Revise Python versions; upgrade Pylint and employ it more

Python 2 will reach "end of life" by the end of the year.
Already now it's increasingly a hassle to support.
For example, there seems to be no version of Pylint/Astroid
that would work under both Python 2.7 and Python 3.7.

.isort.cfg

@@ -1,9 +1,5 @@
 [isort]
 
-# Python 2.x/3.x standard library shims should be intermingled
-# with the actual standard library.
-known_standard_library=six.moves,httpolice.util.moves
-
 # ``from ... import`` should be intermingled with ``import ...``.
 force_sort_within_sections=true
 

.travis.yml

@@ -1,22 +1,26 @@
 language: python
-dist: trusty
+dist: xenial
 sudo: false
 
 addons:
     apt:
         packages:
             - xmlstarlet
 
-python:
-    - "2.7"
-    - "pypy"
-    - "3.4"
-    - "3.5"
-    - "3.6"
-
-env:
-    - REQUIRES=minimum
-    - REQUIRES=normal
+matrix:
+    include:
+        - python: "3.4"
+          env: REQUIRES=normal
+        - python: "3.5"
+          env: REQUIRES=normal
+        - python: "pypy3.5"
+          env: REQUIRES=normal
+        - python: "3.6"
+          env: REQUIRES=normal
+        - python: "3.6"
+          env: REQUIRES=minimum
+        - python: "3.7"
+          env: REQUIRES=normal
 
 install:
     - if [ "$REQUIRES" = minimum ]; then tools/minimum_requires.sh; fi
@@ -33,7 +37,7 @@ script:
 
     # Basic stuff.
     - python setup.py check --strict --restructuredtext
-    - tools/pylint_all.sh -j 2
+    - tools/pylint_all.sh -j 2 --reports=no --score=no
     - pytest
 
     # Although the main docs (``doc/``) are processed by Read the Docs,
@@ -57,7 +61,7 @@ deploy:
     on:
         tags: true
         # Only release from one of the environments.
-        python: "3.5"
+        python: "3.6"
         condition: $REQUIRES = normal
     provider: pypi
     user: vfaronov

CHANGELOG.rst

@@ -2,6 +2,12 @@ History of changes
 ==================
 
 
+Unreleased
+~~~~~~~~~~
+- Dropped Python 2 support. If you need it, use the older versions.
+- HTTPolice no longer requires `six` nor `singledispatch`.
+
+
 0.7.0 - 2018-03-31
 ~~~~~~~~~~~~~~~~~~
 

HACKING.rst

@@ -5,8 +5,8 @@ Development environment
 ~~~~~~~~~~~~~~~~~~~~~~~
 Set up::
 
-  $ virtualenv /path/to/env
-  $ source /path/to/env/bin/activate
+  $ python3 -m venv /path/to/env
+  $ . /path/to/env/bin/activate
   $ pip install -e .
   $ pip install -r tools/requirements.txt
   $ pip install ...    # any extra tools you like to have

README.rst

@@ -21,9 +21,8 @@ __ https://httpolice.readthedocs.io/page/showcase.html
 
 As a command-line tool, it can read `HAR files`__ or raw HTTP/1.x TCP streams.
 It can integrate with `mitmproxy`__ for TLS-encrypted and HTTP/2 traffic.
-Or you can use it as a Python library (for Python 2.7 and 3.4+),
-with optional `Django`__ integration.
-There is also a third-party `Chrome extension`__.
+Or you can use it as a Python (3.4+) library.
+There is a `Django`__ integration package and a third-party `Chrome extension`__.
 
 __ https://en.wikipedia.org/wiki/.har
 __ https://mitmproxy.org/

doc/install.rst

@@ -3,8 +3,8 @@ Installation
 
 .. highlight:: console
 
-HTTPolice is a Python package that requires `Python`__ 2.7 or 3.4+.
-`PyPy`__ is also supported (reasonably recent versions; 5.3.1 is OK).
+HTTPolice is a Python package that requires `Python`__ 3.4+.
+`PyPy`__ is also supported.
 
 __ https://www.python.org/
 __ http://pypy.org/

doc/quickstart.rst

@@ -7,10 +7,9 @@ Quickstart
 Installation
 ------------
 
-HTTPolice is a Python package that can be installed with pip
-(on Python 2.7 or 3.4+)::
+HTTPolice is a Python package that can be installed with pip (on Python 3.4+)::
 
-  $ pip install HTTPolice
+  $ pip3 install HTTPolice
 
 If you’re not familiar with pip, check the manual’s :doc:`install` section.
 

httpolice/blackboard.py

@@ -31,7 +31,7 @@ def severity(self):
         return self.notice.severity
 
 
-class Blackboard(object):
+class Blackboard:
 
     """Shared state that various parts of the code can "write upon".
 

httpolice/citation.py

@@ -1,10 +1,6 @@
 # -*- coding: utf-8; -*-
 
-import six
-
-
-@six.python_2_unicode_compatible
-class Citation(object):
+class Citation:
 
     """A reference to a relevant document."""
 
