert_type("label", [type(None), str])
         verify_label(self.label)
 
     def _validate_final(self):
@@ -397,7 +391,7 @@ class BaseProduct(productmd.common.MetadataBase):
     """
 
     def __init__(self, metadata):
-        super(BaseProduct, self).__init__()
+        super().__init__()
         self._section = "base_product"
         self._metadata = metadata
         self.name = None        #: (*str*) -- Product name, for example: "Fedora", "Red Hat Enterprise Linux"
@@ -421,20 +415,20 @@ def __str__(self):
         return "%s-%s" % (self.short, self.version)
 
     def _validate_name(self):
-        self._assert_type("name", list(six.string_types))
+        self._assert_type("name", [str])
 
     def _validate_version(self):
         """If the version starts with a digit, it must be a sematic-versioning
         style string.
         """
-        self._assert_type("version", list(six.string_types))
+        self._assert_type("version", [str])
         self._assert_matches_re("version", [RELEASE_VERSION_RE])
 
     def _validate_short(self):
-        self._assert_type("short", list(six.string_types))
+        self._assert_type("short", [str])
 
     def _validate_type(self):
-        self._assert_type("type", list(six.string_types))
+        self._assert_type("type", [str])
         self._assert_value("type", productmd.common.RELEASE_TYPES)
 
     @property
@@ -478,7 +472,7 @@ class Release(BaseProduct):
     """
 
     def __init__(self, metadata):
-        super(Release, self).__init__(metadata)
+        super().__init__(metadata)
         self._section = "release"
 
         self.name = None                #: (*str*) -- Release name, for example: "Fedora", "Red Hat Enterprise Linux"
@@ -494,7 +488,7 @@ def __cmp__(self, other):
         return BaseProduct.__cmp__(self, other)
 
     def _validate_type(self):
-        self._assert_type("type", list(six.string_types))
+        self._assert_type("type", [str])
         self._assert_value("type", productmd.common.RELEASE_TYPES)
 
     def _validate_is_layered(self):
@@ -539,7 +533,7 @@ def deserialize_1_0(self, data):
 
 class VariantBase(productmd.common.MetadataBase):
     def __init__(self, metadata):
-        super(VariantBase, self).__init__()
+        super().__init__()
         self._metadata = metadata
         self.parent = None
         self.variants = {}
@@ -548,7 +542,7 @@ def __repr__(self):
         if hasattr(self, "compose"):
             return u'<%s:%s>' % (self.__class__.__name__, self._metadata.compose.id)
         else:
-            return super(VariantBase, self).__repr__()
+            return super().__repr__()
 
     def __getitem__(self, name):
         # There can be exceptions, like $variant-optional on top-level,
@@ -625,7 +619,7 @@ def get_variants(self, arch=None, types=None, recursive=False):
         if "self" in types:
             result.append(self)
 
-        for variant in six.itervalues(self.variants):
+        for variant in self.variants.values():
             if types and variant.type not in types:
                 continue
             if arch and arch not in variant.arches.union(["src"]):
@@ -642,8 +636,9 @@ class Variants(VariantBase):
     """
     This class is a container for compose variants.
     """
+
     def __init__(self, metadata):
-        super(Variants, self).__init__(metadata)
+        super().__init__(metadata)
         self._section = "variants"
 
     def serialize(self, data):
@@ -813,7 +808,7 @@ def __repr__(self):
         return u'<%s:%s>' % (self.__class__.__name__, self.uid)
 
     def _validate_id(self):
-        self._assert_type("id", list(six.string_types))
+        self._assert_type("id", [str])
         self._assert_matches_re("id", [r"^[a-zA-Z0-9]+$"])
 
     def _validate_uid(self):
@@ -828,7 +823,7 @@ def _validate_uid(self):
             raise ValueError("UID '%s' doesn't align with parent UID '%s'" % (self.uid, uid))
 
     def _validate_name(self):
-        self._assert_type("name", list(six.string_types))
+        self._assert_type("name", [str])
         self._assert_not_blank("name")
 
     def _validate_type(self):

productmd/discinfo.py

@@ -41,7 +41,7 @@ class DiscInfo(productmd.common.MetadataBase):
     """
 
     def __init__(self):
-        super(DiscInfo, self).__init__()
+        super().__init__()
         self.timestamp = None           #: Timestamp in float format
         self.description = None         #: Release description, for example: Fedora 20
         self.arch = None                #: Media architecture, for example: x86_64

productmd/extra_files.py

@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 # Copyright (C) 2019  Red Hat, Inc.
 #
 # This library is free software; you can redistribute it and/or
@@ -28,7 +26,7 @@
 
 class ExtraFiles(productmd.common.MetadataBase):
     def __init__(self):
-        super(ExtraFiles, self).__init__()
+        super().__init__()
         self.header = Header(self, "productmd.extra_files")
         self.compose = Compose(self)
         self.extra_files = {}