Source code for

# -*- coding: utf-8 -*-

    The CheckExternalLinksBuilder class.

    :copyright: Copyright 2007-2016 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.

import re
import socket
import codecs
import threading
from os import path

from six.moves import queue
from six.moves.urllib.request import build_opener, Request, HTTPRedirectHandler
from six.moves.urllib.parse import unquote
from six.moves.urllib.error import HTTPError
from six.moves.html_parser import HTMLParser
from docutils import nodes

# 2015-06-25  This exception was deprecated in Python 3.3 and
# removed in Python 3.5, however for backward compatibility reasons, we're not
# going to just remove it.  If it doesn't exist, define an exception that will
# never be caught but leaves the code in check_anchor() intact.
    from six.moves.html_parser import HTMLParseError
except ImportError:
    class HTMLParseError(Exception):

from import Builder
from sphinx.util import encode_uri
from sphinx.util.console import purple, red, darkgreen, darkgray, \
    darkred, turquoise
from sphinx.util.pycompat import TextIOWrapper

class RedirectHandler(HTTPRedirectHandler):
    """A RedirectHandler that records the redirect code we got."""

    def redirect_request(self, req, fp, code, msg, headers, newurl):
        new_req = HTTPRedirectHandler.redirect_request(self, req, fp, code,
                                                       msg, headers, newurl)
        req.redirect_code = code
        return new_req

# create an opener that will simulate a browser user-agent
opener = build_opener(RedirectHandler)
opener.addheaders = [('User-agent', 'Mozilla/5.0 (X11; Linux x86_64; rv:25.0) '
                      'Gecko/20100101 Firefox/25.0')]

class HeadRequest(Request):
    """Subclass of urllib2.Request that sends a HEAD request."""
    def __init__(self, *args, **kwargs):
        Request.__init__(self, *args, **kwargs)
        # we do not parse the response in HEAD, so accepting anything is okay
        self.headers['Accept-encoding'] = '*'

    def get_method(self):
        return 'HEAD'

class AnchorCheckParser(HTMLParser):
    """Specialized HTML parser that looks for a specific anchor."""

    def __init__(self, search_anchor):

        self.search_anchor = search_anchor
        self.found = False

    def handle_starttag(self, tag, attrs):
        for key, value in attrs:
            if key in ('id', 'name') and value == self.search_anchor:
                self.found = True

def check_anchor(f, anchor):
    """Reads HTML data from a filelike object 'f' searching for *anchor*.
    Returns True if anchor was found, False otherwise.
    parser = AnchorCheckParser(anchor)
        # Read file in chunks of 8192 bytes. If we find a matching anchor, we
        # break the loop early in hopes not to have to download the whole thing.
        chunk =
        while chunk and not parser.found:
            chunk =
    except HTMLParseError:
        # HTMLParser is usually pretty good with sloppy HTML, but it tends to
        # choke on EOF. But we're done then anyway.
    return parser.found

def get_content_charset(f):
    content_type = f.headers.get('content-type')
    if content_type:
        params = (p.strip() for p in content_type.split(';')[1:])
        for param in params:
            if param.startswith('charset='):
                return param[8:]