@@ -42,8 +38,8 @@ class RFC(Citation):
     def __init__(self, num, section=None, appendix=None, errata=None):
         assert bool(section) + bool(appendix) + bool(errata) <= 1
         self.num = num = int(num)
-        self.section = section = six.text_type(section) if section else None
-        self.appendix = appendix = six.text_type(appendix) if appendix else None
+        self.section = section = str(section) if section else None
+        self.appendix = appendix = str(appendix) if appendix else None
         self.errata = errata = int(errata) if errata else None
         title = u'RFC %d' % num         # no-break space
         if errata:

httpolice/cli.py

@@ -11,7 +11,6 @@
 from httpolice import inputs, reports
 from httpolice.exchange import check_exchange
 from httpolice.notice import Severity
-from httpolice.util.text import stdio_as_bytes
 
 
 def parse_args(argv):
@@ -52,16 +51,15 @@ def generate_exchanges():
             yield exch
 
     try:
-        # We can't use stdout opened as text (as in Python 3)
-        # because it may not be UTF-8 (especially on Windows).
+        # Can't use stdout as text because it may not be UTF-8 (on Windows).
         # Our HTML reports are meant for redirection
         # and are always UTF-8, which is declared in ``meta``.
         # As for text reports, they are mostly ASCII,
         # but when they do contain a non-ASCII character
         # (perhaps from pieces of input data),
         # we don't want to trip over Unicode errors.
         # So we encode all text into UTF-8 and write directly as bytes.
-        report(generate_exchanges(), stdio_as_bytes(stdout))
+        report(generate_exchanges(), stdout.buffer)
     except (EnvironmentError, inputs.InputError) as exc:
         if args.full_traceback:
             traceback.print_exc(file=stderr)

httpolice/framing1.py

@@ -268,7 +268,7 @@ def _decode_transfer_coding(msg, coding):
         # The outermost chunked has already been peeled off at this point.
         msg.complain(1002)
         msg.body = Unavailable(msg.body)
-    elif coding == tc.gzip or coding == tc.x_gzip:
+    elif coding in [tc.gzip, tc.x_gzip]:
         try:
             msg.body = decode_gzip(msg.body)
         except Exception as e:
@@ -307,13 +307,12 @@ def _parse_chunk(stream, data):
                 raise stream.error(pos)
         if size == 0:
             return False
-        elif size + current_size > MAX_BODY_SIZE:
+        if size + current_size > MAX_BODY_SIZE:
             stream.sane = False
             raise BodyTooLongError(size + current_size, MAX_BODY_SIZE)
-        else:
-            data.append(stream.read(size))
-            stream.readlineend()
-            return True
+        data.append(stream.read(size))
+        stream.readlineend()
+        return True
 
 
 def _parse_chunked(msg, stream):

httpolice/header.py

@@ -19,8 +19,6 @@
 import operator
 import sys
 
-import six
-
 from httpolice import known
 from httpolice.known import HeaderRule, h
 from httpolice.parse import parse
@@ -29,7 +27,7 @@
 from httpolice.util.data import duplicates
 
 
-class HeadersView(object):
+class HeadersView:
 
     """Wraps all headers of a single message, exposing them as attributes."""
 
@@ -40,7 +38,7 @@ def special_case(cls, view_cls):
         assert view_cls.name not in cls.special_cases
         cls.special_cases[view_cls.name] = view_cls
         return view_cls
-        
+
     def __init__(self, message):
         self._message = message
         self._cache = {}
@@ -100,7 +98,7 @@ def clearly(self, predicate):
         return set(name for name in self.names if predicate(name))
 
 
-class HeaderView(object):
+class HeaderView:
 
     """Wraps all headers with a particular name in a given message.
 
