def robotExclusion(link):
# print("Robot exclusion.....")
rp=RobotFileParser();
rp.set_url(urljoin(link, '/robot.txt'))
rp.read()
# print(rp.can_fetch("*", link))
return rp.can_fetch("*", link)
def _init_robots(self, root_url):
url = urlparse(root_url)
robots_url = url.scheme + '://' + url.netloc + '/robots.txt'
parser = RobotFileParser(robots_url)
parser.read()
return parser
def http_open(self, request):
url = request.get_full_url()
host = urlsplit(url)[1]
robots_url = urlunsplit(('http', host, '/robots.txt', '', ''))
rp = RobotFileParser(robots_url)
rp.read()
if not rp.can_fetch(self.agentname, url):
raise RuntimeError('Forbidden by robots.txt')
return urllib2.HTTPHandler.http_open(self, request)
def check_robots_txt(self, parsed_link):
"""
Checks the site's robots.txt file to make sure our user agent is allowed to visit that url.
:param parsed_link:
:return: boolean . True if we're allowed to visit (or there's no robots.txt)
"""
rp = RobotFileParser()
rp.set_url(urljoin(parsed_link.geturl(), '/robots.txt'))
rp.read()
return rp.can_fetch(self.user_agent, parsed_link.geturl())
def test_robots_txt(self):
parser = RobotFileParser(self.live_server_url + '/robots.txt')
parser.read()
url = self.live_server_url + '/index.html'
for robot in self.robots:
self.assertTrue(parser.can_fetch(robot, url))
url = self.live_server_url + '/admin/'
for robot in self.robots:
self.assertFalse(parser.can_fetch(robot, url))
def robots_get(url, *args, **kwargs):
u = urlparse(url)
robot_url = '{scm}://{loc}/robots.txt'.format(scm=u.scheme, loc=u.netloc)
robot = RobotFileParser(robot_url)
robot.read()
ua = kwargs.get('headers', dict()).get('User-Agent', '*')
if not robot.can_fetch(ua, url):
return 'Not Allowed By robots.txt'
delay = robot.crawl_delay(ua)
if delay:
time.sleep(delay)
return requests.get(url, *args, **kwargs)
def check_robots(base_url, ext_url):
'''
Check the robots.txt
Prints note if base_url + ext_url is legal for crawling
'''
bot = RobotFileParser(base_url + '/robots.txt')
bot.read()
if bot.can_fetch('*', base_url + ext_url):
print('robots.txt permits parsing')
else:
print('Do not parse')
return bot
def __getParser(self, url):
if url == '':
return False
site = 'https://' + url + '/robots.txt'
# print("robotparse: " + site)
try:
rp = RobotFileParser(site)
rp.read()
except Exception as e:
return False
else:
return rp
def is_scraping_allowed(self):
"""
Megnezi, hogy a robots.txt nem tiltja-e a scrapelest. Nem igazan teljes
az ellenorzes, mert csak az all job url-t vizsgalja.
:return:
"""
robot_parser = RobotFileParser()
robots_url = urljoin(self.base_url, 'robots.txt')
robot_parser.set_url(robots_url)
robot_parser.read()
return robot_parser.can_fetch('*', urljoin(
self.base_url, self.all_job_url))
def retrieve_site_robots(self):
url = url_normalize(self.domain + "/robots.txt")
rp = RobotFileParser()
rp.set_url(url)
try:
rp.read()
self.robots_content = str(rp)
if rp.site_maps():
self.retrieve_sitemap_content(rp)
except Exception as e:
self.robots_content = ""
print(f"ERROR retrieving robots.txt for {self.domain}")
print(e)
class Exclusion(object):
def __init__(self):
self.robot_cache = {}
self.rp = RobotFileParser()
# Broken? disallows anything in the robots.txt.
# Even if it is marked with Allow:
def test_url(self, url):
self.rp = RobotFileParser()
robot_url = uu.domain_name(url) + '/robots.txt'
self.rp.set_url(robot_url)
self.rp.read()
return self.rp.can_fetch('*', url)
def get_robots(seed_url):
"""
获取机器人守则
:param seed_url:
:return: 返回一个 urllib.robotparser.RobotFileParser 对象 或者 None
"""
rp = RobotFileParser()
rp.set_url(urljoin(seed_url, '/robots.txt'))
try:
rp.read()
except Exception as e:
return None
return rp
def GetRobotsTxt(url):
rp = RobotFileParser()
rp.set_url(url)
rp.read()
print(
rp.can_fetch(
'*',
'https://book.douban.com/tag/?view=type&icn=index-sorttags-all'))
print(rp.can_fetch('*', 'https://book.douban.com/tag/%E5%B0%8F%E8%AF%B4'))
print(
rp.can_fetch(
'*',
'https://book.douban.com/tag/%E6%9D%91%E4%B8%8A%E6%98%A5%E6%A0%91?start=40&type=S'
))
def can_fetch(self, url):
parse = urllib.parse.urlparse(url)
hostname = parse.hostname
try:
robot = self.robot[hostname]
except Exception:
roboturl = urllib.parse.urlunparse((parse.scheme,parse.netloc,"robots.txt","","",""))
robot = RobotFileParser(roboturl)
try:
robot.read()
except Exception:
robot = _RobotAllowAll()
self.__robots[hostname] = robot
return robot.can_fetch("*", url)
def can_fetch_url(robots_url, site_url, useragent="*"):
"""
Using robots.txt found at robots_url, decides if useragent can fetch
site url
:param robots_url: robots.txt url
:param site_url: to be fetched url
:param useragent: useragent
:return: True, if fetching is allowed
"""
rfp = RobotFileParser()
rfp.set_url(robots_url)
rfp.read()
return rfp.can_fetch(useragent=useragent, url=site_url)
def create_sdomain_robot(url: str):
url = urlparse(url)
robot = RobotFileParser()
robot.set_url(url.scheme + '://' + url.netloc + "/robots.txt")
def can_crawl(url_with_path: str):
return robot.can_fetch('*', url_with_path)
#may not be able to read a file, if so we will just not have a robot for that
#subdomain. Assumes all pages can be crawled
try:
robot.read()
robots[url.netloc] = can_crawl
except:
pass
class RobotsTxt:
def __init__(self, base_url):
try:
url = urljoin(base_url, 'robots.txt')
self.rp = RobotFileParser()
self.set_url(url)
self.rp.read()
except:
self.rp = None
def canFetch(self, url):
if self.rp is None:
return True
else:
return self.rp.can_fetch('*', url)
def can_fetch(self, url):
"""Check if it is allowed to scrape the resource hosted at url
This is done by parsing the robots.txt of the host.
