Develop Reference

Another Scrapy Question: Output to Console but not to .json

This is another newbie scrapy question:
When I first started with the scrapy tutorial linked here:
https://docs.scrapy.org/en/latest/intro/tutorial.html
I can crawl a webpage and then output the scraped content to a json file. But when I modify the tutorial to add a few rules like:
traversal depth
and memory so it doesn't traverse already visited pages again.
The output to the json stops although I can still see the output on the console. Can someone give me pointers on what I am doing wrong? The modifications can be seen below:
class QuotesSpider(scrapy.Spider):
name = "quotes"
#allowed_domains = allowed_domain_list
start_urls = input_domain_list
max_depth = 1
invalid_url = []
def parse(self, response):
from_url = ''
from_text = ''
depth = 0
# Extract the meta information from the response, if any
if 'text' in response.meta:
from_text = response.meta['text']
if 'depth' in response.meta:
depth = response.meta['depth']
if 'visited' in response.meta:
visited_dict = response.meta['visited']
else:
visited_dict = {}
if response.status == 404:
self.invalid_url.append(response.url)
print('*'*80)
print('INVALID LINK')
print('*'*80)
else:
page = response.url.split("/")[-2]
web_page = response.request.url
ext_text = ' '.join([item.strip() for item in
response.xpath('//body//text()').extract() if item.strip()])
visited = visited_dict.get('{0}'.format(web_page))
print('-'*80)
print('VALID LINK; Depth: {0}; Visited: {1}'.format(depth, visited))
print('-'*80)
yield {'text': ext_text,
'source': web_page}
if not visited and depth <= self.max_depth:
for selector in response.xpath('//a/#href'):
if selector is not None:
link = selector.get()
request = response.follow(link, callback=self.parse)
request.meta['visited'] = visited_dict
request.meta['visited'].update({'{0}'.format(web_page): 1})
request.meta['depth'] = depth + 1
print('*'*80)
print(link, request.meta['visited'])
print('*' * 80)
yield request

Scrapy - ValueError: Missing scheme in request url: #mw-head

I'm getting the following traceback but unsure how to refactor.
ValueError: Missing scheme in request url: #mw-head
Full code:
class MissleSpiderBio(scrapy.Spider):
name = 'missle_spider_bio'
allowed_domains = ['en.wikipedia.org']
start_urls = ['https://en.wikipedia.org/wiki/...']
this is the part giving me issues (I believe)
def parse(self, response):
filename = response.url.split('/')[-1]
table = response.xpath('///div/table[2]/tbody')
rows = table.xpath('//tr')
row = rows[2]
row.xpath('td//text()')[0].extract()
wdata = {}
for row in response.xpath('//* \
[#class="wikitable"]//tbody//tr'):
for link in response.xpath('//a/#href'):
link = link.extract()
if((link.strip() != '')):
yield Request(link, callback=self.parse)
#wdata.append(link)
else:
yield None
#wdata = {}
#wdata['link'] = BASE_URL +
#row.xpath('a/#href').extract() #[0]
wdata['link'] = BASE_URL + link
request = scrapy.Request(wdata['link'],\
callback=self.get_mini_bio, dont_filter=True)
request.meta['item'] = MissleItem(**wdata)
yield request
here is the second part of the code:
def get_mini_bio(self, response):
BASE_URL_ESCAPED = 'http:\/\/en.wikipedia.org'
item = response.meta['item']
item['image_urls'] = []
img_src = response.xpath('//table[contains(#class, \
"infobox")]//img/#src')
if img_src:
item['image_urls'] = ['http:' + img_src[0].extract()]
mini_bio = ''
paras = response.xpath('//*[#id="mw-content-text"]/p[text()\
or normalize-space(.)=""]').extract()
for p in paras:
if p =='<p></p>':
break
mini_bio += p
mini_bio = mini_bio.replace('href="/wiki', 'href="' + \
BASE_URL + '/wiki')
mini_bio = mini_bio.replace('href="#', item['link'] + '#')
item['mini_bio'] = mini_bio
yield item
I tried refactoring but am now getting a:
ValueError: Missing scheme in request url: #mw-head
any help would be immensely appreciated

Looks like you were on the right track with the commented out [0].
xpath().extract() #returns a list of strings
You need to select the string with [0]

row.xpath('a/#href').extract()
That expression evaluates to a list NOT a string. When you pass the URL to the request object, scrapy expects a string, not a list
To fix this, you have a few options:
You can use LinkExtractors which will allow you to search a page for links and automatically create scrapy request objects for those links:
https://doc.scrapy.org/en/latest/topics/link-extractors.html
OR
You could run a for loop and go through each of the links:
from scrapy.spiders import Request
for link in response.xpath('//a/#href'):
link = link.extract()
if((link.strip() != '')):
yield Request(link, callback=self.parse)
else:
yield None
You can add whatever string filters you want to that code
OR
If you just want the first link, you can use .extract_first() instead of .extract()

RegEx to get URLs from body string

So I was just wondering what my getURLs function's issue might be. I'm trying to get all urls from within the containing body's string.
