I'm using scrapy to extract data from certain websites.The problem is that my spider can only crawl the webpage of initial start_urls , it can't crawl the urls in the webpage.
I copied the same spider exactly:
from scrapy.spider import BaseSpider
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import HtmlXPathSelector
from scrapy.http import Request
from scrapy.utils.response import get_base_url
from scrapy.utils.url import urljoin_rfc
from nextlink.items import NextlinkItem
class Nextlink_Spider(BaseSpider):
name = "Nextlink"
allowed_domains = ["Nextlink"]
start_urls = ["http://www.dmoz.org/Computers/Programming/Languages/Python/Books/"]
def parse(self, response):
hxs = HtmlXPathSelector(response)
sites = hxs.select('//body/div[2]/div[3]/div/ul/li[2]/a/#href')
for site in sites:
relative_url = site.extract()
url = self._urljoin(response,relative_url)
yield Request(url, callback = self.parsetext)
def parsetext(self, response):
log = open("log.txt", "a")
log.write("test if the parsetext is called")
hxs = HtmlXPathSelector(response)
items = []
texts = hxs.select('//div').extract()
for text in texts:
item = NextlinkItem()
item['text'] = text
items.append(item)
log = open("log.txt", "a")
log.write(text)
return items
def _urljoin(self, response, url):
"""Helper to convert relative urls to absolute"""
return urljoin_rfc(response.url, url, response.encoding)
I use the log.txt to test if the parsetext is called.However, after I runned my spider, there is nothing in the log.txt.
See here:
http://readthedocs.org/docs/scrapy/en/latest/topics/spiders.html?highlight=allowed_domains#scrapy.spider.BaseSpider.allowed_domains
allowed_domains
An optional list of strings containing domains that this spider is allowed to crawl. Requests for URLs not belonging to the domain names specified in this list won’t be followed if OffsiteMiddleware is enabled.
So, as long as you didn't activate the OffsiteMiddleware in your settings, it doesn't matter and you can leave allowed_domains completely out.
Check the settings.py whether the OffsiteMiddleware is activated or not. It shouldn't be activated if you want to allow your Spider to crawl on any domain.
I think the problem is, that you didn't tell Scrapy to follow each crawled URL. For my own blog I've implemented a CrawlSpider that uses LinkExtractor-based Rules to extract all relevant links from my blog pages:
# -*- coding: utf-8 -*-
'''
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* #author Marcel Lange <info#ask-sheldon.com>
* #package ScrapyCrawler
'''
from scrapy.spiders import CrawlSpider, Rule
from scrapy.linkextractors import LinkExtractor
import Crawler.settings
from Crawler.items import PageCrawlerItem
class SheldonSpider(CrawlSpider):
name = Crawler.settings.CRAWLER_NAME
allowed_domains = Crawler.settings.CRAWLER_DOMAINS
start_urls = Crawler.settings.CRAWLER_START_URLS
rules = (
Rule(
LinkExtractor(
allow_domains=Crawler.settings.CRAWLER_DOMAINS,
allow=Crawler.settings.CRAWLER_ALLOW_REGEX,
deny=Crawler.settings.CRAWLER_DENY_REGEX,
restrict_css=Crawler.settings.CSS_SELECTORS,
canonicalize=True,
unique=True
),
follow=True,
callback='parse_item',
process_links='filter_links'
),
)
# Filter links with the nofollow attribute
def filter_links(self, links):
return_links = list()
if links:
for link in links:
if not link.nofollow:
return_links.append(link)
else:
self.logger.debug('Dropped link %s because nofollow attribute was set.' % link.url)
return return_links
def parse_item(self, response):
# self.logger.info('Parsed URL: %s with STATUS %s', response.url, response.status)
item = PageCrawlerItem()
item['status'] = response.status
item['title'] = response.xpath('//title/text()')[0].extract()
item['url'] = response.url
item['headers'] = response.headers
return item
On https://www.ask-sheldon.com/build-a-website-crawler-using-scrapy-framework/ I've described detailed how I've implemented a website crawler to warm up my Wordpress fullpage cache.
My guess would be this line:
allowed_domains = ["Nextlink"]
This isn't a domain like domain.tld, so it would reject any links.
If you take the example from the documentation: allowed_domains = ["dmoz.org"]
Related
I need to make absolute urls out of these relative urls. Tried to use process_links but in vain. Any suggestions?