"""
parsed_url = urlparse(url)
# Fetching and parsing the robots.txt file can be expensive in it-self.
# Let's cache the RobotFileParser instances, one per host, on the
# scraper itself to reuse them for consecutive queries.
rfp = self.robot_file_parsers.get(parsed_url.hostname)
if rfp is None:
rfp = RobotFileParser(self.get_robot_url(url))
rfp.read()
self.robot_file_parsers[parsed_url.hostname] = rfp
return rfp.can_fetch(self.user_agent, parsed_url.path)
def robotsTxtParseSeeds():
# Stores the robot.txt of the seed urls in DataStore.RobotChecks
seedUrls = ['https://today.uci.edu/department/information_computer_sciences/',
'https://www.ics.uci.edu',
'https://www.cs.uci.edu',
'https://www.informatics.uci.edu',
'https://www.stat.uci.edu']
for seedUrl in seedUrls:
scheme = urlparse(seedUrl).scheme
domain = getSubDomain(seedUrl)
robotTxtUrl = f"{scheme}://{domain}/robots.txt"
robot = RobotFileParser()
robot.set_url(robotTxtUrl)
robot.read()
DataStore.robotsCheck[domain] = robot
class RobotsTxt:
def __init__(self) -> None:
self.state = None # type: Any
def allowed(self, url: URL) -> bool:
# We don't have info about this domain for now, so we going to request
# robots.txt
if self.state is None:
self.request(url.link("/robots.txt"))
# We actually can't find out is there robots.txt or not
# so we going to allow all in this case.
if self.state is False or self.state.allow_all:
return True
if not self.state.last_checked and self.state.disallow_all:
return False
# find entry
return allowed(matched_rules(self._entry(), url))
def request(self, url: str) -> None:
""" Perform robots.txt request """
if self.state is not None:
return
try:
self.state = RobotFileParser()
self.state.set_url(url)
self.state.read()
except Exception:
self.state = False
# This is mostly transferred logics from robotparser.py,
# but we trying to follow 2019 extension of the Google's Robots Txt
# protocol and allow, disallowed pathes.
# https://www.contentkingapp.com/blog/implications-of-new-robots-txt-rfc/
# https://tools.ietf.org/html/draft-koster-rep-04
def _entry(self) -> Any:
for entry in self.state.entries:
if entry.applies_to(user_agent):
return entry
return self.state.default_entry
def init_robots(allowed_domains):
robot_filters = {}
for domain in allowed_domains:
rp = RobotFileParser()
url = "https://{}/robots.txt".format(domain)
rp.set_url(url)
rp.read()
robot_filters[domain] = rp
def crawl_prohibited(robots, url):
domain = urlparse(url).netloc
if domain not in robots:
return True
return not robots[domain].can_fetch('*', url)
return lambda url: crawl_prohibited(robot_filters, url)
def get_robots_text(self,url):
"""get_robots_txt
url: robots.txt を確認するサイトURL
"""
try:
rp = RobotFileParser()
# robots の url 取得
parsed_url = urlparse(url)
robots_url = "{0.scheme}://{0.netloc}/robots.txt".format(parsed_url)
# robots.txt 取得
rp.set_url(robots_url)
rp.read()
# 取得していいか確認
return rp.can_fetch("*",url)
except:
return False
def _gather_robots_files(self) -> Dict[str, RobotFileParser]:
robot_cache = dict()
if isinstance(self._net_locations, list):
net_locations = self._net_locations
else:
net_locations = [self._net_locations]
for host in net_locations:
try:
parser = RobotFileParser(
url='http://{}/robots.txt'.format(host))
parser.read()
robot_cache[host] = parser
except Exception:
logger = logging.getLogger('ScrapIO')
logger.warning(
'Was unable to successfully download robots.txt, for: {}'.
format(host))
return robot_cache
def get_robots_txt(cls, url):
""" get_robots_txt
url: robots.txt を確認するサイトURL
"""
try:
# robots.txt 用パーサー
rp = RobotFileParser()
# robots の url 取得
parsed_url = urlparse(url)
robots_url = "{0.scheme}://{0.netloc}/robots.txt".format(
parsed_url)
# robots.txt 取得
rp.set_url(robots_url)
rp.read()
# 取得していいか確認
return rp.can_fetch("*", url)
except Exception as e:
raise Exception(e.args[0])
def can_read(url):
domain = domain_name(url)
if domain not in Permissions:
rp = RobotFileParser()
rp.set_url(urljoin('http://' + domain, 'robots.txt'))
try:
rp.read()
except:
return False
Permissions[domain] = rp
res = False
try:
res = Permissions[domain].can_fetch("*", url)
except:
return False
return res
def read_all_sitemaps(get_accredited: bool, get_page=0):
"""
get all the companies using the sitemaps. get_page is used for batch processes.
