462 lines
14 KiB
Python
462 lines
14 KiB
Python
# -*- coding: iso-8859-1 -*-
|
|
# Copyright (C) 2004-2005 Tristan Seligmann and Jonathan Jacobs
|
|
# Copyright (C) 2012-2013 Bastian Kleineidam
|
|
from __future__ import division, print_function
|
|
|
|
import urllib, urllib2, urlparse
|
|
import robotparser
|
|
import requests
|
|
import sys
|
|
import os
|
|
import cgi
|
|
import re
|
|
import traceback
|
|
import time
|
|
from htmlentitydefs import name2codepoint
|
|
|
|
from .decorators import memoized
|
|
from .output import out
|
|
from .configuration import UserAgent, AppName, App, SupportUrl
|
|
from .fileutil import has_module
|
|
|
|
has_curses = has_module("curses")
|
|
|
|
# Maximum content size for HTML pages
|
|
MaxContentBytes = 1024 * 1024 * 2 # 2 MB
|
|
|
|
# Maximum content size for images
|
|
MaxImageBytes = 1024 * 1024 * 20 # 20 MB
|
|
|
|
# Default number of retries
|
|
MaxRetries = 3
|
|
|
|
# Default connection timeout
|
|
ConnectionTimeoutSecs = 60
|
|
|
|
# The character set to encode non-ASCII characters in a URL. See also
|
|
# http://tools.ietf.org/html/rfc2396#section-2.1
|
|
# Note that the encoding is not really specified, but most browsers
|
|
# encode in UTF-8 when no encoding is specified by the HTTP headers,
|
|
# else they use the page encoding for followed link. See als
|
|
# http://code.google.com/p/browsersec/wiki/Part1#Unicode_in_URLs
|
|
UrlEncoding = "utf-8"
|
|
|
|
|
|
if hasattr(requests, 'adapters'):
|
|
# requests >= 1.0
|
|
requests.adapters.DEFAULT_RETRIES = MaxRetries
|
|
|
|
|
|
def tagre(tag, attribute, value, quote='"', before="", after=""):
|
|
"""Return a regular expression matching the given HTML tag, attribute
|
|
and value. It matches the tag and attribute names case insensitive,
|
|
and skips arbitrary whitespace and leading HTML attributes. The "<>" at
|
|
the start and end of the HTML tag is also matched.
|
|
@param tag: the tag name
|
|
@ptype tag: string
|
|
@param attribute: the attribute name
|
|
@ptype attribute: string
|
|
@param value: the attribute value
|
|
@ptype value: string
|
|
@param quote: the attribute quote (default ")
|
|
@ptype quote: string
|
|
@param after: match after attribute value but before end
|
|
@ptype after: string
|
|
|
|
@return: the generated regular expression suitable for re.compile()
|
|
@rtype: string
|
|
"""
|
|
if before:
|
|
prefix = r"[^>]*%s[^>]*\s+" % before
|
|
else:
|
|
prefix = r"(?:[^>]*\s+)?"
|
|
attrs = dict(
|
|
tag=case_insensitive_re(tag),
|
|
attribute=case_insensitive_re(attribute),
|
|
value=value,
|
|
quote=quote,
|
|
prefix=prefix,
|
|
after=after,
|
|
)
|
|
return r'<\s*%(tag)s\s+%(prefix)s%(attribute)s\s*=\s*%(quote)s%(value)s%(quote)s[^>]*%(after)s[^>]*>' % attrs
|
|
|
|
|
|
def case_insensitive_re(name):
|
|
"""Reformat the given name to a case insensitive regular expression string
|
|
without using re.IGNORECASE. This way selective strings can be made case
|
|
insensitive.
|
|
@param name: the name to make case insensitive
|
|
@ptype name: string
|
|
@return: the case insensitive regex
|
|
@rtype: string
|
|
"""
|
|
return "".join("[%s%s]" % (c.lower(), c.upper()) for c in name)
|
|
|
|
|
|
baseSearch = re.compile(tagre("base", "href", '([^"]*)'))
|
|
|
|
def getPageContent(url, max_content_bytes=MaxContentBytes, session=None):
|
|
"""Get text content of given URL."""
|
|
check_robotstxt(url)
|
|
# read page data
|
|
page = urlopen(url, max_content_bytes=max_content_bytes,
|
|
session=session)
|
|
data = page.text
|
|
# determine base URL
|
|
baseUrl = None
|
|
match = baseSearch.search(data)
|
|
if match:
|
|
baseUrl = match.group(1)
|
|
else:
|
|
baseUrl = url
|
|
return data, baseUrl
|
|
|
|
|
|
def getImageObject(url, referrer, max_content_bytes=MaxImageBytes):
|
|
"""Get response object for given image URL."""