My crawler isn't crawling anything because my input urls are invalid.
# Get all URLs contained within the body string
def getURLs(body):
urls = []
tempArr = body.split("a href=")
index = 1
for part in tempArr:
if part[0] == '"':
while (part[index] != '"' and index < len(part)):
index += 1
if index < len(part):
urls.append(part[1:index-1])
index = 1
return urls
# Open file which contains input urls
with open("test_urls.txt","rU") as infile:
urls = [row.strip("\n") for row in infile]
class BackpageSpider(CrawlSpider):
name = 'backpage'
allowed_domains = ['backpage.com']
start_urls = urls
def parse(self,response):
#print response.url
if response.status < 600:
# all_links = response.xpath("//div[contains(#class,'cat')]/a/#href").extract()
#all the links FOR THE ESCORTS on whatever page we're on
todays_links = []
#all the links for today's date
backpage_date = backpage_date_today()
yesterday_date = backpage_date_yesterday()
if backpage_date in response.body:
todays_section = response.body.split(backpage_date)[1].split(yesterday_date)[0].decode('utf-8')
# todays_links = todays_section.xpath("//div[contains(#class,'cat')]/a/#href").extract
todays_links = getURLs(todays_section)
# for url in todays_links:
# todays_links.append(url)
# for url in all_links:
# if url in todays_section:
# todays_links.append(url)
for url in todays_links:
yield scrapy.Request(url,callback=self.parse_ad_into_content)####HERE
for url in set(response.xpath('//a[#class="pagination next"]/#href').extract()):
yield scrapy.Request(url,callback=self.parse)
else:
time.sleep(600)
yield scrapy.Request(response.url,callback=self.parse)
def parse_ad_into_content(self,response):
#ipdb.set_trace()
item = items.BackpageScrapeItem(
url=response.url,
backpage_id=response.url.split('.')[0].split('/')[2].encode('utf-8'),
text = response.body,
posting_body= response.xpath("//div[#class='postingBody']").extract()[0].encode('utf-8'),
date = datetime.utcnow()-timedelta(hours=5),
posted_date = response.xpath("//div[#class='adInfo']/text()").extract()[0].encode('utf-8'),
posted_age = response.xpath("//p[#class='metaInfoDisplay']/text()").extract()[0].encode('utf-8'),
posted_title = response.xpath("//div[#id='postingTitle']//h1/text()").extract()[0].encode('utf-8')
)
return item
The web page is: http://grandisland.backpage.com/FemaleEscorts/?layout=date

Scrapy (Python): Iterating over 'next' page without multiple functions

I am using Scrapy to grab stock data from Yahoo! Finance.
Sometimes, I need to loop over several pages, 19 in this example , in order to get all of the stock data.
Previously (when I knew there would only be two pages), I would use one function for each page, like so:
def stocks_page_1(self, response):
returns_page1 = []
#Grabs data here...
current_page = response.url
next_page = current_page + "&z=66&y=66"
yield Request(next_page, self.stocks_page_2, meta={'returns_page1': returns_page1})
def stocks_page_2(self, response):
# Grab data again...
Now, instead of writing 19 or more functions, I was wondering if there was a way I could loop through an iteration using one function to grab all data from all pages available for a given stock.