set it to -1 to get everything. returns a list of the companies in BBB
"""
robot_parser = RobotFileParser()
robot_parser.set_url(urljoin(ICFG.STARTING_URL, 'robots.txt'))
robot_parser.read()
site_maps = robot_parser.site_maps()
sitemap_list = [
i for i in site_maps
if i.find("sitemap") + 1 and i.find('business-profiles-index') + 1
]
if not get_accredited:
[sitemap_list.pop(i.find("accredited")) for i in sitemap_list]
sitemap = sitemap_list[0]
else:
sitemap = [
sitemap_list.pop(i.find("accredited")) for i in sitemap_list
][0]
sitemap_pages = requests.get(sitemap, headers=r.choice(ICFG.HEADERS))
soup = bs(sitemap_pages.content, "lxml-xml")
pages_with_business_profiles = [i.get_text() for i in soup.find_all('loc')]
business_profile_list = []
if get_page == -1:
for page in pages_with_business_profiles:
business_pages = requests.get(page, headers=r.choice(ICFG.HEADERS))
soup = bs(business_pages.content, "lxml-xml")
business_profile_list.extend(
[i.get_text() for i in soup.find_all('loc')])
else:
page = pages_with_business_profiles[get_page]
business_pages = requests.get(page, headers=r.choice(ICFG.HEADERS))
soup = bs(business_pages.content, "lxml-xml")
business_profile_list.extend(
[i.get_text() for i in soup.find_all('loc')])
return business_profile_list
def get_parsed_robots(self, base_url):
rp = RobotFileParser()
robots_url = base_url + '/robots.txt'
try:
is_valid = self.check_and_save_robots(robots_url)
if (not is_valid):
raise Exception("Not found robots")
if (base_url in self.parsed_robots_domains.keys()):
rp = self.parsed_robots_domains[base_url]
else:
rp.set_url(robots_url)
rp.read()
self.parsed_robots_domains[base_url] = rp
except:
# allow all
rp.set_url('https://ku.ac.th')
rp.read()
finally:
return rp
def can_read(url):
domain = domain_name(url)
if domain not in Permissions:
rp = RobotFileParser()
rp.set_url(urljoin("http://" + domain, "robots.txt"))
try:
rp.read()
except:
return False
Permissions[domain] = rp
res = False
try:
res = Permissions[domain].can_fetch("*", url)
except:
return False
return res
def parse(self, response):
le = LinkExtractor(unique=True)
# Use robot file parser to check if links extracted are allowed
rp = RobotFileParser()
BASE_URL = response.request.url
DOMAIN = extract(BASE_URL).domain
rp.set_url(BASE_URL + '/robots.txt')
rp.read()
# Extract all the links
all_links = le.extract_links(response)
for link in all_links:
# Ensure same domain
if extract(link.url).domain == DOMAIN:
if rp.can_fetch("*", link.url):
# Enforcing unique urls
if link.url not in self.unique_urls:
self.write_to_file(link.url, DOMAIN)
self.unique_urls.add(link.url)
yield Request(link.url, callback=self.parse)
def parse_robotstxt(url):
"""
Parse robots.txt
"""
parsed = urlsplit(url)
if parsed.scheme not in ['http', 'https']:
return False
if parsed.netloc == '':
return False
robot = RobotFileParser()
robot.set_url(parsed.scheme + "://" + parsed.netloc + "/robots.txt")
robot.read()
return dict(
allowed=robot.can_fetch('*', url),
rate=robot.request_rate('*'),
delay=robot.crawl_delay('*'),
)
def check_delay(user_agent, url):
robots_url = to_robots(url)
# Fetch the delay for all programs, ond this one in particular.
general_delay, have_general = get_delay(GENERAL_AGENT, robots_url)
agent_delay, have_agent = get_delay(user_agent, robots_url)
# The next part is straightforward:
# Check the general rules, and then check the program's rules,
# if there are rules.
robots_parser = RobotFileParser(robots_url)
robots_parser.read()
if (have_general and not robots_parser.can_fetch("*", url)):
return None
if (have_agent and not robots_parser.can_fetch(user_agent, url)):
return None
# Use the larger delay.
if general_delay < agent_delay:
return agent_delay
else:
return general_delay
def can_fetch(self, url):
parsed = urlparse(url)
if parsed.netloc in self.robots_txt_dict:
if self.robots_txt_dict[
parsed.
netloc] == 0: # 0 means that a robots.txt was not able to be gotten from that site so it assumes its all able to be crawled
return True
return self.robots_txt_dict[parsed.netloc].can_fetch('*', url)
try:
rp = RobotFileParser()
rp.set_url('{}://{}/robots.txt'.format(parsed.scheme,
parsed.netloc))
rp.read()
self.robots_txt_dict[parsed.netloc] = rp
return rp.can_fetch('*', url)
except:
print('error getting robots.txt')
self.robots_txt_dict[parsed.netloc] = 0
return True
def get_number_of_pages_of_all_sitemaps(get_accredited: bool):
robot_parser = RobotFileParser()
robot_parser.set_url(urljoin(ICFG.STARTING_URL, 'robots.txt'))
robot_parser.read()
site_maps = robot_parser.site_maps()
sitemap_list = [
i for i in site_maps
if i.find("sitemap") + 1 and i.find('business-profiles-index') + 1
]
if not get_accredited:
[sitemap_list.pop(i.find("accredited")) for i in sitemap_list]
sitemap = sitemap_list[0]
else:
sitemap = [
sitemap_list.pop(i.find("accredited")) for i in sitemap_list
][0]
sitemap_pages = requests.get(sitemap, headers=r.choice(ICFG.HEADERS))
soup = bs(sitemap_pages.content, "lxml-xml")
pages_with_business_profiles = [i.get_text() for i in soup.find_all('loc')]
return len(pages_with_business_profiles)
def scrape_urls(URL, destfile):
''' This function will scrape all of the URLs
from a given site and store them in a file.
This function accepts two arguments, the
target URL and a file name of your choosing
to store the links in, both as strings.'''
links = []
#open the robots.txt file, which contains scraping permissions
robotparser = RobotFileParser()
robotparser.set_url(parse.urljoin(URL_base, 'robots.txt'))
robotparser.read()
#determine whether you're allowed to scraoe
if robotparser.can_fetch(useragent='Python-urllib/3.6', url=URL):
#open the page as a file object and save its contents
with request.urlopen(URL) as response:
content = response.read()
#make a beautifulSoup object from the content, to be read as HTML
soup = BeautifulSoup(content, 'html.parser')
#'a' is a link in HTML
for a in soup.find_all('a'):
#below is necessary to make sure your link has
#a web address associated with it
if a.has_attr('href'):
links.append(a['href'])
#only proceed if the "links" list was populated in previous step
if links:
#save all of the link URLS in an external file
with open(destfile, 'w') as outfile:
for link in links:
#newline character makes the links separate!
