class RobotCheck(Step):
cache = LRUCache(1000)
@classmethod
def post_save_clear(cls, sender, document, **kwargs):
logging.debug("Removing robots.txt cache information for: %s" % document.site)
for scheme in ('http', 'https'):
url = "%s://%s/robots.txt" % (scheme, document.site)
if url in cls.cache:
del cls.cache[url]
def __init__(self, settings, **kwargs):
"""Initialzation"""
self.settings = settings
self.fetch = Fetch(settings)
self.store = StoreResponse(settings)
@gen.engine
def process(self, task, callback=None, **kwargs):
url = "%s://%s/robots.txt" % (task.url_scheme, task.url_host)
if url in self.cache:
matcher = self.cache[url]
else:
matcher = self.cache[url] = yield gen.Task(self.build_matcher, url)
# TODO - Get Crawl Delay ``matcher.get_crawl_delay()``
if matcher.is_allowed_path(task.url_path):
callback((Step.CONTINUE, task))
else:
callback((Step.STOP, task))
@gen.engine
def build_matcher(self, url, callback):
task = Task(url)
extra_rules = []
for rule in RobotRule.objects(site=task.url_host):
extra_rules.append(('allow' if rule.flag else 'deny', rule.path, rule.order))
extra_rules = sorted(extra_rules, key=lambda x: x[2])
try:
parser = RobotParser(useragent=self.settings.USER_AGENT, extra_rules=extra_rules)
except Exception as e:
logging.error("Exception building robot parser", e)
raise e
v, t = yield gen.Task(self.fetch.process, task)
# Save the robots.txt
yield gen.Task(self.store.process, task)
if task.content:
parser.parse(task.content)
matcher = parser.matcher(self.settings.ROBOT_NAME)
callback(matcher)
def __init__(self, redis):
super(RedisQueue, self).__init__()
self.redis = redis
self._owned = {}
self._seen_cache = LRUCache(10000)
import socket, os
self.guid = "%s:%s" % (socket.gethostname(), os.getpid())
self._known_buckets = set()
class DNSHandler(object):
"""Cache DNS Names - this is plugged into the Tornado Async Client"""
def __init__(self):
self.cache = LRUCache(1000)
def get(self, host, default=None):
"""Mimic Dictionary get's but handling them through a cache"""
addr = self.cache.get(host, None)
if addr:
return addr
addrinfo = socket.getaddrinfo(host, 80, 0, 0, socket.SOL_TCP)
af, socktype, proto, canonname, sockaddr = addrinfo[0]
self.cache[host] = sockaddr[0]
return sockaddr[0]
class DNSHandler(object):
"""Cache DNS Names - this is plugged into the Tornado Async Client"""
def __init__(self):
self.cache = LRUCache(1000)
def get(self, host, default=None):
"""Mimic Dictionary get's but handling them through a cache"""
addr = self.cache.get(host, None)
if addr:
return addr
addrinfo = socket.getaddrinfo(host, 80, 0, 0, socket.SOL_TCP)
af, socktype, proto, canonname, sockaddr = addrinfo[0]
self.cache[host] = sockaddr[0]
return sockaddr[0]
def __init__(self):
self.cache = LRUCache(1000)
class Fetch(Step):
default_delay = 10
cache = LRUCache(1000)
def __init__(self, settings, user_settings=None, **kwargs):
self.client = httpclient.AsyncHTTPClient()
self.use_gzip = settings.USE_GZIP
self.user_agent = settings.USER_AGENT
self.ioloop = ioloop.IOLoop.instance()
if user_settings:
self.post_save(None, user_settings)
def process(self, task, callback=None, **kwargs):
task.request = httpclient.HTTPRequest(task.url, use_gzip=self.use_gzip, user_agent=self.user_agent)
tnow = time.time()
tv = self.cache.get(task.url_host, tnow)
if tv > tnow:
tnext = tv + self.delay
self.cache[task.url_host] = tnext
logging.debug("Fetching on timer in %.2f seconds" % (tnext - tnow))
self.ioloop.add_timeout(tnext, partial(self.fetch, task, callback))
else:
logging.debug("Fetcher not busy %r" % (tv))
self.cache[task.url_host] = tnow + self.delay
self.fetch(task, callback)
@property
def delay(self):
return self.__class__.default_delay
@gen.engine
def fetch(self, task, callback):
logging.debug("Starting fetch of url=%s" % (task.url))
task.response = yield gen.Task(self.client.fetch, task.request)
if task.response.body:
blen = len(task.response.body)
else:
blen = 0
try:
raw_len = int(task.response.headers.get('content-length', blen))
except:
raw_len = blen
logging.debug("Fetched code=%d len_raw=%d len=%d url=%s" % (task.response.code, raw_len, blen, task.url))
PageStats.crawled(task.response.code, raw_len)
if task.response.code == 200:
task.content = task.content_from_response()
elif task.response.code in (301, 302):
logging.error("Unhandled Redirect code=%d url=%s" % (task.response.code, task.url))
else:
task.content = None
callback((Step.CONTINUE, task))
@classmethod
def post_save(cls, sender, document, **kwargs):
cls.default_delay = document.crawl_delay
def __init__(self):
self.cache = LRUCache(1000)
