Remove third_party/twisted_8_1

third_party/twisted_8_1/twisted/names/root.py

-# -*- test-case-name: twisted.names.test.test_rootresolve -*-
-# Copyright (c) 2001-2004 Twisted Matrix Laboratories.
-# See LICENSE for details.
-
-
-"""
-Resolver implementation for querying successive authoritative servers to
-lookup a record, starting from the root nameservers.
-
-@author: U{Jp Calderone<mailto:exarkun@twistedmatrix.com>}
-
-todo::
-    robustify it
-    break discoverAuthority into several smaller functions
-    documentation
-"""
-
-from __future__ import generators
-
-import sys
-
-from twisted.python import log
-from twisted.internet import defer
-from twisted.names import dns
-from twisted.names import common
-
-def retry(t, p, *args):
-    assert t, "Timeout is required"
-    t = list(t)
-    def errback(failure):
-        failure.trap(defer.TimeoutError)
-        if not t:
-            return failure
-        return p.query(timeout=t.pop(0), *args
-            ).addErrback(errback
-            )
-    return p.query(timeout=t.pop(0), *args
-        ).addErrback(errback
-        )
-
-class _DummyController:
-    def messageReceived(self, *args):
-        pass
-
-class Resolver(common.ResolverBase):
-    def __init__(self, hints):
-        common.ResolverBase.__init__(self)
-        self.hints = hints
-
-    def _lookup(self, name, cls, type, timeout):
-        d = discoverAuthority(name, self.hints
-            ).addCallback(self.discoveredAuthority, name, cls, type, timeout
-            )
-        return d
-
-    def discoveredAuthority(self, auth, name, cls, type, timeout):
-        from twisted.names import client
-        q = dns.Query(name, type, cls)
-        r = client.Resolver(servers=[(auth, dns.PORT)])
-        d = r.queryUDP([q], timeout)
-        d.addCallback(r.filterAnswers)
-        return d
-
-def lookupNameservers(host, atServer, p=None):
-    # print 'Nameserver lookup for', host, 'at', atServer, 'with', p
-    if p is None:
-        p = dns.DNSDatagramProtocol(_DummyController())
-        p.noisy = False
-    return retry(
-        (1, 3, 11, 45),                     # Timeouts
-        p,                                  # Protocol instance
-        (atServer, dns.PORT),               # Server to query
-        [dns.Query(host, dns.NS, dns.IN)]   # Question to ask
-    )
-
-def lookupAddress(host, atServer, p=None):
-    # print 'Address lookup for', host, 'at', atServer, 'with', p
-    if p is None:
-        p = dns.DNSDatagramProtocol(_DummyController())
-        p.noisy = False
-    return retry(
-        (1, 3, 11, 45),                     # Timeouts
-        p,                                  # Protocol instance
-        (atServer, dns.PORT),               # Server to query
-        [dns.Query(host, dns.A, dns.IN)]    # Question to ask
-    )
-
-def extractAuthority(msg, cache):
-    records = msg.answers + msg.authority + msg.additional
-    nameservers = [r for r in records if r.type == dns.NS]
-
-    # print 'Records for', soFar, ':', records
-    # print 'NS for', soFar, ':', nameservers
-
-    if not nameservers:
-        return None, nameservers
-    if not records:
-        raise IOError("No records")
-    for r in records:
-        if r.type == dns.A:
-            cache[str(r.name)] = r.payload.dottedQuad()
-    for r in records:
-        if r.type == dns.NS:
-            if str(r.payload.name) in cache:
-                return cache[str(r.payload.name)], nameservers
-    for addr in records:
-        if addr.type == dns.A and addr.name == r.name:
-            return addr.payload.dottedQuad(), nameservers
-    return None, nameservers
-
-def discoverAuthority(host, roots, cache=None, p=None):
-    if cache is None:
-        cache = {}
-
-    rootAuths = list(roots)
-
-    parts = host.rstrip('.').split('.')
-    parts.reverse()
-
-    authority = rootAuths.pop()
-
-    soFar = ''
-    for part in parts:
-        soFar = part + '.' + soFar
-        # print '///////',  soFar, authority, p
-        msg = defer.waitForDeferred(lookupNameservers(soFar, authority, p))
-        yield msg
-        msg = msg.getResult()
-
-        newAuth, nameservers = extractAuthority(msg, cache)
-
-        if newAuth is not None:
-            # print "newAuth is not None"
-            authority = newAuth
-        else:
-            if nameservers:
-                r = str(nameservers[0].payload.name)
-                # print 'Recursively discovering authority for', r
-                authority = defer.waitForDeferred(discoverAuthority(r, roots, cache, p))
-                yield authority
-                authority = authority.getResult()
-                # print 'Discovered to be', authority, 'for', r
-##            else:
-##                # print 'Doing address lookup for', soFar, 'at', authority
-##                msg = defer.waitForDeferred(lookupAddress(soFar, authority, p))
-##                yield msg
-##                msg = msg.getResult()
-##                records = msg.answers + msg.authority + msg.additional
-##                addresses = [r for r in records if r.type == dns.A]
-##                if addresses:
-##                    authority = addresses[0].payload.dottedQuad()
-##                else:
-##                    raise IOError("Resolution error")
-    # print "Yielding authority", authority
-    yield authority
-
-discoverAuthority = defer.deferredGenerator(discoverAuthority)
-
-def makePlaceholder(deferred, name):
-    def placeholder(*args, **kw):
-        deferred.addCallback(lambda r: getattr(r, name)(*args, **kw))
-        return deferred
-    return placeholder
-
-class DeferredResolver:
-    def __init__(self, resolverDeferred):
-        self.waiting = []
-        resolverDeferred.addCallback(self.gotRealResolver)
-
-    def gotRealResolver(self, resolver):
-        w = self.waiting
-        self.__dict__ = resolver.__dict__
-        self.__class__ = resolver.__class__
-        for d in w:
-            d.callback(resolver)
-
-    def __getattr__(self, name):
-        if name.startswith('lookup') or name in ('getHostByName', 'query'):
-            self.waiting.append(defer.Deferred())
-            return makePlaceholder(self.waiting[-1], name)
-        raise AttributeError(name)
-
-def bootstrap(resolver):
-    """Lookup the root nameserver addresses using the given resolver
-
-    Return a Resolver which will eventually become a C{root.Resolver}
-    instance that has references to all the root servers that we were able
-    to look up.
-    """
-    domains = [chr(ord('a') + i) for i in range(13)]
-    # f = lambda r: (log.msg('Root server address: ' + str(r)), r)[1]
-    f = lambda r: r
-    L = [resolver.getHostByName('%s.root-servers.net' % d).addCallback(f) for d in domains]
-    d = defer.DeferredList(L)
-    d.addCallback(lambda r: Resolver([e[1] for e in r if e[0]]))
-    return DeferredResolver(d)
-
-if __name__ == '__main__':
-    if len(sys.argv) < 2:
-        print 'Specify a domain'
-    else:
-        log.startLogging(sys.stdout)
-        from twisted.names.client import ThreadedResolver
-        r = bootstrap(ThreadedResolver())
-        d = r.lookupAddress(sys.argv[1])
-        d.addCallbacks(log.msg, log.err).addBoth(lambda _: reactor.stop())
-        from twisted.internet import reactor
-        reactor.run()