Something like this:
for x in range(30): # 30 was randomly selected
current_page = response.url
# Grabs Data
# Check if there is a 'next' page:
if response.xpath('//td[#align="right"]/a[#rel="next"]').extract() != ' ':
u = x * 66
next_page = current_page + "&z=66&y={0}".format(u)
# Go to the next page somehow within the function???
Updated Code:
Works, but only returns one page of data.
class DmozSpider(CrawlSpider):
name = "dnot"
allowed_domains = ["finance.yahoo.com", "http://eoddata.com/"]
start_urls = ['http://finance.yahoo.com/q?s=CAT']
rules = [
Rule(LinkExtractor(restrict_xpaths='//td[#align="right"]/a[#rel="next"]'),
callback='stocks1',
follow=True),
]
def stocks1(self, response):
returns = []
rows = response.xpath('//table[#class="yfnc_datamodoutline1"]//table/tr')[1:]
for row in rows:
cells = row.xpath('.//td/text()').extract()
try:
values = cells[-1]
try:
float(values)
returns.append(values)
except ValueError:
continue
except ValueError:
continue
unformatted_returns = response.meta.get('returns_pages')
returns = [float(i) for i in returns]
global required_amount_of_returns, counter
if counter == 1 and "CAT" in response.url:
required_amount_of_returns = len(returns)
elif required_amount_of_returns == 0:
raise CloseSpider("'Error with initiating required amount of returns'")
counter += 1
print counter
# Iterator to calculate Rate of return
# ====================================
if data_intervals == "m":
k = 12
elif data_intervals == "w":
k = 4
else:
k = 30
sub_returns_amount = required_amount_of_returns - k
sub_returns = returns[:sub_returns_amount]
rate_of_return = []
if len(returns) == required_amount_of_returns or "CAT" in response.url:
for number in sub_returns:
numerator = number - returns[k]
rate = numerator/returns[k]
if rate == '':
rate = 0
rate_of_return.append(rate)
k += 1
item = Website()
items = []
item['url'] = response.url
item['name'] = response.xpath('//div[#class="title"]/h2/text()').extract()
item['avg_returns'] = numpy.average(rate_of_return)
item['var_returns'] = numpy.cov(rate_of_return)
item['sd_returns'] = numpy.std(rate_of_return)
item['returns'] = returns
item['rate_of_returns'] = rate_of_return
item['exchange'] = response.xpath('//span[#class="rtq_exch"]/text()').extract()
item['ind_sharpe'] = ((numpy.average(rate_of_return) - RFR) / numpy.std(rate_of_return))
items.append(item)
yield item

You see, a parse callback is just a function that takes the response and returns or yields either Items or Requests or both. There is no issue at all with reusing these callbacks, so you can just pass the same callback for every request.
Now, you could pass the current page info using the Request meta but instead, I'd leverage the CrawlSpider to crawl across every page. It's really easy, start generating the Spider with the command line:
scrapy genspider --template crawl finance finance.yahoo.com
Then write it like this:
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule
Scrapy 1.0 has deprecated the scrapy.contrib namespace for the modules above, but if you're stuck with 0.24, use scrapy.contrib.linkextractors and scrapy.contrib.spiders.
from yfinance.items import YfinanceItem
class FinanceSpider(CrawlSpider):
name = 'finance'
allowed_domains = ['finance.yahoo.com']
start_urls = ['http://finance.yahoo.com/q/hp?s=PWF.TO&a=04&b=19&c=2005&d=04&e=19&f=2010&g=d&z=66&y=132']
rules = (
Rule(LinkExtractor(restrict_css='[rel="next"]'),
callback='parse_items',
follow=True),
)
LinkExtractor will pick up the links in the response to follow, but it can be limited with XPath (or CSS) and regular expressions. See documentation for more.
Rules will follow the links and call the callback on every response. follow=True will keep extracting links on every new response, but it can be limited by depth. See documentation again.
def parse_items(self, response):
for line in response.css('.yfnc_datamodoutline1 table tr')[1:-1]:
yield YfinanceItem(date=line.css('td:first-child::text').extract()[0])
Just yield the Items, since Requests for the next pages will be handled by the CrawlSpider Rules.

Scrapy: Wait for a specific url to be parsed before parsing others

Brief Explanation:
I have a Scrapy project that takes stock data from Yahoo! Finance. In order for my project to work, I need to ensure that a stock has been around for a desired amount of time. I do this by scraping CAT (Caterpillar Inc. (CAT) -NYSE) first, get the amount of closing prices that there is for that time period, and then ensure that all stocks scraped after that have the same amount of closing prices as CAT, thus ensuring that a stock has been publicly traded for the desired time length.
The Problem:
This all works fine and dandy, however my problem is that before scrapy has finished parsing CAT, it begins scraping other stocks and parsing them. This results in an error, as before I can get the desired amount of closing prices from CAT, scrapy is trying to decide if any other stock has the same amount of closing prices as CAT, which does not exist yet.