# -*- coding: utf-8 -*-
import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule
class FfySpider(CrawlSpider):
name = 'FFy'
allowed_domains = ['cartoon3rbi.net']
start_urls = ['https://www.cartoon3rbi.net/cats-pages-1.html/']
rules = (
Rule(LinkExtractor(restrict_xpaths='//div[#class="cartoon_cat_name"]'), process_links='make_absolute_path',
callback='parse_item', follow=True),
)
def parse_item(self, response):
yield {
'name': response.xpath('//div[#class="cartoon_eps_name"]/a/text()[2]').extract(),
}
def make_absolute_path(self, links):
for link in links:
url = 'https://www.cartoon3rbi.net/' + link
return url
From scrapy documentation:
https://docs.scrapy.org/en/latest/topics/spiders.html#crawling-rules
process_links is a callable, or a string (in which case a method from the spider object with that name will be used) which will be called for each list of links extracted from each response using the specified link_extractor. This is mainly used for filtering purposes.
I think function specified by process_links is called with a list of links and should be returning a list of links (or a generator).
def make_absolute_path(self, links):
for link in links:
url = 'https://www.cartoon3rbi.net/' + link
yield url
This is my first question here and I'm learning how to code by myself so please bear with me.
I'm working on a final CS50 project which I'm trying to built a website that aggregates online Spanish course from edx.org and other open online couses websites maybe. I'm using scrapy framework to scrap the filter results of Spanish courses on edx.org... Here is my first scrapy spider which I'm trying to get in each courses link to then get it's name (after I get the code right, also get the description, course url and more stuff).
from scrapy.item import Field, Item
from scrapy.spiders import CrawlSpider, Rule
from scrapy.linkextractor import LinkExtractor
from scrapy.loader import ItemLoader
class Course_item(Item):
name = Field()
#description = Field()
#img_url = Field()
class Course_spider(CrawlSpider):
name = 'CourseSpider'
allowed_domains = ['https://www.edx.org/']
start_urls = ['https://www.edx.org/course/?language=Spanish']
rules = (Rule(LinkExtractor(allow=r'/course'), callback='parse_item', follow='True'),)
def parse_item(self, response):
item = ItemLoader(Course_item, response)
item.add_xpath('name', '//*[#id="course-intro-heading"]/text()')
yield item.load_item()
When I run the spider with "scrapy runspider edxSpider.py -o edx.csv -t csv" I get an empty csv file and I also think is not getting into the right spanish courses results.
Basically I want to get in each courses of this link edx Spanish courses and get the name, description, provider, page url and img url.
Any ideas for why might be the problem?
You can't get edx content with a simple request, it uses javascript rendering for getting the course element dynamically, so CrawlSpider won't work on this case, because you need to find specific elements inside the response body to generate a new Request that will get what you need.
The real request (to get the urls of the courses) is this one, but you need to generate it from the previous response body (although you could just visit it an also get the correct data).
So, to generate the real request, you need data that is inside a script tag:
from scrapy import Spider
import re
import json
class Course_spider(Spider):
name = 'CourseSpider'
allowed_domains = ['edx.org']
start_urls = ['https://www.edx.org/course/?language=Spanish']
def parse(self, response):
script_text = response.xpath('//script[contains(text(), "Drupal.settings")]').extract_first()
parseable_json_data = re.search(r'Drupal.settings, ({.+})', script_text).group(1)
json_data = json.loads(parseable_json_data)
...
Now you have what you need on json_data and only need to create the string URL.
This page use JavaScript to get data from server and add to page.