    return None

[docs]class CheckExternalLinksBuilder(Builder): """ Checks for broken external links. """ name = 'linkcheck' def init(self): self.to_ignore = [re.compile(x) for x in] self.good = set() self.broken = {} self.redirected = {} # set a timeout for non-responding servers socket.setdefaulttimeout(5.0) # create output file open(path.join(self.outdir, 'output.txt'), 'w').close() # create queues and worker threads self.wqueue = queue.Queue() self.rqueue = queue.Queue() self.workers = [] for i in range( thread = threading.Thread(target=self.check_thread) thread.setDaemon(True) thread.start() self.workers.append(thread) def check_thread(self): kwargs = {} if kwargs['timeout'] = def check_uri(): # split off anchor if '#' in uri: req_url, anchor = uri.split('#', 1) else: req_url = uri anchor = None # handle non-ASCII URIs try: req_url.encode('ascii') except UnicodeError: req_url = encode_uri(req_url) try: if anchor and and \ not anchor.startswith('!'): # Read the whole document and see if #anchor exists # (Anchors starting with ! are ignored since they are # commonly used for dynamic pages) req = Request(req_url) f =, **kwargs) encoding = 'utf-8' if hasattr(f.headers, 'get_content_charset'): encoding = f.headers.get_content_charset() or encoding else: encoding = get_content_charset(f) or encoding found = check_anchor(TextIOWrapper(f, encoding), unquote(anchor)) f.close() if not found: raise Exception("Anchor '%s' not found" % anchor) else: try: # try a HEAD request, which should be easier on # the server and the network req = HeadRequest(req_url) f =, **kwargs) f.close() except HTTPError as err: if err.code not in (403, 405): raise # retry with GET if that fails, some servers # don't like HEAD requests and reply with 403 or 405 req = Request(req_url) f =, **kwargs) f.close() except HTTPError as err: if err.code == 401: # We'll take "Unauthorized" as working. return 'working', ' - unauthorized', 0 else: return 'broken', str(err), 0 except Exception as err: return 'broken', str(err), 0 if f.url.rstrip('/') == req_url.rstrip('/'): return 'working', '', 0 else: new_url = f.url if anchor: new_url += '#' + anchor code = getattr(req, 'redirect_code', 0) return 'redirected', new_url, code def check(): # check for various conditions without bothering the network if len(uri) == 0 or uri.startswith(('#', 'mailto:', 'ftp:')): return 'unchecked', '', 0 elif not uri.startswith(('http:', 'https:')): return 'local', '', 0 elif uri in self.good: return 'working', 'old', 0 elif uri in self.broken: return 'broken', self.broken[uri], 0 elif uri in self.redirected: return 'redirected', self.redirected[uri][0], self.redirected[uri][1] for rex in self.to_ignore: if rex.match(uri): return 'ignored', '', 0 # need to actually check the URI for _ in range( status, info, code = check_uri() if status != "broken": break if status == "working": self.good.add(uri) elif status == "broken": self.broken[uri] = info elif status == "redirected": self.redirected[uri] = (info, code) return (status, info, code) while True: uri, docname, lineno = self.wqueue.get() if uri is None: break status, info, code = check() self.rqueue.put((uri, docname, lineno, status, info, code)) def process_result(self, result): uri, docname, lineno, status, info, code = result if status == 'unchecked': return if status == 'working' and info == 'old': return if lineno:'(line %4d) ' % lineno, nonl=1) if status == 'ignored':'-ignored- ') + uri) elif status == 'local':'-local- ') + uri) self.write_entry('local', docname, lineno, uri) elif status == 'working':'ok ') + uri + info) elif status == 'broken': self.write_entry('broken', docname, lineno, uri + ': ' + info) if or self.warn('broken link: %s' % uri, '%s:%s' % (self.env.doc2path(docname), lineno)) else:'broken ') + uri + red(' - ' + info)) elif status == 'redirected': text, color = { 301: ('permanently', darkred), 302: ('with Found', purple), 303: ('with See Other', purple), 307: ('temporarily', turquoise), 0: ('with unknown code', purple), }[code] self.write_entry('redirected ' + text, docname, lineno, uri + ' to ' + info)'redirect ') + uri + color(' - ' + text + ' to ' + info)) def get_target_uri(self, docname, typ=None): return '' def get_outdated_docs(self): return self.env.found_docs def prepare_writing(self, docnames): return def write_doc(self, docname, doctree): n = 0 for node in doctree.traverse(nodes.reference): if 'refuri' not in node: continue uri = node['refuri'] lineno = None while lineno is None: node = node.parent if node is None: break lineno = node.line self.wqueue.put((uri, docname, lineno), False) n += 1 done = 0 while done < n: self.process_result(self.rqueue.get()) done += 1 if self.broken: = 1 def write_entry(self, what, docname, line, uri): output =, 'output.txt'), 'a', 'utf-8') output.write("%s:%s: [%s] %s\n" % (self.env.doc2path(docname, None), line, what, uri)) output.close() def finish(self): for worker in self.workers: self.wqueue.put((None, None, None), False)