The actual question
How can I force scrapy to finish parsing one url before beginning others
I have also tried:
def start_requests(self):
global start_time
yield Request('http://finance.yahoo.com/q?s=CAT', self.parse)
# Waits 4 seconds to allow CAT to finish crawling
if time.time() - start_time > 0.2:
for i in self.other_urls:
yield Request(i, self.parse)
but the stocks in other_urls never commence, because scrapy never goes back to def start_requests to check if the time is above 0.2
The Entire Code:
from scrapy.selector import Selector
from scrapy import Request
from scrapy.exceptions import CloseSpider
from sharpeparser.gen_settings import *
from decimal import Decimal
from scrapy.spider import Spider
from sharpeparser.items import SharpeparserItem
import numpy
import time
if data_intervals == "m":
required_amount_of_returns = 24
elif data_intervals == "w":
required_amount_of_returns = 100
else:
required_amount_of_returns =
counter = 1
start_time = time.time()
class DnotSpider(Spider):
# ---- >>> ENSURE YOU INDENT 1 ---- >>>
# =======================================
name = "dnot"
allowed_domains = ["finance.yahoo.com", "http://eoddata.com/", "ca.finance.yahoo.com"]
start_urls = ['http://finance.yahoo.com/q?s=CAT']
other_urls = ['http://eoddata.com/stocklist/TSX.htm', 'http://eoddata.com/stocklist/TSX/B.htm', 'http://eoddata.com/stocklist/TSX/C.htm', 'http://eoddata.com/stocklist/TSX/D.htm', 'http://eoddata.com/stocklist/TSX/E.htm', 'http://eoddata.com/stocklist/TSX/F.htm', 'http://eoddata.com/stocklist/TSX/G.htm', 'http://eoddata.com/stocklist/TSX/H.htm', 'http://eoddata.com/stocklist/TSX/I.htm', 'http://eoddata.com/stocklist/TSX/J.htm', 'http://eoddata.com/stocklist/TSX/K.htm', 'http://eoddata.com/stocklist/TSX/L.htm', 'http://eoddata.com/stocklist/TSX/M.htm', 'http://eoddata.com/stocklist/TSX/N.htm', 'http://eoddata.com/stocklist/TSX/O.htm', 'http://eoddata.com/stocklist/TSX/P.htm', 'http://eoddata.com/stocklist/TSX/Q.htm', 'http://eoddata.com/stocklist/TSX/R.htm', 'http://eoddata.com/stocklist/TSX/S.htm', 'http://eoddata.com/stocklist/TSX/T.htm', 'http://eoddata.com/stocklist/TSX/U.htm', 'http://eoddata.com/stocklist/TSX/V.htm', 'http://eoddata.com/stocklist/TSX/W.htm', 'http://eoddata.com/stocklist/TSX/X.htm', 'http://eoddata.com/stocklist/TSX/Y.htm', 'http://eoddata.com/stocklist/TSX/Z.htm'
'http://eoddata.com/stocklist/NASDAQ/B.htm', 'http://eoddata.com/stocklist/NASDAQ/C.htm', 'http://eoddata.com/stocklist/NASDAQ/D.htm', 'http://eoddata.com/stocklist/NASDAQ/E.htm', 'http://eoddata.com/stocklist/NASDAQ/F.htm', 'http://eoddata.com/stocklist/NASDAQ/G.htm', 'http://eoddata.com/stocklist/NASDAQ/H.htm', 'http://eoddata.com/stocklist/NASDAQ/I.htm', 'http://eoddata.com/stocklist/NASDAQ/J.htm', 'http://eoddata.com/stocklist/NASDAQ/K.htm', 'http://eoddata.com/stocklist/NASDAQ/L.htm', 'http://eoddata.com/stocklist/NASDAQ/M.htm', 'http://eoddata.com/stocklist/NASDAQ/N.htm', 'http://eoddata.com/stocklist/NASDAQ/O.htm', 'http://eoddata.com/stocklist/NASDAQ/P.htm', 'http://eoddata.com/stocklist/NASDAQ/Q.htm', 'http://eoddata.com/stocklist/NASDAQ/R.htm', 'http://eoddata.com/stocklist/NASDAQ/S.htm', 'http://eoddata.com/stocklist/NASDAQ/T.htm', 'http://eoddata.com/stocklist/NASDAQ/U.htm', 'http://eoddata.com/stocklist/NASDAQ/V.htm', 'http://eoddata.com/stocklist/NASDAQ/W.htm', 'http://eoddata.com/stocklist/NASDAQ/X.htm', 'http://eoddata.com/stocklist/NASDAQ/Y.htm', 'http://eoddata.com/stocklist/NASDAQ/Z.htm',
'http://eoddata.com/stocklist/NYSE/B.htm', 'http://eoddata.com/stocklist/NYSE/C.htm', 'http://eoddata.com/stocklist/NYSE/D.htm', 'http://eoddata.com/stocklist/NYSE/E.htm', 'http://eoddata.com/stocklist/NYSE/F.htm', 'http://eoddata.com/stocklist/NYSE/G.htm', 'http://eoddata.com/stocklist/NYSE/H.htm', 'http://eoddata.com/stocklist/NYSE/I.htm', 'http://eoddata.com/stocklist/NYSE/J.htm', 'http://eoddata.com/stocklist/NYSE/K.htm', 'http://eoddata.com/stocklist/NYSE/L.htm', 'http://eoddata.com/stocklist/NYSE/M.htm', 'http://eoddata.com/stocklist/NYSE/N.htm', 'http://eoddata.com/stocklist/NYSE/O.htm', 'http://eoddata.com/stocklist/NYSE/P.htm', 'http://eoddata.com/stocklist/NYSE/Q.htm', 'http://eoddata.com/stocklist/NYSE/R.htm', 'http://eoddata.com/stocklist/NYSE/S.htm', 'http://eoddata.com/stocklist/NYSE/T.htm', 'http://eoddata.com/stocklist/NYSE/U.htm', 'http://eoddata.com/stocklist/NYSE/V.htm', 'http://eoddata.com/stocklist/NYSE/W.htm', 'http://eoddata.com/stocklist/NYSE/X.htm', 'http://eoddata.com/stocklist/NYSE/Y.htm', 'http://eoddata.com/stocklist/NYSE/Z.htm',
'http://eoddata.com/stocklist/HKEX/0.htm', 'http://eoddata.com/stocklist/HKEX/1.htm', 'http://eoddata.com/stocklist/HKEX/2.htm', 'http://eoddata.com/stocklist/HKEX/3.htm', 'http://eoddata.com/stocklist/HKEX/6.htm', 'http://eoddata.com/stocklist/HKEX/8.htm',
