mercurial/urllibcompat.py

wireprotov1peer: simplify the way batchable rpcs are defined

The scheme with futures/generator is confusing due to the way
communication is done by side effects, especially with two different
"future" objects. Just returning a request and a function to read the
response is easier to understand.

There are tests failures with the largefiles extension due to it
aliasing one rpc to another one, which gets fixed in the next commit.

Differential Revision: https://phab.mercurial-scm.org/D11211

# urllibcompat.py - adapters to ease using urllib2 on Py2 and urllib on Py3
#
# Copyright 2017 Google, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import

from .pycompat import getattr
from . import pycompat

_sysstr = pycompat.sysstr


class _pycompatstub(object):
    def __init__(self):
        self._aliases = {}

    def _registeraliases(self, origin, items):
        """Add items that will be populated at the first access"""
        items = map(_sysstr, items)
        self._aliases.update(
            (item.replace('_', '').lower(), (origin, item)) for item in items
        )

    def _registeralias(self, origin, attr, name):
        """Alias ``origin``.``attr`` as ``name``"""
        self._aliases[_sysstr(name)] = (origin, _sysstr(attr))

    def __getattr__(self, name):
        try:
            origin, item = self._aliases[name]
        except KeyError:
            raise AttributeError(name)
        self.__dict__[name] = obj = getattr(origin, item)
        return obj


httpserver = _pycompatstub()
urlreq = _pycompatstub()
urlerr = _pycompatstub()

if pycompat.ispy3:
    import urllib.parse

    urlreq._registeraliases(
        urllib.parse,
        (
            b"splitattr",
            b"splitpasswd",
            b"splitport",
            b"splituser",
            b"urlparse",
            b"urlunparse",
        ),
    )
    urlreq._registeralias(urllib.parse, b"parse_qs", b"parseqs")
    urlreq._registeralias(urllib.parse, b"parse_qsl", b"parseqsl")
    urlreq._registeralias(urllib.parse, b"unquote_to_bytes", b"unquote")
    import urllib.request

    urlreq._registeraliases(
        urllib.request,
        (
            b"AbstractHTTPHandler",
            b"BaseHandler",
            b"build_opener",
            b"FileHandler",
            b"FTPHandler",
            b"ftpwrapper",
            b"HTTPHandler",
            b"HTTPSHandler",
            b"install_opener",
            b"pathname2url",
            b"HTTPBasicAuthHandler",
            b"HTTPDigestAuthHandler",
            b"HTTPPasswordMgrWithDefaultRealm",
            b"ProxyHandler",
            b"Request",
            b"url2pathname",
            b"urlopen",
        ),
    )
    import urllib.response

    urlreq._registeraliases(
        urllib.response,
        (
            b"addclosehook",
            b"addinfourl",
        ),
    )
    import urllib.error

    urlerr._registeraliases(
        urllib.error,
        (
            b"HTTPError",
            b"URLError",
        ),
    )
    import http.server

    httpserver._registeraliases(
        http.server,
        (
            b"HTTPServer",
            b"BaseHTTPRequestHandler",
            b"SimpleHTTPRequestHandler",
            b"CGIHTTPRequestHandler",
        ),
    )

    # urllib.parse.quote() accepts both str and bytes, decodes bytes
    # (if necessary), and returns str. This is wonky. We provide a custom
    # implementation that only accepts bytes and emits bytes.
    def quote(s, safe='/'):
        # bytestr has an __iter__ that emits characters. quote_from_bytes()
        # does an iteration and expects ints. We coerce to bytes to appease it.
        if isinstance(s, pycompat.bytestr):
            s = bytes(s)
        s = urllib.parse.quote_from_bytes(s, safe=safe)
        return s.encode('ascii', 'strict')

    # urllib.parse.urlencode() returns str. We use this function to make
    # sure we return bytes.
    def urlencode(query, doseq=False):
        s = urllib.parse.urlencode(query, doseq=doseq)
        return s.encode('ascii')

    urlreq.quote = quote
    urlreq.urlencode = urlencode

    def getfullurl(req):
        return req.full_url

    def gethost(req):
        return req.host

    def getselector(req):
        return req.selector

    def getdata(req):
        return req.data

    def hasdata(req):
        return req.data is not None


else:
    # pytype: disable=import-error
    import BaseHTTPServer
    import CGIHTTPServer
    import SimpleHTTPServer
    import urllib2
    import urllib
    import urlparse

    # pytype: enable=import-error

    urlreq._registeraliases(
        urllib,
        (
            b"addclosehook",
            b"addinfourl",
            b"ftpwrapper",
            b"pathname2url",
            b"quote",
            b"splitattr",
            b"splitpasswd",
            b"splitport",
            b"splituser",
            b"unquote",
            b"url2pathname",
            b"urlencode",
        ),
    )
    urlreq._registeraliases(
        urllib2,
        (
            b"AbstractHTTPHandler",
            b"BaseHandler",
            b"build_opener",
            b"FileHandler",
            b"FTPHandler",
            b"HTTPBasicAuthHandler",
            b"HTTPDigestAuthHandler",
            b"HTTPHandler",
            b"HTTPPasswordMgrWithDefaultRealm",
            b"HTTPSHandler",
            b"install_opener",
            b"ProxyHandler",
            b"Request",
            b"urlopen",
        ),
    )
    urlreq._registeraliases(
        urlparse,
        (
            b"urlparse",
            b"urlunparse",
        ),
    )
    urlreq._registeralias(urlparse, b"parse_qs", b"parseqs")
    urlreq._registeralias(urlparse, b"parse_qsl", b"parseqsl")
    urlerr._registeraliases(
        urllib2,
        (
            b"HTTPError",
            b"URLError",
        ),
    )
    httpserver._registeraliases(
        BaseHTTPServer,
        (
            b"HTTPServer",
            b"BaseHTTPRequestHandler",
        ),
    )
    httpserver._registeraliases(
        SimpleHTTPServer, (b"SimpleHTTPRequestHandler",)
    )
    httpserver._registeraliases(CGIHTTPServer, (b"CGIHTTPRequestHandler",))

    def gethost(req):
        return req.get_host()

    def getselector(req):
        return req.get_selector()

    def getfullurl(req):
        return req.get_full_url()

    def getdata(req):
        return req.get_data()

    def hasdata(req):
        return req.has_data()