helpers.py

#VERSION: 1.43

# Author:
#  Christophe DUMEZ (chris@qbittorrent.org)

# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#    * Redistributions of source code must retain the above copyright notice,
#      this list of conditions and the following disclaimer.
#    * Redistributions in binary form must reproduce the above copyright
#      notice, this list of conditions and the following disclaimer in the
#      documentation and/or other materials provided with the distribution.
#    * Neither the name of the author nor the names of its contributors may be
#      used to endorse or promote products derived from this software without
#      specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

import gzip
import html.entities
import io
import os
import re
import socket
import socks
import tempfile
import urllib.error
import urllib.parse
import urllib.request

# Some sites blocks default python User-agent
user_agent = 'Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0'
headers = {'User-Agent': user_agent}
# SOCKS5 Proxy support
if "sock_proxy" in os.environ and len(os.environ["sock_proxy"].strip()) > 0:
    proxy_str = os.environ["sock_proxy"].strip()
    m = re.match(r"^(?:(?P<username>[^:]+):(?P<password>[^@]+)@)?(?P<host>[^:]+):(?P<port>\w+)$",
                 proxy_str)
    if m is not None:
        socks.setdefaultproxy(socks.PROXY_TYPE_SOCKS5, m.group('host'),
                              int(m.group('port')), True, m.group('username'), m.group('password'))
        socket.socket = socks.socksocket


def htmlentitydecode(s):
    # First convert alpha entities (such as &eacute;)
    # (Inspired from http://mail.python.org/pipermail/python-list/2007-June/443813.html)
    def entity2char(m):
        entity = m.group(1)
        if entity in html.entities.name2codepoint:
            return chr(html.entities.name2codepoint[entity])
        return " "  # Unknown entity: We replace with a space.
    t = re.sub('&(%s);' % '|'.join(html.entities.name2codepoint), entity2char, s)

    # Then convert numerical entities (such as &#233;)
    t = re.sub(r'&#(\d+);', lambda x: chr(int(x.group(1))), t)

    # Then convert hexa entities (such as &#x00E9;)
    return re.sub(r'&#x(\w+);', lambda x: chr(int(x.group(1), 16)), t)


def retrieve_url(url):
    """ Return the content of the url page as a string """
    req = urllib.request.Request(url, headers=headers)
    try:
        response = urllib.request.urlopen(req)
    except urllib.error.URLError as errno:
        print(" ".join(("Connection error:", str(errno.reason))))
        return ""
    dat = response.read()
    # Check if it is gzipped
    if dat[:2] == b'\x1f\x8b':
        # Data is gzip encoded, decode it
        compressedstream = io.BytesIO(dat)
        gzipper = gzip.GzipFile(fileobj=compressedstream)
        extracted_data = gzipper.read()
        dat = extracted_data
    info = response.info()
    charset = 'utf-8'
    try:
        ignore, charset = info['Content-Type'].split('charset=')
    except Exception:
        pass
    dat = dat.decode(charset, 'replace')
    dat = htmlentitydecode(dat)
    # return dat.encode('utf-8', 'replace')
    return dat


def download_file(url, referer=None):
    """ Download file at url and write it to a file, return the path to the file and the url """
    file, path = tempfile.mkstemp()
    file = os.fdopen(file, "wb")
    # Download url
    req = urllib.request.Request(url, headers=headers)
    if referer is not None:
        req.add_header('referer', referer)
    response = urllib.request.urlopen(req)
    dat = response.read()
    # Check if it is gzipped
    if dat[:2] == b'\x1f\x8b':
        # Data is gzip encoded, decode it
        compressedstream = io.BytesIO(dat)
        gzipper = gzip.GzipFile(fileobj=compressedstream)
        extracted_data = gzipper.read()
        dat = extracted_data

    # Write it to a file
    file.write(dat)
    file.close()
    # return file path
    return (path + " " + url)