outfile.write(link + '\n')
def crawl_if_eligible(self, url):
notAllowedException = Exception(
f"Page not allowed to be crawled by this User-Agent: {self.user_agent}"
)
rp = RobotFileParser()
rp.set_url(f"{url}/robots.txt")
rp.read()
eligible = rp.can_fetch(self.user_agent, url)
if not eligible:
raise notAllowedException
if eligible:
res = self.visit(url, method="GET")
sitemap_data = defaultdict(dict)
sitemaps = rp.site_maps()
for url in sitemaps:
sitemap_res = self.visit(url, method="GET")
hash_hex = md5(url.encode("utf-8")).hexdigest()[:8]
sitemap_data[hash_hex]["url"] = url
content = xmltodict.parse(sitemap_res.text)
sitemap_data[hash_hex]["content"] = content
return {
"res": res,
"sitemap_res": sitemap_data,
}
def check_robots(robots_path):
"""
robots.txtをチェックし、アクセス間隔を取得
Parameters
----------
robots_path : String
robots.txtのURL
Returns
-------
int
記事取得間隔(秒)
"""
# パス未指定なら適当な間隔を返却
if robots_path == None or "":
return random.randint(5, 10)
rp = RobotFileParser()
rp.set_url(robots_path)
rp.read()
delay = None
try:
delay = rp.crawl_delay('*')
if delay == None:
raise AttributeError
except AttributeError:
delay = random.randint(5, 10)
return delay
def parse_robots(base_url):
rp = RobotFileParser()
rp.set_url(base_url + '/robots.txt')
rp.read()
return rp
class SiteMap():
""" This class composes of all the functionalities needed to generate site_map"""
def __init__(self, main_page=None, robotrules=True, threadcount=1):
"""ctor that checks args and decides to enable single or multithreaded
generation of sitemap
"""
logging.info("Consider Robot.txt ? ==> "+str(robotrules))
self.robotrules = robotrules
self.site_map = {}
self.unvisited = set([])
self.start_page = None
self.robot_txt_rules = None
if main_page:
self.unvisited.add(main_page)
try:
self.start_page = urlparse(main_page).netloc
except:
logging.error("Improper URL, Please provide a Valid Url:"+main_page)
exit(0)
if self.robotrules == "True":
try:
logging.info("robot.txt respected")
self.robot_txt_rules = RobotFileParser()
self.robot_txt_rules.set_url(main_page + "/robots.txt")
self.robot_txt_rules.read()
except:
logging.error("Unable to read the robot.txt file")
self.robotrules = False # error reading robot.txt, ignore it forever
self.threadcount = int(threadcount)
def execute(self):
if self.threadcount <= 1: # if single threaded model is chosen, avoid threading
self.generate()
else:
self.start() # fasten by multi threads
def start(self):
"""This creates a pool of chosen limit so as to have the control and
spawns the main function and waits until process and subsequently
spawned process finish.
"""
self.pool = pool.Pool(self.threadcount)
self.pool.spawn(self.generate_parallels)
self.pool.join()
self.generate_reports()
def generate(self):
"""Non multithreaded model method that crawls until all pages are
crawled and assets are extracted. Once its done, it creates the
sitemap and assets json file for the given domain.
"""
while self.unvisited:
self.crawl()
self.generate_reports()
def generate_reports(self):
"""composes the xml tags with the keys in site_map member which are
nothing but the sitemap urls
"""
header = """<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
xmlns:xhtml="http://www.w3.org/1999/xhtml"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9
http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
"""
footer = """\n</urlset>\n"""
entry = "\t<url><loc>%s</loc></url>\n"
xml = header
for url in self.site_map.keys():
xml += entry % (url)
xml += footer
name = self.start_page.replace(".", "_")
self.create_file("%s.xml" % (name), xml)
self.create_file("%s_assets.json" % (name), json.dumps(self.site_map, indent=2, sort_keys=True))
def generate_parallels(self):
"""
This method is similar to recursive in a way that crawls pages and clears
the queue, which is self.unvisited. It stops when there are no urls to crawl
and all threads in pool are empty i.e they are not active anymore due to
finishing of crawling. Since its spawning a new thread and not calling
directly, it is a nice way to go about it for now :)
[Note:] There is a limit for recursion in Python and it can be increased by
sys.setrecursionlimit(1500)
An assumption has been made for this implementation that a website that has
more than 500 nested links needs a bit higher design in terms to store the
assets which might go above a hundred MB. In such cases, this can just be
converted into a loop. More over, there is no extra stack variables.
"""
self.crawl()
while len(self.unvisited) > 0 and not self.pool.full():
self.pool.spawn(self.generate_parallels)
def create_file(self, file, content):
"""writes the given content to the file"""
f = open(file, 'w')
f.write(content)
f.close()
def compose_url_from_href(self, page, href):
"""composes a proper url from domainlink and intralinks with in the page"""
url = urlparse(page)
if href.startswith('/'):
return "http://%s%s"%(url.netloc, href)
elif href.startswith('#'):
return "http://%s%s%s"%(url.netloc, url.path, href)
elif href.startswith('./'):
return "http://%s%s"%(url.netloc, href[1:])
elif not href.startswith('http'):
return "http://" + url.netloc + '/' + href
elif href.endswith('/'):
return href[:-1]
return href
def get_out_going_links(self, page, html_body):
"""extracts all the outgoing links and adds links that belong to
main page domain for further crawling if they are not crawled yet
This avoids:
- links that are .zip files
- links mentioned in href that are javascript methods
- mailto: links
"""
soup = BeautifulSoup(html_body, "html.parser")
valid_links_for_this_page = []
for a in soup.find_all('a', href=True):
href = a['href'].lower()
href = self.compose_url_from_href(page, href)
# clean the href so that it will have legitimate urls instead of #cluttered ones and q=param prints
href = urldefrag(href)[0] # skip intra links [this took time to find out !] ##1
# remove query params as only the path matters
if href.find('?') != -1:
href = href[:href.find('?')] ##2
new_page = urlparse(href)
# add to the queue only it it doesn't cause a cycle
# assumption: if a link ends with domain.com, assuming it can be crawled to make sitemap complete
if not str(new_page.netloc).endswith(self.start_page): # doesn't belong to domain
valid_links_for_this_page.append(href)
continue
if self.robot_allows(href) and \
not href in self.site_map and \
not href in self.unvisited and \
not 'javascript:' in href and \
not 'mailto:' in href:
if not ( href.endswith(".zip") or
href.endswith(".gz") or
href.endswith(".gzip") or
href.endswith(".tar") or
href.endswith(".bz2") or
href.endswith(".jpg") or
href.endswith(".png") or
href.endswith(".exe")
):
self.unvisited.add(href)
valid_links_for_this_page.append(href)
return valid_links_for_this_page
def get_assets(self, page, headers, html_body):
"""A nice feature of response header is that it reports the last-modified
time of the link on the server. If we are doing regular crawling, we can
avoid if the link is not updates since the last time. This method is
useful for indexing the data so as to minimize the crawling effort to
save execution time.