'http://eoddata.com/stocklist/LSE/0.htm', 'http://eoddata.com/stocklist/LSE/1.htm', 'http://eoddata.com/stocklist/LSE/2.htm', 'http://eoddata.com/stocklist/LSE/3.htm', 'http://eoddata.com/stocklist/LSE/4.htm', 'http://eoddata.com/stocklist/LSE/5.htm', 'http://eoddata.com/stocklist/LSE/6.htm', 'http://eoddata.com/stocklist/LSE/7.htm', 'http://eoddata.com/stocklist/LSE/8.htm', 'http://eoddata.com/stocklist/LSE/9.htm', 'http://eoddata.com/stocklist/LSE/A.htm', 'http://eoddata.com/stocklist/LSE/B.htm', 'http://eoddata.com/stocklist/LSE/C.htm', 'http://eoddata.com/stocklist/LSE/D.htm', 'http://eoddata.com/stocklist/LSE/E.htm', 'http://eoddata.com/stocklist/LSE/F.htm', 'http://eoddata.com/stocklist/LSE/G.htm', 'http://eoddata.com/stocklist/LSE/H.htm', 'http://eoddata.com/stocklist/LSE/I.htm', 'http://eoddata.com/stocklist/LSE/G.htm', 'http://eoddata.com/stocklist/LSE/K.htm', 'http://eoddata.com/stocklist/LSE/L.htm', 'http://eoddata.com/stocklist/LSE/M.htm', 'http://eoddata.com/stocklist/LSE/N.htm', 'http://eoddata.com/stocklist/LSE/O.htm', 'http://eoddata.com/stocklist/LSE/P.htm', 'http://eoddata.com/stocklist/LSE/Q.htm', 'http://eoddata.com/stocklist/LSE/R.htm', 'http://eoddata.com/stocklist/LSE/S.htm', 'http://eoddata.com/stocklist/LSE/T.htm', 'http://eoddata.com/stocklist/LSE/U.htm', 'http://eoddata.com/stocklist/LSE/V.htm', 'http://eoddata.com/stocklist/LSE/W.htm', 'http://eoddata.com/stocklist/LSE/X.htm', 'http://eoddata.com/stocklist/LSE/Y.htm', 'http://eoddata.com/stocklist/LSE/Z.htm',
'http://eoddata.com/stocklist/AMS/A.htm', 'http://eoddata.com/stocklist/AMS/B.htm', 'http://eoddata.com/stocklist/AMS/C.htm', 'http://eoddata.com/stocklist/AMS/D.htm', 'http://eoddata.com/stocklist/AMS/E.htm', 'http://eoddata.com/stocklist/AMS/F.htm', 'http://eoddata.com/stocklist/AMS/G.htm', 'http://eoddata.com/stocklist/AMS/H.htm', 'http://eoddata.com/stocklist/AMS/I.htm', 'http://eoddata.com/stocklist/AMS/J.htm', 'http://eoddata.com/stocklist/AMS/K.htm', 'http://eoddata.com/stocklist/AMS/L.htm', 'http://eoddata.com/stocklist/AMS/M.htm', 'http://eoddata.com/stocklist/AMS/N.htm', 'http://eoddata.com/stocklist/AMS/O.htm', 'http://eoddata.com/stocklist/AMS/P.htm', 'http://eoddata.com/stocklist/AMS/Q.htm', 'http://eoddata.com/stocklist/AMS/R.htm', 'http://eoddata.com/stocklist/AMS/S.htm', 'http://eoddata.com/stocklist/AMS/T.htm', 'http://eoddata.com/stocklist/AMS/U.htm', 'http://eoddata.com/stocklist/AMS/V.htm', 'http://eoddata.com/stocklist/AMS/W.htm', 'http://eoddata.com/stocklist/AMS/X.htm', 'http://eoddata.com/stocklist/AMS/Y.htm', 'http://eoddata.com/stocklist/AMS/Z.htm',
'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=A', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=B', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=C', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=D', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=E', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=F', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=G', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=H', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=I', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=J', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=K', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=L', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=M', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=N', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=O', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=P', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=Q', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=R', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=S', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=T', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=U', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=V', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=W', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=X', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=Y', 'https://ca.finance.yahoo.com/q/cp?s=%5EIXIC&alpha=Z',
'https://ca.finance.yahoo.com/q/cp?s=%5EHSI&alpha=0', 'https://ca.finance.yahoo.com/q/cp?s=%5EHSI&alpha=1', 'https://ca.finance.yahoo.com/q/cp?s=%5EHSI&alpha=2', 'https://ca.finance.yahoo.com/q/cp?s=%5EHSI&alpha=3',