@@ -165,7 +163,7 @@ def _check_quoted_delims(self, entry, parsed):
         comma, semicolon = known.header.bad_quoted_delims(self.name)
         if comma or semicolon:
             def check(v):
-                if isinstance(v, six.text_type):
+                if isinstance(v, str):
                     if comma and u',' in v:
                         self.message.complain(1299, entry=entry)
                     if semicolon and u';' in v:
@@ -222,7 +220,6 @@ def __contains__(self, other):
         # ignoring its parameters.
         # This is handled by :meth:`Parametrized.__eq__`,
         # but it's only invoked when the `Parametrized` is on the left side.
-        # pylint: disable=not-an-iterable
         return any(val == other for val in self)
 
     def _compare(self, other, op):
@@ -246,8 +243,7 @@ def _compare(self, other, op):
 
         if isinstance(other, HeaderView):
             return NotImplemented
-        else:
-            return self.is_okay and okay(other) and op(self.value, other)
+        return self.is_okay and okay(other) and op(self.value, other)
 
     def __lt__(self, other):
         return self._compare(other, operator.lt)
@@ -328,7 +324,6 @@ def _parse(self):
         self._entries = entries
 
     def __iter__(self):
-        # pylint: disable=not-an-iterable
         return iter(v for v in self.value if okay(v))
 
 

httpolice/helpers.py

@@ -2,8 +2,6 @@
 
 """Functions that may be useful for integrating with HTTPolice."""
 
-import six
-
 from httpolice.util.text import force_bytes, force_unicode
 
 
@@ -67,6 +65,6 @@ def _header_name_from_cgi(cgi_name):
 
 
 def _header_value_from_cgi(value):
-    if not isinstance(value, (six.text_type, bytes)):
+    if not isinstance(value, (str, bytes)):
         value = str(value)
     return force_bytes(value)

httpolice/inputs/har.py

@@ -3,10 +3,8 @@
 import base64
 import io
 import json
-from six.moves.urllib.parse import urlparse  # pylint: disable=import-error
 import re
-
-import six
+from urllib.parse import urlparse
 
 from httpolice import framing1
 from httpolice.exchange import Exchange
@@ -30,18 +28,14 @@ def har_input(paths):
             try:
                 data = json.load(f)
             except ValueError as exc:
-                six.raise_from(
-                    InputError(u'%s: bad HAR file: %s' % (path, exc)),
-                    exc)
+                raise InputError('%s: bad HAR file: %s' % (path, exc)) from exc
             try:
                 creator = CreatorInfo(data['log']['creator'])
                 for entry in data['log']['entries']:
                     yield _process_entry(entry, creator, path)
             except (TypeError, KeyError) as exc:
-                six.raise_from(
-                    InputError(u'%s: cannot understand HAR file: %r' %
-                               (path, exc)),
-                    exc)
+                raise InputError('%s: cannot understand HAR file: %r' %
+                                 (path, exc)) from exc
 
 
 def _process_entry(data, creator, path):

httpolice/inputs/streams.py

@@ -7,8 +7,6 @@
 import os
 import re
 
-import six
-
 from httpolice.exchange import complaint_box
 from httpolice.framing1 import parse_streams
 from httpolice.inputs.common import InputError
@@ -284,7 +282,7 @@ def _rearrange_by_time(sequences):
         (time, exchange) = position[i]
         if exchange is None:
             # Start iterating over this sequence.
-            exchange = next(sequences[i][0])
+            exchange = next(sequences[i][0], None)
             new_time = _exchange_time(exchange, time)
             if time is None or new_time > time:
                 # So this sequence actually starts at a later time than
@@ -317,22 +315,20 @@ def _exchange_time(exchange, hint):
             if resp.headers.age.is_okay:
                 return (resp.headers.date.value +
                         timedelta(seconds=resp.headers.age.value))
-            else:
-                return resp.headers.date.value
+            return resp.headers.date.value
     return hint
 
 
 def _sniff_direction(path1, path2):                 # pragma: no cover
     if path1 and _sniff_outbound(path1):
         return (path2, path1)
-    elif path2 and _sniff_outbound(path2):
+    if path2 and _sniff_outbound(path2):
         return (path1, path2)
-    elif path1 and _sniff_inbound(path1):
+    if path1 and _sniff_inbound(path1):
         return (path1, path2)
-    elif path2 and _sniff_inbound(path2):
+    if path2 and _sniff_inbound(path2):
         return (path2, path1)
-    else:
-        return None
+    return None
 
 
 def _sniff_outbound(path):
@@ -372,7 +368,7 @@ def parse_combined(path):
     try:
         preamble = preamble.decode('utf-8')
     except UnicodeError as exc:     # pragma: no cover
-        six.raise_from(InputError(u'%s: invalid UTF-8 in preamble' % path), exc)
+        raise InputError(u'%s: invalid UTF-8 in preamble' % path) from exc
     parts2 = rest.split(b'======== BEGIN OUTBOUND STREAM ========\r\n', 1)
     if len(parts2) != 2:            # pragma: no cover
         raise InputError(u'%s: bad combined file: no outbound marker' % path)