It updates the site_map dictionary with the links, css, images and scripts
"""
if 'last-modified' in headers:
date = headers['Last-Modified']
else:
date = headers['Date']
soup = BeautifulSoup(html_body, "html.parser")
img = soup.findAll("img")
css = soup.findAll("link", {"rel": "stylesheet"})
js = soup.findAll('script')
self.site_map[page] = {
'date': date,
'links': self.get_out_going_links(page, html_body),
'css': [c['href'] for c in css],
'img': [i['src'] for i in img],
'js': [x.get('src', 'inline jscode') for x in js]
}
def crawl(self):
"""This actually opens the url and calls the assets method """
if len(self.unvisited) <= 0:
return
page = self.unvisited.pop()
if page in self.site_map:
return
logging.info("Starting to Crawl Page: " + page)
try:
response = self.access_page(page)
if (response.status_code != 200):
return None
html_body = response.text
self.get_assets(page, response.headers, html_body)
except:
logging.error("Issue while opening url: %s" + page)
return None
logging.debug("Crawled Pages: {}".format(len(self.site_map)))
def access_page(self, url):
"""accesses the url from the server. This method was created
to enable mock tests.
"""
return requests.get(url)
def get_site_map(self):
"""exposes site_map"""
return self.site_map
def set_start_page(self, url):
"""sets the start page for the crawler"""
self.start_page = url
def robot_allows(self, link):
"""method to check if link can be accessed as per robot rules"""
if not self.robotrules: return True
try:
if self.robot_txt_rules.can_fetch("*", link):
return True
return False
except:
return True
# Copyright(C) 2018 刘珅珅
# Environment: python 3.6.4
# Date: 2018.9.8
# robots协议测试
from urllib.robotparser import RobotFileParser
url = 'http://www.jianshu.com/robots.txt'
rp = RobotFileParser(url)
rp.read()
# 在scrapy中，如果希望爬取robots.txt禁止的页面，需要禁用robots
print(rp.can_fetch('*', 'http://www.jianshu.com/p/b67554025d7d')) # False，不允许爬取
class Crawler():
# Variables
parserobots = False
output = None
report = False
config = None
domain = ""
exclude = []
skipext = []
drop = []
debug = False
tocrawl = set([])
crawled = set([])
excluded = set([])
marked = {}
# TODO also search for window.location={.*?}
linkregex = re.compile(b'<a href=[\'|"](.*?)[\'"].*?>')
rp = None
response_code = {}
nb_url = 1 # Number of url.
nb_rp = 0 # Number of url blocked by the robots.txt
nb_exclude = 0 # Number of url excluded by extension or word
output_file = None
target_domain = ""
def __init__(self,
parserobots=False,
output=None,
report=False,
domain="",
exclude=[],
skipext=[],
drop=[],
debug=False):
self.parserobots = parserobots
self.output = output
self.report = report
self.domain = domain
self.exclude = exclude
self.skipext = skipext
self.drop = drop
self.debug = debug
if self.debug:
logging.basicConfig(level=logging.DEBUG)
self.tocrawl = set([domain])
try:
self.target_domain = urlparse(domain)[1]
except:
raise ("Invalid domain")
if self.output:
try:
self.output_file = open(self.output, 'w')
except:
logging.debug("Output file not available.")
exit(255)
def run(self):
print(config.xml_header, file=self.output_file)
logging.debug("Start the crawling process")
while len(self.tocrawl) != 0:
self.__crawling()
logging.debug("Crawling as reach the end of all found link")
print(config.xml_footer, file=self.output_file)
def __crawling(self):
crawling = self.tocrawl.pop()
url = urlparse(crawling)
self.crawled.add(crawling)
request = Request(crawling,
headers={"User-Agent": config.crawler_user_agent})
try:
response = urlopen(request)
except Exception as e:
if hasattr(e, 'code'):
if e.code in self.response_code:
self.response_code[e.code] += 1
else:
self.response_code[e.code] = 1
# Gestion des urls marked pour le reporting
if self.report:
if e.code in self.marked:
self.marked[e.code].append(crawling)
else:
self.marked[e.code] = [crawling]
logging.debug("{1} ==> {0}".format(e, crawling))
return self.__continue_crawling()
# Read the response
try:
msg = response.read()
if response.getcode() in self.response_code:
self.response_code[response.getcode()] += 1
else:
self.response_code[response.getcode()] = 1
response.close()
# Get the last modify date
if 'last-modified' in response.headers:
date = response.headers['Last-Modified']
else:
date = response.headers['Date']
date = datetime.strptime(date, '%a, %d %b %Y %H:%M:%S %Z')
except Exception as e:
logging.debug("{1} ===> {0}".format(e, crawling))
return None
print("<url><loc>" + url.geturl() + "</loc><lastmod>" +
date.strftime('%Y-%m-%dT%H:%M:%S+00:00') + "</lastmod></url>",
file=self.output_file)
if self.output_file:
self.output_file.flush()
# Found links
links = self.linkregex.findall(msg)
for link in links:
link = link.decode("utf-8")
#logging.debug("Found : {0}".format(link))
if link.startswith('/'):
link = 'http://' + url[1] + link
elif link.startswith('#'):
link = 'http://' + url[1] + url[2] + link
elif not link.startswith('http'):
link = 'http://' + url[1] + '/' + link
# Remove the anchor part if needed
if "#" in link:
link = link[:link.index('#')]
# Drop attributes if needed
for toDrop in self.drop:
link = re.sub(toDrop, '', link)
# Parse the url to get domain and file extension
parsed_link = urlparse(link)
domain_link = parsed_link.netloc
target_extension = os.path.splitext(parsed_link.path)[1][1:]
if (link in self.crawled):
continue
if (link in self.tocrawl):
continue
if (link in self.excluded):
continue
if (domain_link != self.target_domain):
continue
if ("javascript" in link):
continue
# Count one more URL
self.nb_url += 1
# Check if the navigation is allowed by the robots.txt
if (not self.can_fetch(link)):
self.exclude_link(link)