'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=A', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=B', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=C', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=D', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=E', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=F', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=G', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=H', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=I', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=J', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=K', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=L', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=M', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=N', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=O', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=P', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=Q', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=R', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=S', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=T', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=U', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=V', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=W', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=X', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=Y', 'http://finance.yahoo.com/q/cp?s=%5EN100&alpha=Z',
'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=A', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=B', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=C', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=D', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=E', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=F', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=G', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=H', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=I', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=J', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=K', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=L', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=M', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=N', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=O', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=P', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=Q', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=R', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=S', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=T', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=U', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=V', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=W', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=X', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=Y', 'http://finance.yahoo.com/q/cp?s=%5EFCHI&alpha=Z',
'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=A', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=B', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=C', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=D', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=E', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=F', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=G', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=H', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=I', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=J', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=K', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=L', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=M', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=N', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=O', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=P', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=Q', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=R', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=S', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=T', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=U', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=V', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=W', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=X', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=Y', 'http://finance.yahoo.com/q/cp?s=%5EAEX&alpha=Z']
def start_requests(self):
global start_time
yield Request('http://finance.yahoo.com/q?s=CAT', self.parse)
# Waits 4 seconds to allow CAT to finish crawling
if time.time() - start_time > 0.2:
for i in self.other_urls:
yield Request(i, self.parse)
def parse(self, response):
if "eoddata" in response.url:
companyList = response.xpath('//tr[#class="ro"]/td/a/text()').extract()
for company in companyList:
if "TSX" in response.url:
go = 'http://finance.yahoo.com/q/hp?s={0}.TO&a={1}&b={2}&c={3}&d={4}&e={5}&f={6}&g={7}'.format(company, beginning_month, beginning_day, beginning_year, ending_month, ending_day, ending_year, data_intervals)
yield Request(go, self.stocks1)