It uses urls like
https://www.edx.org/api/catalog/v2/courses/course-v1:IDBx+IDB33x+3T2017
Last part is course's number which you can find in HTML
<main id="course-info-page" data-course-id="course-v1:IDBx+IDB33x+3T2017">
Code
from scrapy.http import Request
from scrapy.item import Field, Item
from scrapy.spiders import CrawlSpider, Rule
from scrapy.linkextractor import LinkExtractor
from scrapy.loader import ItemLoader
import json
class Course_spider(CrawlSpider):
name = 'CourseSpider'
allowed_domains = ['www.edx.org']
start_urls = ['https://www.edx.org/course/?language=Spanish']
rules = (Rule(LinkExtractor(allow=r'/course'), callback='parse_item', follow='True'),)
def parse_item(self, response):
print('parse_item url:', response.url)
course_id = response.xpath('//*[#id="course-info-page"]/#data-course-id').extract_first()
if course_id:
url = 'https://www.edx.org/api/catalog/v2/courses/' + course_id
yield Request(url, callback=self.parse_json)
def parse_json(self, response):
print('parse_json url:', response.url)
item = json.loads(response.body)
return item
from scrapy.crawler import CrawlerProcess
c = CrawlerProcess({
'USER_AGENT': 'Mozilla/5.0',
'FEED_FORMAT': 'csv', # csv, json, xml
'FEED_URI': 'output.csv', #
})
c.crawl(Course_spider)
c.start()
from scrapy.http import Request
from scrapy import Spider
import json
class edx_scraper(Spider):
name = "edxScraper"
start_urls = [
'https://www.edx.org/api/v1/catalog/search?selected_facets[]=content_type_exact%3Acourserun&selected_facets[]=language_exact%3ASpanish&page=1&page_size=9&partner=edx&hidden=0&content_type[]=courserun&content_type[]=program&featured_course_ids=course-v1%3AHarvardX+CS50B+Business%2Ccourse-v1%3AMicrosoft+DAT206x+1T2018%2Ccourse-v1%3ALinuxFoundationX+LFS171x+3T2017%2Ccourse-v1%3AHarvardX+HDS2825x+1T2018%2Ccourse-v1%3AMITx+6.00.1x+2T2017_2%2Ccourse-v1%3AWageningenX+NUTR101x+1T2018&featured_programs_uuids=452d5bbb-00a4-4cc9-99d7-d7dd43c2bece%2Cbef7201a-6f97-40ad-ad17-d5ea8be1eec8%2C9b729425-b524-4344-baaa-107abdee62c6%2Cfb8c5b14-f8d2-4ae1-a3ec-c7d4d6363e26%2Ca9cbdeb6-5fc0-44ef-97f7-9ed605a149db%2Cf977e7e8-6376-400f-aec6-84dcdb7e9c73'
]
def parse(self, response):
data = json.loads(response.text)
for course in data['objects']['results']:
url = 'https://www.edx.org/api/catalog/v2/courses/' + course['key']
yield response.follow(url, self.course_parse)
if 'next' in data['objects'] is not None:
yield response.follow(data['objects']['next'], self.parse)
def course_parse(self, response):
course = json.loads(response.text)
yield{
'name': course['title'],
'effort': course['effort'],
}
Hi can someone help me out I seem to be stuck, I am learning how to crawl and save into mysql us scrapy. I am trying to get scrapy to crawl all of the website pages. Starting with "start_urls", but it does not seem to automatically crawl all of the pages only the one, it does save into mysql with pipelines.py. It does also crawl all pages when provided with urls in a f = open("urls.txt") as well as saves data using pipelines.py.
here is my code
test.py
import scrapy
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.selector import HtmlXPathSelector
from gotp.items import GotPItem
from scrapy.log import *
from gotp.settings import *
from gotp.items import *
class GotP(CrawlSpider):
name = "gotp"
allowed_domains = ["www.craigslist.org"]
start_urls = ["http://sfbay.craigslist.org/search/sss"]
rules = [
Rule(SgmlLinkExtractor(
allow=('')),
callback ="parse",
follow=True
)
]
def parse(self, response):
hxs = HtmlXPathSelector(response)
prices = hxs.select("//div[#class="sliderforward arrow"]")
for price in prices:
item = GotPItem()
item ["price"] = price.select("text()").extract()
yield item
If I understand correctly, you are trying to follow the pagination and extract the results.
In this case, you can avoid using CrawlSpider and use regular Spider class.
The idea would be to parse the first page, extract total results count, calculate how much pages to go and yield scrapy.Request instances to the same URL providing s GET parameter value.
Implementation example:
import scrapy
class GotP(scrapy.Spider):
name = "gotp"
allowed_domains = ["www.sfbay.craigslist.org"]
start_urls = ["http://sfbay.craigslist.org/search/sss"]
results_per_page = 100
def parse(self, response):
total_count = int(response.xpath('//span[#class="totalcount"]/text()').extract()[0])
for page in xrange(0, total_count, self.results_per_page):
yield scrapy.Request("http://sfbay.craigslist.org/search/sss?s=%s&" % page, callback=self.parse_result, dont_filter=True)
def parse_result(self, response):
results = response.xpath("//p[#data-pid]")
for result in results:
try:
print result.xpath(".//span[#class='price']/text()").extract()[0]
except IndexError:
print "Unknown price"
This would follow the pagination and print prices on the console. Hope this is a good starting point.
