Scrapy ignore request for a specific domain - python

I try to crawl the forum category of craiglist.org (https://forums.craigslist.org/).
My spider:
class CraigslistSpider(scrapy.Spider):
name = "craigslist"
allowed_domains = ["forums.craigslist.org"]
start_urls = ['http://geo.craigslist.org/iso/us/']
def error_handler(self, failure):
print failure
def parse(self, response):
yield Request('https://forums.craigslist.org/',
self.getForumPage,
dont_filter=True,
errback=self.error_handler)
def getForumPage(self, response):
print "forum page"
I have this message by the error callback:
[Failure instance: Traceback: :
/usr/local/lib/python2.7/site-packages/twisted/internet/defer.py:455:callback
/usr/local/lib/python2.7/site-packages/twisted/internet/defer.py:563:_startRunCallbacks
/usr/local/lib/python2.7/site-packages/twisted/internet/defer.py:649:_runCallbacks
/usr/local/lib/python2.7/site-packages/twisted/internet/defer.py:1316:gotResult
--- ---
/usr/local/lib/python2.7/site-packages/twisted/internet/defer.py:1258:_inlineCallbacks
/usr/local/lib/python2.7/site-packages/twisted/python/failure.py:389:throwExceptionIntoGenerator
/usr/local/lib/python2.7/site-packages/scrapy/core/downloader/middleware.py:37:process_request
/usr/local/lib/python2.7/site-packages/twisted/internet/defer.py:649:_runCallbacks
/usr/local/lib/python2.7/site-packages/scrapy/downloadermiddlewares/robotstxt.py:46:process_request_2
]
But i have this problem only with the forum section of Craigslist. It might be because is https for the forum section in contrary of the rest of website.
So, impossible to get a response...
An idea ?

I post a solution that I found for get around the problem.
I have used urllib2 library. Look:
import urllib2
from scrapy.http import HtmlResponse
class CraigslistSpider(scrapy.Spider):
name = "craigslist"
allowed_domains = ["forums.craigslist.org"]
start_urls = ['http://geo.craigslist.org/iso/us/']
def error_handler(self, failure):
print failure
def parse(self, response):
# Get a valid request with urllib2
req = urllib2.Request('https://forums.craigslist.org/')
# Get the content of this request
pageContent = urllib2.urlopen(req).read()
# Parse the content in a HtmlResponse compatible with Scrapy
response = HtmlResponse(url=response.url, body=pageContent)
print response.css(".forumlistcolumns li").extract()
With this solution, you can parse a good request in a valid Scrapy request and use this normaly.
There is probably a better method but this one is functional.

I think you are dealing with robots.txt. Try running your spider with
custom_settings = {
"ROBOTSTXT_OBEY": False
}
You can also test it using command line settings: scrapy crawl craigslist -s ROBOTSTXT_OBEY=False.

Related

Scrapy response url not exatly the same as the one i defined on start urls

I have a spider i give it this url https://tuskys.dpo.store/#!/~/search/keyword=dairy milk
However when i try to get the url in scrapy parse method the url looks like https://tuskys.dpo.store/?_escaped_fragment_=%2F%7E%2Fsearch%2Fkeyword%3Ddairy%2520milk
Here is a demo code to demonstrate my problem
import scrapy
class TuskysDpoSpider(scrapy.Spider):
name = "Tuskys_dpo"
#allowed_domains = ['ebay.com']
start_urls = ['https://tuskys.dpo.store/#!/~/search/keyword=dairy milk']
def parse(self, response):
yield{'url':response.url}
results: {"url": "https://tuskys.dpo.store/?_escaped_fragment_=%2F%7E%2Fsearch%2Fkeyword%3Ddairy%2520milk"}
Why is my scrapy response url not exactly the same as the url i defined and is there a way to go around this?
You should use response.request.url because you are redirected from your start url, so response.url is the url you are redirected to.