elif "LSE" in response.url:
go = 'http://finance.yahoo.com/q/hp?s={0}.L&a={1}&b={2}&c={3}&d={4}&e={5}&f={6}&g={7}'.format(company, beginning_month, beginning_day, beginning_year, ending_month, ending_day, ending_year, data_intervals)
yield Request(go, self.stocks1)
elif "HKEX" in response.url:
go = 'http://finance.yahoo.com/q/hp?s={0}.HK&a={1}&b={2}&c={3}&d={4}&e={5}&f={6}&g={7}'.format(company, beginning_month, beginning_day, beginning_year, ending_month, ending_day, ending_year, data_intervals)
yield Request(go, self.stocks1)
elif "AMS" in response.url:
go = 'https://ca.finance.yahoo.com/q/hp?s={0}.AS&a={1}&b={2}&c={3}&d={4}&e={5}&f={6}&g={7}'.format(company, beginning_month, beginning_day, beginning_year, ending_month, ending_day, ending_year, data_intervals)
yield Request(go, self.stocks1)
else:
go = 'https://ca.finance.yahoo.com/q/hp?s={0}&a={1}&b={2}&c={3}&d={4}&e={5}&f={6}&g={7}'.format(company, beginning_month, beginning_day, beginning_year, ending_month, ending_day, ending_year, data_intervals)
yield Request(go, self.stocks1)
elif "http://finance.yahoo.com/q?s=CAT" in response.url:
go = 'http://finance.yahoo.com/q/hp?s=CAT&a={0}&b={1}&c={2}&d={3}&e={4}&f={5}&g={6}'.format(beginning_month, beginning_day, beginning_year, ending_month, ending_day, ending_year, data_intervals)
yield Request(go, self.stocks1)
else:
rows = response.xpath('//table[#class="yfnc_tableout1"]//table/tr')[1:]
for row in rows:
company = row.xpath('.//td[1]/b/a/text()').extract()
go = 'http://finance.yahoo.com/q/hp?s={0}&a={1}&b={2}&c={3}&d={4}&e={5}&f={6}&g={7}'.format(company, beginning_day, beginning_month, beginning_year, ending_day, ending_month, ending_year, data_intervals)
yield Request(go, self.stocks1)
def stocks1(self, response):
current_page = response.url
print current_page
# If the link is not the same as the first page, ie. stocks1 is requested through stocks2, get the stock data from stocks2
if initial_ending not in current_page[-iel:]:
returns_pages = response.meta.get('returns_pages')
# Remove the last stock price from the stock list, because it is the same as the first on the new list
if not not returns_pages:
if len(returns_pages) > 2:
returns_pages = returns_pages[:-1]
else:
# Else, if the link does match that of the first page, create a new list becuase one does not exist yet
returns_pages = []
# This grabs the stock data from the page
rows = response.xpath('//table[#class="yfnc_datamodoutline1"]//table/tr')[1:]
print "stocks1"
print returns_pages
for row in rows:
cells = row.xpath('.//td/text()').extract()
try:
values = cells[-1]
try:
float(values)
# And adds it to returns_pages
returns_pages.append(values)
except ValueError:
continue
except ValueError:
continue
print "after"
print returns_pages
# exp determines if there is a 'Next page' or not
exp = response.xpath('//td[#align="right"]/a[#rel="next"]').extract()
# If there is a 'Next Page':
if not not exp:
# And this is the first page:
if initial_ending in current_page[-iel:]:
#create necessary url for the 2nd page
next_page = current_page + "&z=66&y=66"
# If this is not the first page
else:
# This increases the end of the link by 66, thereby getting the next 66 results on for pages 2 and after
u = int(current_page[-6:].split("=",1)[1])
o = len(str(u))
u += 66
next_page = current_page[:-o] + str(u)
print next_page, "66&y in curr_page"
# Then go back to self.stocks1 to get more data on the next page
yield Request(next_page, self.stocks2, meta={'returns_pages': returns_pages}, dont_filter=True)
# Else, if there is no 'Next Link'
else:
# Send the retuns to finalize.stock to be saved in the item
yield Request(current_page, callback=self.finalize_stock, meta={'returns_pages': returns_pages}, dont_filter=True)
def stocks2(self, response):
# Prints the link of the current url
current_page = response.url
print current_page
# Gets the returns from the previous page
returns_pages = response.meta.get('returns_pages')
# Removes the last return from the previous page because it will be a duplicate
returns_pages = returns_pages[:-1]
print "stocks2"
print returns_pages
# Gets all of the returns on the page
rows = response.xpath('//table[#class="yfnc_datamodoutline1"]//table/tr')[1:]
for row in rows:
cells = row.xpath('.//td/text()').extract()
try:
values = cells[-1]
try:
float(values)
# And adds it to the previous returns
returns_pages.append(values)
except ValueError:
continue
except ValueError:
continue
print "after 2"
print returns_pages
# exp determines if there is a 'Next page' or not
exp = response.xpath('//td[#align="right"]/a[#rel="next"]').extract()
# If there is a 'Next Page':
if not not exp:
# And somehow, this is the first page (should never be true)
if initial_ending in current_page[-iel:]:
# Add necessary link to go to the second page
next_page = current_page + "&z=66&y=66"
print next_page, "66&y not in curr_page"
# Else, this is not the first page (should always be true)
else:
# add 66 to the last number on the preceeding link in order to access the second or later pages
u = int(current_page[-6:].split("=",1)[1])
o = len(str(u))
u += 66
next_page = current_page[:-o] + str(u)
print next_page, "66&y in curr_page"
# go back to self.stocks1 to get more data on the next page
yield Request(next_page, self.stocks1, meta={'returns_pages': returns_pages}, dont_filter=True)
else:
# If there is no "Next" link, send the retuns to finalize.stock to be saved in the item
yield Request(current_page, callback=self.finalize_stock, meta={'returns_pages': returns_pages}, dont_filter=True)
print "sending to finalize stock"
def finalize_stock(self,response):
current_page = response.url
print "====================="
print "finalize_stock called"
print current_page
print "====================="
unformatted_returns = response.meta.get('returns_pages')
returns = [float(i) for i in unformatted_returns]
global required_amount_of_returns, counter
if counter == 1 and "CAT" in response.url:
required_amount_of_returns = len(returns)
elif required_amount_of_returns == 0:
raise CloseSpider("'Error with initiating required amount of returns'")
counter += 1
print counter
# Iterator to calculate Rate of return
# ====================================
if data_intervals == "m":
k = 12
elif data_intervals == "w":
k = 4
else:
k = 30
sub_returns_amount = required_amount_of_returns - k
sub_returns = returns[:sub_returns_amount]
rate_of_return = []
RFR = 0.03
# Make sure list is exact length, otherwise rate_of_return will be inaccurate
# Returns has not been checked by pipeline yet, so small lists will be in the variable
if len(returns) > required_amount_of_returns:
for number in sub_returns:
numerator = number - returns[k]
rate = numerator/returns[k]
if rate == '':
rate = 0
rate_of_return.append(rate)
k += 1
item = SharpeparserItem()
items = []
item['url'] = response.url
item['name'] = response.xpath('//div[#class="title"]/h2/text()').extract()
item['avg_returns'] = numpy.average(rate_of_return)
item['var_returns'] = numpy.cov(rate_of_return)
item['sd_returns'] = numpy.std(rate_of_return)
item['returns'] = unformatted_returns
item['rate_of_returns'] = rate_of_return
item['exchange'] = response.xpath('//span[#class="rtq_exch"]/text()').extract()
item['ind_sharpe'] = ((numpy.average(rate_of_return) - RFR) / numpy.std(rate_of_return))
items.append(item)
yield item

Actual Question
As for the actual problem of doing each request in sequence... There are a few questions similar to yours:
crawling sites one-by-one
crawling urls in order
processing urls sequentially
As a general summary there seem to be a couple of options:
Utilise the priority flag in a start_requests() function to iterate through websites in a particular order
Set CONCURRENT_REQUESTS=1 to ensure that only one request is carried out at a time
If you want to parse all sites all at once after the first CAT ticker has been done. It might be possible to specify an if function to flick the above setting to a higher value if you have already parsed the first site using the settings API
General Coding
I can't run your exact code because you are missing the class structure but I can already see a few things that might be tripping you up:
This SO post describes yield. to better understand how your yield function is working run the following:
def it():
yield range(2)
yield range(10)
g = it()
for i in g:
print i
# now the generator has been consumed.
for i in g:
print i
This SO post also demonstrates that the start_requests() function overrides the list specified by start_urls. It appears that for this reason your urls in start_urls are overridden by this function which only ever yields a generator expression of Request('http://finance.yahoo.com/q?s=CAT', self.parse)
Is there any particular reason that you are not listing all the urls in the list start_urls in the order you want them parsed and delete the function start_requests()? The docs on start_urls state:
subsequent URLs will be generated successively from data contained in the start URLs
Sticking things in globals will tend to cause you problems in projects like this, it's usually better to initiate them as attributes of self in a def __init__(self): function which will be called when the class is called.
This might be petty but you could save yourself a lot of scrolling / effort by listing all the symbols in a separate file and then just load them up in your code. As it stands you have a lot of repetition in that list that you could cut out and make it far easier to read.