self.nb_rp += 1
continue
# Check if the current file extension is allowed or not.
if (target_extension in self.skipext):
self.exclude_link(link)
self.nb_exclude += 1
continue
# Check if the current url doesn't contain an excluded word
if (not self.exclude_url(link)):
self.exclude_link(link)
self.nb_exclude += 1
continue
self.tocrawl.add(link)
return None
def __continue_crawling(self):
if self.tocrawl:
self.__crawling()
def exclude_link(self, link):
if link not in self.excluded:
self.excluded.add(link)
def checkRobots(self):
if self.domain[len(self.domain) - 1] != "/":
self.domain += "/"
request = Request(self.domain + "robots.txt",
headers={"User-Agent": config.crawler_user_agent})
self.rp = RobotFileParser()
self.rp.set_url(self.domain + "robots.txt")
self.rp.read()
def can_fetch(self, link):
try:
if self.parserobots:
if self.rp.can_fetch("*", link):
return True
else:
logging.debug(
"Crawling of {0} disabled by robots.txt".format(link))
return False
if not self.parserobots:
return True
return True
except:
# On error continue!
logging.debug("Error during parsing robots.txt")
return True
def exclude_url(self, link):
for ex in self.exclude:
if ex in link:
return False
return True
def make_report(self):
print("Number of found URL : {0}".format(self.nb_url))
print("Number of link crawled : {0}".format(len(self.crawled)))
if self.parserobots:
print("Number of link block by robots.txt : {0}".format(
self.nb_rp))
if self.skipext or self.exclude:
print("Number of link exclude : {0}".format(self.nb_exclude))
for code in self.response_code:
print("Nb Code HTTP {0} : {1}".format(code,
self.response_code[code]))
for code in self.marked:
print("Link with status {0}:".format(code))
for uri in self.marked[code]:
print("\t- {0}".format(uri))
class Crawler():
# Variables
parserobots = False
output = None
report = False
config = None
domain = ""
exclude = []
skipext = []
drop = []
debug = False
tocrawl = set([])
crawled = set([])
excluded = set([])
marked = {}
not_parseable_ressources = (".epub", ".mobi", ".docx", ".doc", ".opf", ".7z", ".ibooks", ".cbr", ".avi", ".mkv", ".mp4", ".jpg", ".jpeg", ".png", ".gif" ,".pdf", ".iso", ".rar", ".tar", ".tgz", ".zip", ".dmg", ".exe")
# TODO also search for window.location={.*?}
linkregex = re.compile(b'<a [^>]*href=[\'|"](.*?)[\'"][^>]*?>')
imageregex = re.compile (b'<img [^>]*src=[\'|"](.*?)[\'"].*?>')
rp = None
response_code={}
nb_url=1 # Number of url.
nb_rp=0 # Number of url blocked by the robots.txt
nb_exclude=0 # Number of url excluded by extension or word
output_file = None
target_domain = ""
scheme = ""
def __init__(self, parserobots=False, output=None, report=False ,domain="",
exclude=[], skipext=[], drop=[], debug=False, verbose=False, images=False):
self.parserobots = parserobots
self.output = output
self.report = report
self.domain = domain
self.exclude = exclude
self.skipext = skipext
self.drop = drop
self.debug = debug
self.verbose = verbose
self.images = images
if self.debug:
log_level = logging.DEBUG
elif self.verbose:
log_level = logging.INFO
else:
log_level = logging.ERROR
logging.basicConfig(level=log_level)
self.tocrawl = set([self.clean_link(domain)])
try:
url_parsed = urlparse(domain)
self.target_domain = url_parsed.netloc
self.scheme = url_parsed.scheme
except:
logging.error("Invalide domain")
raise ("Invalid domain")
if self.output:
try:
self.output_file = open(self.output, 'w')
except:
logging.error ("Output file not available.")
exit(255)
def run(self):
print(config.xml_header, file=self.output_file)
if self.parserobots:
self.check_robots()
logging.info("Start the crawling process")
while len(self.tocrawl) != 0:
self.__crawling(first,domainname,all_link)
logging.info("Crawling has reached end of all found links")
print (config.xml_footer, file=self.output_file)
def __crawling(self,frst,dmname,all_links):
crawling = self.tocrawl.pop()
if frst==0:
dmname=obtaindomain(crawling)
frst=1
url = urlparse(crawling)
self.crawled.add(crawling)
logging.info("Crawling #{}: {}".format(len(self.crawled), url.geturl()))
request = Request(crawling, headers={"User-Agent":config.crawler_user_agent})
# Ignore ressources listed in the not_parseable_ressources
# Its avoid dowloading file like pdf… etc
if not url.path.endswith(self.not_parseable_ressources):
try:
response = urlopen(request)
except Exception as e:
if hasattr(e,'code'):
if e.code in self.response_code:
self.response_code[e.code]+=1
else:
self.response_code[e.code]=1
# Gestion des urls marked pour le reporting
if self.report:
if e.code in self.marked:
self.marked[e.code].append(crawling)
else:
self.marked[e.code] = [crawling]
logging.debug ("{1} ==> {0}".format(e, crawling))
return self.__continue_crawling()
else:
logging.debug("Ignore {0} content might be not parseable.".format(crawling))
response = None
# Read the response
if response is not None:
try:
msg = response.read()
if response.getcode() in self.response_code:
self.response_code[response.getcode()]+=1
else:
self.response_code[response.getcode()]=1
response.close()
# Get the last modify date
if 'last-modified' in response.headers:
date = response.headers['Last-Modified']
else:
date = response.headers['Date']
date = datetime.strptime(date, '%a, %d %b %Y %H:%M:%S %Z')
except Exception as e:
logging.debug ("{1} ===> {0}".format(e, crawling))
return None
else:
# Response is None, content not downloaded, just continu and add
# the link to the sitemap
msg = "".encode( )