Can't get all http requests in Scrapy

I'm trying to access a site and check if no links redirecting to a page within the site that are down. As there is no sitemap available, I'm using Scrapy to crawl the site and get all links on every page, but I can't get it to output a file with all the links found and their status code. The site I'm using to test the code is quotes.toscrape.com and my code is:
from scrapy.spiders import Spider
from mytest.items import MytestItem
from scrapy.http
import Request
import re
class MySpider(Spider):
name = "sample"
allowed_domains = ["quotes.toscrape.com"]
start_urls = ["http://quotes.toscrape.com"]
def parse(self, response):
links = response.xpath('//a/#href').extract()
\# We stored already crawled links in this list
crawledLinks = []
for link in links:
\# If it is a proper link and is not checked yet, yield it to the Spider
if link not in crawledLinks:
link = "http://quotes.toscrape.com" + link
crawledLinks.append(link)
yield Request(link, self.parse)
I've tried adding the following lines after yield:
item = MytestItem()
item['url'] = link
item['status'] = response.status
yield item
But it gets me a bunch of duplicates and no url with status 404 or 301. Does anyone know how I can get all the urls with the status?
Scrapy by default does not return any unsuccessful requests, but you can fetch them and handle them in one of your functions if you set errback on the request.
def parse(self, response):
# some code
yield Request(link, self.parse, errback=self.parse_error)
def parse_error(self, failure):
# log the response as an error
The parameter failure will contain more information on the exact reason for failure, because it could be HTTP errors (where you can fetch a response), but also DNS lookup errors and such (where there is no response).
The documentation contains an example how to use failure to determine the error reason and access Response if available:
def errback_httpbin(self, failure):
# log all failures
self.logger.error(repr(failure))
# in case you want to do something special for some errors,
# you may need the failure's type:
if failure.check(HttpError):
# these exceptions come from HttpError spider middleware
# you can get the non-200 response
response = failure.value.response
self.logger.error('HttpError on %s', response.url)
elif failure.check(DNSLookupError):
# this is the original request
request = failure.request
self.logger.error('DNSLookupError on %s', request.url)
elif failure.check(TimeoutError, TCPTimedOutError):
request = failure.request
self.logger.error('TimeoutError on %s', request.url)
You should use the HTTPERROR_ALLOW_ALL in your settings or set the meta key handle_httpstatus_all = Truein all your requests, please refer to the docs for more information.

Scrapy callback after redirect

I have a very basic scrapy spider, which grabs urls from the file and then downloads them. The only problem is that some of them got redirected to a slightly modified url within same domain. I want to get them in my callback function using response.meta, and it works on a normal urls, but then url is redirected callback doesn't seem to get called. How can I fix it?
Here's my code.
from scrapy.contrib.spiders import CrawlSpider
from scrapy import log
from scrapy import Request
class DmozSpider(CrawlSpider):
name = "dmoz"
handle_httpstatus_list = [302]
allowed_domains = ["http://www.exmaple.net/"])
f = open("C:\\python27\\1a.csv",'r')
url = 'http://www.exmaple.net/Query?indx='
start_urls = [url+row for row in f.readlines()]
def parse(self, response):
print response.meta.get('redirect_urls', [response.url])
print response.status
print (response.headers.get('Location'))
I've also tried something like that:
def parse(self, response):
return Request(response.url, meta={'dont_redirect': True, 'handle_httpstatus_list': [302]}, callback=self.parse_my_url)
def parse_my_url(self, response):
print response.status
print (response.headers.get('Location'))
And it doesn't work either.
By default scrapy requests are redirected, although if you don't want to redirect you can do like this, use start_requests method and add flags in request meta.
def start_requests(self):
requests =[(Request(self.url+u, meta={'handle_httpstatus_list': [302],
'dont_redirect': True},
callback=self.parse)) for u in self.start_urls]
return requests