I was trying to scrap link which has ajax call for pagination.
I am trying to crawl http://www.demo.com link. and in .py file I provided this code for restrict XPATH and coding is:
# -*- coding: utf-8 -*-
import scrapy
from scrapy.contrib.linkextractors import LinkExtractor
from scrapy.contrib.spiders import sumSpider, Rule
from scrapy.selector import HtmlXPathSelector
from sum.items import sumItem
class Sumspider1(sumSpider):
name = 'sumDetailsUrls'
allowed_domains = ['sum.com']
start_urls = ['http://www.demo.com']
rules = (
Rule(LinkExtractor(restrict_xpaths='.//ul[#id="pager"]/li[8]/a'), callback='parse_start_url', follow=True),
)
#use parse_start_url if your spider wants to crawl from first page , so overriding
def parse_start_url(self, response):
print '********************************************1**********************************************'
#//div[#class="showMoreCars hide"]/a
#.//ul[#id="pager"]/li[8]/a/#href
self.log('Inside - parse_item %s' % response.url)
hxs = HtmlXPathSelector(response)
item = sumItem()
item['page'] = response.url
title = hxs.xpath('.//h1[#class="page-heading"]/text()').extract()
print '********************************************title**********************************************',title
urls = hxs.xpath('.//a[#id="linkToDetails"]/#href').extract()
print '**********************************************2***url*****************************************',urls
finalurls = []
for url in urls:
print '---------url-------',url
finalurls.append(url)
item['urls'] = finalurls
return item
My items.py file contains
from scrapy.item import Item, Field
class sumItem(Item):
# define the fields for your item here like:
# name = scrapy.Field()
page = Field()
urls = Field()
Still I'm not getting exact output not able to fetch all pages when I am crawling it.
I hope the below code will help.
somespider.py
# -*- coding: utf-8 -*-
import scrapy
import re
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import Selector
from scrapy.spider import BaseSpider
from demo.items import DemoItem
from selenium import webdriver
def removeUnicodes(strData):
if(strData):
strData = strData.encode('utf-8').strip()
strData = re.sub(r'[\n\r\t]',r' ',strData.strip())
return strData
class demoSpider(scrapy.Spider):
name = "domainurls"
allowed_domains = ["domain.com"]
start_urls = ['http://www.domain.com/used/cars-in-trichy/']
def __init__(self):
self.driver = webdriver.Remote("http://127.0.0.1:4444/wd/hub", webdriver.DesiredCapabilities.HTMLUNITWITHJS)
def parse(self, response):
self.driver.get(response.url)
self.driver.implicitly_wait(5)
hxs = Selector(response)
item = DemoItem()
finalurls = []
while True:
next = self.driver.find_element_by_xpath('//div[#class="showMoreCars hide"]/a')
try:
next.click()
# get the data and write it to scrapy items
item['pageurl'] = response.url
item['title'] = removeUnicodes(hxs.xpath('.//h1[#class="page-heading"]/text()').extract()[0])
urls = self.driver.find_elements_by_xpath('.//a[#id="linkToDetails"]')
for url in urls:
url = url.get_attribute("href")
finalurls.append(removeUnicodes(url))
item['urls'] = finalurls
except:
break
self.driver.close()
return item
items.py
from scrapy.item import Item, Field
class DemoItem(Item):
page = Field()
urls = Field()
pageurl = Field()
title = Field()
Note:
You need to have selenium rc server running because HTMLUNITWITHJS works with selenium rc only using Python.
Run your selenium rc server issuing the command :
java -jar selenium-server-standalone-2.44.0.jar
Run your spider using command:
spider crawl domainurls -o someoutput.json
You can check with your browser how the requests are made.
Behind the scene, right after you click on that button "show more cars" your browser will request a JSON data to feed your next page. You can take advantage of this fact and deal directly with the JSON data without the necessity to work with a JavaScript engine as Selenium or PhantomJS.
In your case, as the first step you should simulate an user scrolling down the page given by your start_url parameter and profile at the same time your network requests to discover the endpoint used by the browser to request that JSON. To discover this endpoint in general there is a XHR(XMLHttpRequest) section on the browser's profile tool as here in Safari where you can navigate thought all resources/endpoints used to request the data.
Once you discover this endpoint it's a straightforward task: you give your Spider as start_url the endpoint that you just discovered and according you process and navigate through the JSON's you can discover if it a next page to request.