date = None
# Image sitemap enabled ?
image_list = "";
if self.images:
# Search for images in the current page.
images = self.imageregex.findall(msg)
for image_link in list(set(images)):
image_link = image_link.decode("utf-8", errors="ignore")
# Ignore link starting with data:
if image_link.startswith("data:"):
continue
# If path start with // get the current url scheme
if image_link.startswith("//"):
image_link = url.scheme + ":" + image_link
# Append domain if not present
elif not image_link.startswith(("http", "https")):
if not image_link.startswith("/"):
image_link = "/{0}".format(image_link)
image_link = "{0}{1}".format(self.domain.strip("/"), image_link.replace("./", "/"))
# Ignore image if path is in the exclude_url list
if not self.exclude_url(image_link):
continue
# Ignore other domain images
image_link_parsed = urlparse(image_link)
if image_link_parsed.netloc != self.target_domain:
continue
# Test if images as been already seen and not present in the
# robot file
if self.can_fetch(image_link):
logging.debug("Found image : {0}".format(image_link))
image_list = "{0}<image:image><image:loc>{1}</image:loc></image:image>".format(image_list, self.htmlspecialchars(image_link))
# Last mod fetched ?
lastmod = ""
if date:
lastmod = "<lastmod>"+date.strftime('%Y-%m-%dT%H:%M:%S+00:00')+"</lastmod>"
print ("<url><loc>"+self.htmlspecialchars(url.geturl())+"</loc>" + lastmod + image_list + "</url>", file=self.output_file)
tempdom=obtaindomain(self.htmlspecialchars(url.geturl()))
templink=self.htmlspecialchars(url.geturl())
if tempdom==dmname:
if templink not in all_links:
outputprint(templink)
all_links.append(templink)
if self.output_file:
self.output_file.flush()
# Found links
links = self.linkregex.findall(msg)
for link in links:
link = link.decode("utf-8", errors="ignore")
link = self.clean_link(link)
logging.debug("Found : {0}".format(link))
if link.startswith('/'):
link = url.scheme + '://' + url[1] + link
elif link.startswith('#'):
link = url.scheme + '://' + url[1] + url[2] + link
elif link.startswith(("mailto", "tel")):
continue
elif not link.startswith(('http', "https")):
link = url.scheme + '://' + url[1] + '/' + link
# Remove the anchor part if needed
if "#" in link:
link = link[:link.index('#')]
# Drop attributes if needed
for toDrop in self.drop:
link=re.sub(toDrop,'',link)
# Parse the url to get domain and file extension
parsed_link = urlparse(link)
domain_link = parsed_link.netloc
target_extension = os.path.splitext(parsed_link.path)[1][1:]
if link in self.crawled:
continue
if link in self.tocrawl:
continue
if link in self.excluded:
continue
if domain_link != self.target_domain:
continue
if parsed_link.path in ["", "/"]:
continue
if "javascript" in link:
continue
if self.is_image(parsed_link.path):
continue
if parsed_link.path.startswith("data:"):
continue
# Count one more URL
self.nb_url+=1
# Check if the navigation is allowed by the robots.txt
if not self.can_fetch(link):
self.exclude_link(link)
self.nb_rp+=1
continue
# Check if the current file extension is allowed or not.
if (target_extension in self.skipext):
self.exclude_link(link)
self.nb_exclude+=1
continue
# Check if the current url doesn't contain an excluded word
if (not self.exclude_url(link)):
self.exclude_link(link)
self.nb_exclude+=1
continue
self.tocrawl.add(link)
return None
def clean_link(self, link):
l = urlparse(link)
l_res = list(l)
l_res[2] = l_res[2].replace("./", "/")
l_res[2] = l_res[2].replace("//", "/")
return urlunparse(l_res)
def is_image(self, path):
mt,me = mimetypes.guess_type(path)
return mt is not None and mt.startswith("image/")
def __continue_crawling(self):
if self.tocrawl:
self.__crawling(first,domainname,all_link)
def exclude_link(self,link):
if link not in self.excluded:
self.excluded.add(link)
def check_robots(self):
robots_url = urljoin(self.domain, "robots.txt")
self.rp = RobotFileParser()
self.rp.set_url(robots_url)
self.rp.read()
def can_fetch(self, link):
try:
if self.parserobots:
if self.rp.can_fetch("*", link):
return True
else:
logging.debug ("Crawling of {0} disabled by robots.txt".format(link))
return False
if not self.parserobots:
return True
return True
except:
# On error continue!
logging.debug ("Error during parsing robots.txt")
return True
def exclude_url(self, link):
for ex in self.exclude:
if ex in link:
return False
return True
def htmlspecialchars(self, text):
return text.replace("&", "&").replace('"', """).replace("<", "<").replace(">", ">")
def make_report(self):
print ("Number of found URL : {0}".format(self.nb_url))
print ("Number of link crawled : {0}".format(len(self.crawled)))
if self.parserobots:
print ("Number of link block by robots.txt : {0}".format(self.nb_rp))
if self.skipext or self.exclude:
print ("Number of link exclude : {0}".format(self.nb_exclude))
for code in self.response_code:
print ("Nb Code HTTP {0} : {1}".format(code, self.response_code[code]))
for code in self.marked:
print ("Link with status {0}:".format(code))
for uri in self.marked[code]:
print ("\t- {0}".format(uri))
class Crawler():
# Variables
parserobots = False
output = None
report = False
config = None
domain = ""
exclude = []
skipext = []
drop = []
debug = False
tocrawl = set([])
crawled = set([])
excluded = set([])
# TODO also search for window.location={.*?}
linkregex = re.compile(b'<a href=[\'|"](.*?)[\'"].*?>')
rp = None
response_code={}
nb_url=1 # Number of url.