|
|
return urlopen(url, referrer=referrer, max_content_bytes=max_content_bytes)
|
|
|
|
|
|
def fetchUrl(url, urlSearch, session=None):
|
|
"""Search for given URL pattern in a HTML page."""
|
|
data, baseUrl = getPageContent(url, session=session)
|
|
match = urlSearch.search(data)
|
|
if match:
|
|
searchUrl = match.group(1)
|
|
if not searchUrl:
|
|
raise ValueError("Match empty URL at %s with pattern %s" % (url, urlSearch.pattern))
|
|
out.debug('matched URL %r' % searchUrl)
|
|
return normaliseURL(urlparse.urljoin(baseUrl, searchUrl))
|
|
return None
|
|
|
|
|
|
def fetchUrls(url, imageSearch, prevSearch=None, session=None):
|
|
"""Search for given image and previous URL pattern in a HTML page."""
|
|
data, baseUrl = getPageContent(url, session=session)
|
|
# match images
|
|
imageUrls = set()
|
|
for match in imageSearch.finditer(data):
|
|
imageUrl = match.group(1)
|
|
if not imageUrl:
|
|
raise ValueError("Match empty image URL at %s with pattern %s" % (url, imageSearch.pattern))
|
|
out.debug('matched image URL %r with pattern %s' % (imageUrl, imageSearch.pattern))
|
|
imageUrls.add(normaliseURL(urlparse.urljoin(baseUrl, imageUrl)))
|
|
if not imageUrls:
|
|
out.warn("no images found at %s with pattern %s" % (url, imageSearch.pattern))
|
|
if prevSearch is not None:
|
|
# match previous URL
|
|
match = prevSearch.search(data)
|
|
if match:
|
|
prevUrl = match.group(1)
|
|
if not prevUrl:
|
|
raise ValueError("Match empty previous URL at %s with pattern %s" % (url, prevSearch.pattern))
|
|
prevUrl = normaliseURL(urlparse.urljoin(baseUrl, prevUrl))
|
|
else:
|
|
out.debug('no previous URL %s at %s' % (prevSearch.pattern, url))
|
|
prevUrl = None
|
|
return imageUrls, prevUrl
|
|
return imageUrls, None
|
|
|
|
|
|
def unescape(text):
|
|
"""Replace HTML entities and character references."""
|
|
def _fixup(m):
|
|
"""Replace HTML entities."""
|
|
text = m.group(0)
|
|
if text[:2] == "&#":
|
|
# character reference
|
|
try:
|
|
if text[:3] == "&#x":
|
|
text = unichr(int(text[3:-1], 16))
|
|
else:
|
|
text = unichr(int(text[2:-1]))
|
|
except ValueError:
|
|
pass
|
|
else:
|
|
# named entity
|
|
try:
|
|
text = unichr(name2codepoint[text[1:-1]])
|
|
except KeyError:
|
|
pass
|
|
return text
|
|
return re.sub(r"&#?\w+;", _fixup, text)
|
|
|
|
|
|
def normaliseURL(url):
|
|
"""Removes any leading empty segments to avoid breaking urllib2; also replaces
|
|
HTML entities and character references.
|
|
"""
|
|
if isinstance(url, unicode):
|
|
url = url.encode(UrlEncoding, 'ignore')
|
|
# XXX: brutal hack
|
|
url = unescape(url)
|
|
|
|
pu = list(urlparse.urlparse(url))
|
|
segments = pu[2].split('/')
|
|
while segments and segments[0] in ('', '..'):
|
|
del segments[0]
|
|
pu[2] = quote(unquote('/' + '/'.join(segments)))
|
|
# remove leading '&' from query
|
|
if pu[4].startswith('&'):
|
|
pu[4] = pu[4][1:]
|
|
# remove anchor
|
|
pu[5] = ""
|
|
return urlparse.urlunparse(pu)
|
|
|
|
|
|
def get_roboturl(url):
|
|
"""Get robots.txt URL from given URL."""
|
|
pu = urlparse.urlparse(url)
|
|
return urlparse.urlunparse((pu[0], pu[1], "/robots.txt", "", "", ""))
|
|
|
|
|
|
def check_robotstxt(url):
|
|
"""Check if robots.txt allows our user agent for the given URL.
|
|
@raises: IOError if URL is not allowed
|
|
"""
|
|
roboturl = get_roboturl(url)
|
|
rp = get_robotstxt_parser(roboturl)
|
|
if not rp.can_fetch(UserAgent, url):
|
|
raise IOError("%s is disallowed by robots.txt" % url)
|
|
|
|
|
|
@memoized
|
|
def get_robotstxt_parser(url):
|
|
"""Get a RobotFileParser for the given robots.txt URL."""