P.S.: I saw for you that the endpoint url is http://www.carwale.com/webapi/classified/stockfilters/?city=194&kms=0-&year=0-&budget=0-&pn=2
In this case my browser requested the second page, as you can see in the parameter pn. It's is important you set the some header parameters before you send the request. I noticed in your case the headers are:
Accept text/plain, /; q=0.01
Referer http://www.carwale.com/used/cars-in-trichy/
X-Requested-With XMLHttpRequest
sourceid 1
User-Agent Mozilla/5.0...
I am trying to crawl a website using Scrapy, and the urls of every page I want to scrap are all written using a relative path of this kind:
<!-- on page https://www.domain-name.com/en/somelist.html (no <base> in the <head>) -->
Link
Now, in my browser, these links work, and you get to urls like https://www.domain-name.com/en/item-to-scrap.html (despite the relative path going back up twice in hierarchy instead of once)
But my CrawlSpider does not manage to translate these urls into a "correct" one, and all I get is errors of that kind:
2013-10-13 09:30:41-0500 [domain-name.com] DEBUG: Retrying <GET https://www.domain-name.com/../en/item-to-scrap.html> (failed 1 times): 400 Bad Request
Is there a way to fix this, or am I missing something?
Here is my spider's code, fairly basic (on the basis of item urls matching "/en/item-*-scrap.html") :
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import HtmlXPathSelector
from scrapy.item import Item, Field
class Product(Item):
name = Field()
class siteSpider(CrawlSpider):
name = "domain-name.com"
allowed_domains = ['www.domain-name.com']
start_urls = ["https://www.domain-name.com/en/"]
rules = (
Rule(SgmlLinkExtractor(allow=('\/en\/item\-[a-z0-9\-]+\-scrap\.html')), callback='parse_item', follow=True),
Rule(SgmlLinkExtractor(allow=('')), follow=True),
)
def parse_item(self, response):
x = HtmlXPathSelector(response)
product = Product()
product['name'] = ''
name = x.select('//title/text()').extract()
if type(name) is list:
for s in name:
if s != ' ' and s != '':
product['name'] = s
break
return product
Basically deep down, scrapy uses http://docs.python.org/2/library/urlparse.html#urlparse.urljoin for getting the next url by joining currenturl and url link scrapped. And if you join the urls provided you mentioned as example,
<!-- on page https://www.domain-name.com/en/somelist.html -->
Link
the returned url is same as url mentioned in error scrapy error. Try this in python shell.
import urlparse
urlparse.urljoin("https://www.domain-name.com/en/somelist.html","../../en/item-to-scrap.html")
The urljoin behaviour seems to be valid. See : https://www.rfc-editor.org/rfc/rfc1808.html#section-5.2
If it is possible, can you pass the site, which you are crawling ?
With this understanding, the solutions can be,
Manipulate the urls(remove those two dots and slash). generated in crawl spider. Basically override parse or _request_to_folow.
Source of crawl spider: https://github.com/scrapy/scrapy/blob/master/scrapy/contrib/spiders/crawl.py
Manipulate the url in the downloadmiddleware, this might be cleaner. You remove the ../ in the process_request of the downloadmiddleware.
Documentation for downloadmiddleware : http://scrapy.readthedocs.org/en/0.16/topics/downloader-middleware.html
Use base spider and also return the manipulated url requests you want to crawl further
Documentation for the basespider : http://scrapy.readthedocs.org/en/0.16/topics/spiders.html#basespider
Please let me know if you have any questions.
I finally found a solution thanks to this answer. I used process_links as follows:
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import HtmlXPathSelector
from scrapy.item import Item, Field
class Product(Item):
name = Field()
class siteSpider(CrawlSpider):
name = "domain-name.com"
allowed_domains = ['www.domain-name.com']
start_urls = ["https://www.domain-name.com/en/"]
rules = (
Rule(SgmlLinkExtractor(allow=('\/en\/item\-[a-z0-9\-]+\-scrap\.html')), process_links='process_links', callback='parse_item', follow=True),
Rule(SgmlLinkExtractor(allow=('')), process_links='process_links', follow=True),
)
def parse_item(self, response):
x = HtmlXPathSelector(response)
product = Product()
product['name'] = ''
name = x.select('//title/text()').extract()
if type(name) is list:
for s in name:
if s != ' ' and s != '':
product['name'] = s
break
return product
def process_links(self,links):
for i, w in enumerate(links):
w.url = w.url.replace("../", "")
links[i] = w
return links