nb_rp=0 # Number of url blocked by the robots.txt
nb_exclude=0 # Number of url excluded by extension or word
output_file = None
target_domain = ""
def __init__(self, parserobots=False, output=None, report=False ,domain="", exclude=[], skipext=[], drop=[], debug=False):
self.parserobots = parserobots
self.output = output
self.report = report
self.domain = domain
self.exclude = exclude
self.skipext = skipext
self.drop = drop
self.debug = debug
if self.debug:
logging.basicConfig(level=logging.DEBUG)
self.tocrawl = set([domain])
try:
self.target_domain = urlparse(domain)[1]
except:
raise ("Invalid domain")
if self.output:
try:
self.output_file = open(self.output, 'w')
except:
logging.debug ("Output file not available.")
exit(255)
def run(self):
print (config.xml_header, file=self.output_file)
logging.debug("Start the crawling process")
self.__crawling()
logging.debug("Crawling as reach the end of all found link")
print (config.xml_footer, file=self.output_file)
def __crawling(self):
crawling = self.tocrawl.pop()
url = urlparse(crawling)
self.crawled.add(crawling)
request = Request(crawling, headers={"User-Agent":config.crawler_user_agent})
try:
response = urlopen(request)
except Exception as e:
if hasattr(e,'code'):
if e.code in self.response_code:
self.response_code[e.code]+=1
else:
self.response_code[e.code]=1
logging.debug ("{1} ==> {0}".format(e, crawling))
return self.__continue_crawling()
# Read the response
try:
msg = response.read()
if response.getcode() in self.response_code:
self.response_code[response.getcode()]+=1
else:
self.response_code[response.getcode()]=1
response.close()
# Get the last modify date
if 'last-modified' in response.headers:
date = response.headers['Last-Modified']
else:
date = response.headers['Date']
date = datetime.strptime(date, '%a, %d %b %Y %H:%M:%S %Z')
except Exception as e:
logging.debug ("{1} ===> {0}".format(e, crawling))
return self.__continue_crawling()
print ("<url><loc>"+url.geturl()+"</loc><lastmod>"+date.strftime('%Y-%m-%dT%H:%M:%S')+"</lastmod></url>", file=self.output_file)
if self.output_file:
self.output_file.flush()
# Found links
links = self.linkregex.findall(msg)
for link in links:
link = link.decode("utf-8")
#logging.debug("Found : {0}".format(link))
if link.startswith('/'):
link = 'http://' + url[1] + link
elif link.startswith('#'):
link = 'http://' + url[1] + url[2] + link
elif not link.startswith('http'):
link = 'http://' + url[1] + '/' + link
# Remove the anchor part if needed
if "#" in link:
link = link[:link.index('#')]
# Drop attributes if needed
for toDrop in self.drop:
link=re.sub(toDrop,'',link)
# Parse the url to get domain and file extension
parsed_link = urlparse(link)
domain_link = parsed_link.netloc
target_extension = os.path.splitext(parsed_link.path)[1][1:]
if (link in self.crawled):
continue
if (link in self.tocrawl):
continue
if (link in self.excluded):
continue
if (domain_link != self.target_domain):
continue
if ("javascript" in link):
continue
# Count one more URL
self.nb_url+=1
# Check if the navigation is allowed by the robots.txt
if (not self.can_fetch(link)):
self.exclude_link(link)
self.nb_rp+=1
continue
# Check if the current file extension is allowed or not.
if (target_extension in self.skipext):
self.exclude_link(link)
self.nb_exclude+=1
continue
# Check if the current url doesn't contain an excluded word
if (not self.exclude_url(link)):
self.exclude_link(link)
self.nb_exclude+=1
continue
self.tocrawl.add(link)
return self.__continue_crawling()
def __continue_crawling(self):
if self.tocrawl:
self.__crawling()
def exclude_link(self,link):
if link not in self.excluded:
self.excluded.add(link)
def checkRobots(self):
if self.domain[len(self.domain)-1] != "/":
self.domain += "/"
request = Request(self.domain+"robots.txt", headers={"User-Agent":config.crawler_user_agent})
self.rp = RobotFileParser()
self.rp.set_url(self.domain+"robots.txt")
self.rp.read()
def can_fetch(self, link):
try:
if self.parserobots:
if self.rp.can_fetch("*", link):
return True
else:
logging.debug ("Crawling of {0} disabled by robots.txt".format(link))
return False
if not self.parserobots:
return True
return True
except:
# On error continue!
logging.debug ("Error during parsing robots.txt")
return True
def exclude_url(self, link):
for ex in self.exclude:
if ex in link:
return False
return True
def make_report(self):
print ("Number of found URL : {0}".format(self.nb_url))
print ("Number of link crawled : {0}".format(len(self.crawled)))
if self.parserobots:
print ("Number of link block by robots.txt : {0}".format(self.nb_rp))
if self.skipext or self.exclude:
print ("Number of link exclude : {0}".format(self.nb_exclude))
for code in self.response_code:
print ("Nb Code HTTP {0} : {1}".format(code, self.response_code[code]))
# 爬虫协议
from urllib.robotparser import RobotFileParser
rp = RobotFileParser()
rp.set_url('http://www.jianshu.com/robots.txt')
rp.read()
print(rp.mtime())
print(rp.can_fetch('*', 'http://www.jianshu.com/p/b67554025d7d'))
print(rp.can_fetch('*', "*"))
class _RobotAllowAll:
def can_fetch(self, a,b):
return True
class Robot:
def __init__(self):
self.__robots = {}
def can_fetch(self, url):
parse = urllib.parse.urlparse(url)
hostname = parse.hostname
try:
robot = self.robot[hostname]
except Exception:
roboturl = urllib.parse.urlunparse((parse.scheme,parse.netloc,"robots.txt","","",""))
robot = RobotFileParser(roboturl)
try:
robot.read()
except Exception:
robot = _RobotAllowAll()
self.__robots[hostname] = robot
return robot.can_fetch("*", url)
if __name__ == "__main__":
r = RobotFileParser("http://www.letudiant.fr", {})
r.read()
print(r.can_fetch("*", "http://www.letudiant.fr/"))