|
|
rp = robotparser.RobotFileParser()
|
|
req = urlopen(url, max_content_bytes=MaxContentBytes, raise_for_status=False)
|
|
if req.status_code in (401, 403):
|
|
rp.disallow_all = True
|
|
elif req.status_code >= 400:
|
|
rp.allow_all = True
|
|
elif req.status_code == 200:
|
|
rp.parse(req.content.splitlines())
|
|
return rp
|
|
|
|
|
|
def urlopen(url, referrer=None, max_content_bytes=None,
|
|
timeout=ConnectionTimeoutSecs, session=None, raise_for_status=True):
|
|
"""Open an URL and return the response object."""
|
|
out.debug('Open URL %s' % url)
|
|
headers = {'User-Agent': UserAgent}
|
|
if referrer:
|
|
headers['Referer'] = referrer
|
|
if session is None:
|
|
session = requests
|
|
kwargs = {
|
|
"headers": headers,
|
|
"timeout": timeout,
|
|
}
|
|
if not hasattr(requests, 'adapters'):
|
|
# requests << 1.0
|
|
kwargs["prefetch"] = False
|
|
kwargs["config"] = {"max_retries": MaxRetries}
|
|
try:
|
|
req = session.get(url, **kwargs)
|
|
check_content_size(url, req.headers, max_content_bytes)
|
|
if raise_for_status:
|
|
req.raise_for_status()
|
|
return req
|
|
except requests.exceptions.RequestException as err:
|
|
msg = 'URL retrieval of %s failed: %s' % (url, err)
|
|
raise IOError(msg)
|
|
|
|
|
|
def check_content_size(url, headers, max_content_bytes):
|
|
"""Check that content length in URL response headers do not exceed the
|
|
given maximum bytes.
|
|
"""
|
|
if not max_content_bytes:
|
|
return
|
|
if 'content-length' in headers:
|
|
size = int(headers['content-length'])
|
|
if size > max_content_bytes:
|
|
msg = 'URL content of %s with %d bytes exceeds %d bytes.' % (url, size, max_content_bytes)
|
|
raise IOError(msg)
|
|
|
|
|
|
def splitpath(path):
|
|
"""Split a path in its components."""
|
|
c = []
|
|
head, tail = os.path.split(path)
|
|
while tail:
|
|
c.insert(0, tail)
|
|
head, tail = os.path.split(head)
|
|
return c
|
|
|
|
|
|
def getRelativePath(basepath, path):
|
|
"""Get a path that is relative to the given base path."""
|
|
basepath = splitpath(os.path.abspath(basepath))
|
|
path = splitpath(os.path.abspath(path))
|
|
afterCommon = False
|
|
for c in basepath:
|
|
if afterCommon or path[0] != c:
|
|
path.insert(0, os.path.pardir)
|
|
afterCommon = True
|
|
else:
|
|
del path[0]
|
|
return os.path.join(*path)
|
|
|
|
|
|
def getQueryParams(url):
|
|
"""Get URL query parameters."""
|
|
query = urlparse.urlsplit(url)[3]
|
|
out.debug('Extracting query parameters from %r (%r)...' % (url, query))
|
|
return cgi.parse_qs(query)
|
|
|
|
|
|
def internal_error(out=sys.stderr, etype=None, evalue=None, tb=None):
|
|
"""Print internal error message (output defaults to stderr)."""
|
|
print(os.linesep, file=out)
|
|
print("""********** Oops, I did it again. *************
|
|
|
|
You have found an internal error in %(app)s. Please write a bug report
|
|
at %(url)s and include at least the information below:
|
|
|
|
Not disclosing some of the information below due to privacy reasons is ok.
|
|
I will try to help you nonetheless, but you have to give me something
|
|
I can work with ;) .
|
|
""" % dict(app=AppName, url=SupportUrl), file=out)
|
|
if etype is None:
|
|
etype = sys.exc_info()[0]
|
|
if evalue is None:
|
|
evalue = sys.exc_info()[1]
|
|
print(etype, evalue, file=out)
|
|
if tb is None:
|
|
tb = sys.exc_info()[2]
|
|
traceback.print_exception(etype, evalue, tb, None, out)
|
|
print_app_info(out=out)
|
|
print_proxy_info(out=out)
|
|
print_locale_info(out=out)
|
|
print(os.linesep,
|
|
"******** %s internal error, over and out ********" % AppName, file=out)
|
|
|
|
|
|
def print_env_info(key, out=sys.stderr):
|
|
"""If given environment key is defined, print it out."""
