"""
Scrapy Telnet Console extension
See documentation in docs/topics/telnetconsole.rst
"""
import pprint
import logging
import traceback
import binascii
import os
from twisted.internet import protocol
try:
from twisted.conch import manhole, telnet
from twisted.conch.insults import insults
TWISTED_CONCH_AVAILABLE = True
except (ImportError, SyntaxError):
_TWISTED_CONCH_TRACEBACK = traceback.format_exc()
TWISTED_CONCH_AVAILABLE = False
from scrapy.exceptions import NotConfigured
from scrapy import signals
from scrapy.utils.trackref import print_live_refs
from scrapy.utils.engine import print_engine_status
from scrapy.utils.reactor import listen_tcp
from scrapy.utils.decorators import defers
logger = logging.getLogger(__name__)
# signal to update telnet variables
# args: telnet_vars
update_telnet_vars = object()
[docs]class TelnetConsole(protocol.ServerFactory):
def __init__(self, crawler):
if not crawler.settings.getbool('TELNETCONSOLE_ENABLED'):
raise NotConfigured
if not TWISTED_CONCH_AVAILABLE:
raise NotConfigured(
'TELNETCONSOLE_ENABLED setting is True but required twisted '
'modules failed to import:\n' + _TWISTED_CONCH_TRACEBACK)
self.crawler = crawler
self.noisy = False
self.portrange = [int(x) for x in crawler.settings.getlist('TELNETCONSOLE_PORT')]
self.host = crawler.settings['TELNETCONSOLE_HOST']
self.username = crawler.settings['TELNETCONSOLE_USERNAME']
self.password = crawler.settings['TELNETCONSOLE_PASSWORD']
if not self.password:
self.password = binascii.hexlify(os.urandom(8)).decode('utf8')
logger.info('Telnet Password: %s', self.password)
self.crawler.signals.connect(self.start_listening, signals.engine_started)
self.crawler.signals.connect(self.stop_listening, signals.engine_stopped)
@classmethod
def from_crawler(cls, crawler):
return cls(crawler)
def start_listening(self):
self.port = listen_tcp(self.portrange, self.host, self)
h = self.port.getHost()
logger.info("Telnet console listening on %(host)s:%(port)d",
{'host': h.host, 'port': h.port},
extra={'crawler': self.crawler})
def stop_listening(self):
self.port.stopListening()
def protocol(self):
class Portal:
"""An implementation of IPortal"""
@defers
def login(self_, credentials, mind, *interfaces):
if not (
credentials.username == self.username.encode('utf8')
and credentials.checkPassword(self.password.encode('utf8'))
):
raise ValueError("Invalid credentials")
protocol = telnet.TelnetBootstrapProtocol(
insults.ServerProtocol,
manhole.Manhole,
self._get_telnet_vars()
)
return (interfaces[0], protocol, lambda: None)
return telnet.TelnetTransport(
telnet.AuthenticatingTelnetProtocol,
Portal()
)
def _get_telnet_vars(self):
# Note: if you add entries here also update topics/telnetconsole.rst
telnet_vars = {
'engine': self.crawler.engine,
'spider': self.crawler.engine.spider,
'slot': self.crawler.engine.slot,
'crawler': self.crawler,
'extensions': self.crawler.extensions,
'stats': self.crawler.stats,
'settings': self.crawler.settings,
'est': lambda: print_engine_status(self.crawler.engine),
'p': pprint.pprint,
'prefs': print_live_refs,
'help': "This is Scrapy telnet console. For more info see: "
"https://docs.scrapy.org/en/latest/topics/telnetconsole.html",
}
self.crawler.signals.send_catch_log(update_telnet_vars, telnet_vars=telnet_vars)
return telnet_vars