Failed to crawl element of specific website with scrapy spider

I want to get website addresses of some jobs, so I write a scrapy spider, I want to get all of the value with xpath://article/dl/dd/h2/a[#class="job-title"]/#href, but when I execute the spider with command :
scrapy spider auseek -a addsthreshold=3
the variable "urls" used to preserve values is empty, can someone help me to figure it,
here is my code:
from scrapy.contrib.spiders import CrawlSpider,Rule
from scrapy.selector import Selector
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.conf import settings
from scrapy.mail import MailSender
from scrapy.xlib.pydispatch import dispatcher
from scrapy.exceptions import CloseSpider
from scrapy import log
from scrapy import signals
from myProj.items import ADItem
import time
class AuSeekSpider(CrawlSpider):
name = "auseek"
result_address = []
addressCount = int(0)
addressThresh = int(0)
allowed_domains = ["seek.com.au"]
start_urls = [
"http://www.seek.com.au/jobs/in-australia/"
]
def __init__(self,**kwargs):
super(AuSeekSpider, self).__init__()
self.addressThresh = int(kwargs.get('addsthreshold'))
print 'init finished...'
def parse_start_url(self,response):
print 'This is start url function'
log.msg("Pipeline.spider_opened called", level=log.INFO)
hxs = Selector(response)
urls = hxs.xpath('//article/dl/dd/h2/a[#class="job-title"]/#href').extract()
print 'urls is:',urls
print 'test element:',urls[0].encode("ascii")
for url in urls:
postfix = url.getAttribute('href')
print 'postfix:',postfix
url = urlparse.urljoin(response.url,postfix)
yield Request(url, callback = self.parse_ad)
return
def parse_ad(self, response):
print 'this is parse_ad function'
hxs = Selector(response)
item = ADItem()
log.msg("Pipeline.parse_ad called", level=log.INFO)
item['name'] = str(self.name)
item['picNum'] = str(6)
item['link'] = response.url
item['date'] = time.strftime('%Y%m%d',time.localtime(time.time()))
self.addressCount = self.addressCount + 1
if self.addressCount > self.addressThresh:
raise CloseSpider('Get enough website address')
return item
The problems is:
urls = hxs.xpath('//article/dl/dd/h2/a[#class="job-title"]/#href').extract()
urls is empty when I tried to print it out, I just cant figure out why it doesn't work and how can I correct it, thanks for your help.
Here is a working example using selenium and phantomjs headless webdriver in a download handler middleware.
class JsDownload(object):
#check_spider_middleware
def process_request(self, request, spider):
driver = webdriver.PhantomJS(executable_path='D:\phantomjs.exe')
driver.get(request.url)
return HtmlResponse(request.url, encoding='utf-8', body=driver.page_source.encode('utf-8'))
I wanted to ability to tell different spiders which middleware to use so I implemented this wrapper:
def check_spider_middleware(method):
#functools.wraps(method)
def wrapper(self, request, spider):
msg = '%%s %s middleware step' % (self.__class__.__name__,)
if self.__class__ in spider.middleware:
spider.log(msg % 'executing', level=log.DEBUG)
return method(self, request, spider)
else:
spider.log(msg % 'skipping', level=log.DEBUG)
return None
return wrapper
settings.py:
DOWNLOADER_MIDDLEWARES = {'MyProj.middleware.MiddleWareModule.MiddleWareClass': 500}
for wrapper to work all spiders must have at minimum:
middleware = set([])
to include a middleware:
middleware = set([MyProj.middleware.ModuleName.ClassName])
You could have implemented this in a request callback (in spider) but then the http request would be happening twice. This isn't a full proof solution but it works for stuff that loads on .ready(). If you spend some time reading into selenium you can wait for specific event's to trigger before saving page source.
Another example: https://github.com/scrapinghub/scrapyjs
More info: What's the best way of scraping data from a website?
Cheers!
Scrapy does not evaluate Javascript. If you run the following command, you will see that the raw HTML does not contain the anchors you are looking for.
curl http://www.seek.com.au/jobs/in-australia/ | grep job-title
You should try PhantomJS or Selenium instead.
After examining the network requests in Chrome, the job listing appear to have originated from this JSONP request. It should be easy to retrieve whatever you need from it.

Scrapy: Creating a Request to a site that is not in allowed_domains

I am scraping a certain website. Under certain conditions, I might want to make a Request to go to a website that is not listed in allowed_domains. Is that possible? If not, can I temporarily add the domain in there, create a Request and then remove the domain from my parser callback?
Set dont_filter=True on a Request object (documentation):
dont_filter (boolean) – indicates that this request should not be
filtered by the scheduler.
Example:
from scrapy.spider import BaseSpider
from scrapy.http import Request
class MySpider(BaseSpider):
name = 'wikipedia'
allowed_domains = ['en.wikipedia.org']
start_urls = [
'http://en.wikipedia.org/wiki/Main_Page',
]
def parse(self, response):
print "I'm at wikipedia"
request = Request(url="https://google.com",
callback=self.parse_google,
dont_filter=True)
yield request
def parse_google(self, response):
print "I'm at google"

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