|
|
value = os.getenv(key)
|
|
if value is not None:
|
|
print(key, "=", repr(value), file=out)
|
|
|
|
|
|
def print_proxy_info(out=sys.stderr):
|
|
"""Print proxy info."""
|
|
print_env_info("http_proxy", out=out)
|
|
|
|
|
|
def print_locale_info(out=sys.stderr):
|
|
"""Print locale info."""
|
|
for key in ("LANGUAGE", "LC_ALL", "LC_CTYPE", "LANG"):
|
|
print_env_info(key, out=out)
|
|
|
|
|
|
def print_app_info(out=sys.stderr):
|
|
"""Print system and application info (output defaults to stderr)."""
|
|
print("System info:", file=out)
|
|
print(App, file=out)
|
|
print("Python %(version)s on %(platform)s" %
|
|
{"version": sys.version, "platform": sys.platform}, file=out)
|
|
stime = strtime(time.time())
|
|
print("Local time:", stime, file=out)
|
|
print("sys.argv", sys.argv, file=out)
|
|
|
|
|
|
def strtime(t):
|
|
"""Return ISO 8601 formatted time."""
|
|
return time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(t)) + \
|
|
strtimezone()
|
|
|
|
|
|
def strtimezone():
|
|
"""Return timezone info, %z on some platforms, but not supported on all.
|
|
"""
|
|
if time.daylight:
|
|
zone = time.altzone
|
|
else:
|
|
zone = time.timezone
|
|
return "%+04d" % (-zone//3600)
|
|
|
|
|
|
def rfc822date(indate):
|
|
"""Format date in rfc822 format."""
|
|
return time.strftime("%a, %d %b %Y %H:%M:%S GMT", time.gmtime(indate))
|
|
|
|
|
|
def asciify(name):
|
|
"""Remove non-ascii characters from string."""
|
|
return re.sub("[^0-9a-zA-Z_]", "", name)
|
|
|
|
|
|
def unquote(text):
|
|
"""Replace all percent-encoded entities in text."""
|
|
while '%' in text:
|
|
newtext = urllib.unquote(text)
|
|
if newtext == text:
|
|
break
|
|
text = newtext
|
|
return text
|
|
|
|
|
|
def quote(text, safechars='/'):
|
|
"""Percent-encode given text."""
|
|
return urllib.quote(text, safechars)
|
|
|
|
|
|
def strsize (b):
|
|
"""Return human representation of bytes b. A negative number of bytes
|
|
raises a value error."""
|
|
if b < 0:
|
|
raise ValueError("Invalid negative byte number")
|
|
if b < 1024:
|
|
return "%dB" % b
|
|
if b < 1024 * 10:
|
|
return "%dKB" % (b // 1024)
|
|
if b < 1024 * 1024:
|
|
return "%.2fKB" % (float(b) / 1024)
|
|
if b < 1024 * 1024 * 10:
|
|
return "%.2fMB" % (float(b) / (1024*1024))
|
|
if b < 1024 * 1024 * 1024:
|
|
return "%.1fMB" % (float(b) / (1024*1024))
|
|
if b < 1024 * 1024 * 1024 * 10:
|
|
return "%.2fGB" % (float(b) / (1024*1024*1024))
|
|
return "%.1fGB" % (float(b) / (1024*1024*1024))
|
|
|
|
|
|
def getDirname(name):
|
|
"""Replace slashes with path separator of name."""
|
|
return name.replace('/', os.sep)
|
|
|
|
|
|
def getFilename(name):
|
|
"""Get a filename from given name without dangerous or incompatible characters."""
|
|
# first replace all illegal chars
|
|
name = re.sub(r"[^0-9a-zA-Z_\-\.]", "_", name)
|
|
# then remove double dots and underscores
|
|
while ".." in name:
|
|
name = name.replace('..', '.')
|
|
while "__" in name:
|
|
name = name.replace('__', '_')
|
|
# remove a leading dot or minus
|
|
if name.startswith((".", "-")):
|
|
name = name[1:]
|
|
return name
|
|
|
|
|
|
def strlimit (s, length=72):
|
|
"""If the length of the string exceeds the given limit, it will be cut
|
|
off and three dots will be appended.
|
|
|
|
@param s: the string to limit
|
|
@type s: string
|
|
@param length: maximum length
|
|
@type length: non-negative integer
|
|
@return: limited string, at most length+3 characters long
|
|
"""
|
|
assert length >= 0, "length limit must be a non-negative integer"
|
|
if not s or len(s) <= length:
|
|
return s
|
|
if length == 0:
|
|
return ""
|
|
return "%s..." % s[:length]
|