Reputation: 61
How can I scrape multiple URLs with Scrapy?
Am I forced to make multiple crawlers?
class TravelSpider(BaseSpider):
name = "speedy"
allowed_domains = ["example.com"]
start_urls = ["http://example.com/category/top/page-%d/" % i for i in xrange(4),"http://example.com/superurl/top/page-%d/" % i for i in xrange(55)]
def parse(self, response):
hxs = HtmlXPathSelector(response)
items = []
item = TravelItem()
item['url'] = hxs.select('//a[@class="out"]/@href').extract()
out = "\n".join(str(e) for e in item['url']);
print out
Python says:
NameError: name 'i' is not defined
But when I use one URL it works fine!
start_urls = ["http://example.com/category/top/page-%d/" % i for i in xrange(4)"]
Upvotes: 2
Views: 5889
Reputation: 41
There are only four ranges in Python: LEGB
, because the local scope of the class
definition and the local extent of the list derivation
are not nested functions, so they do not form the Enclosing scope.Therefore, they are two separate local scopes that cannot be accessed from each other.
so, don't use 'for' and class variables at the same time
Upvotes: 0
Reputation: 2254
Your python syntax is incorrect, try:
start_urls = ["http://example.com/category/top/page-%d/" % i for i in xrange(4)] + \
["http://example.com/superurl/top/page-%d/" % i for i in xrange(55)]
If you need to write code to generate start requests, you can define a start_requests() method instead of using start_urls.
Upvotes: 3
Reputation: 473763
You can initialize start_urls
in __init__.py
method:
from scrapy.item import Item, Field
from scrapy.selector import HtmlXPathSelector
from scrapy.spider import BaseSpider
class TravelItem(Item):
url = Field()
class TravelSpider(BaseSpider):
def __init__(self, name=None, **kwargs):
self.start_urls = []
self.start_urls.extend(["http://example.com/category/top/page-%d/" % i for i in xrange(4)])
self.start_urls.extend(["http://example.com/superurl/top/page-%d/" % i for i in xrange(55)])
super(TravelSpider, self).__init__(name, **kwargs)
name = "speedy"
allowed_domains = ["example.com"]
def parse(self, response):
hxs = HtmlXPathSelector(response)
items = []
item = TravelItem()
item['url'] = hxs.select('//a[@class="out"]/@href').extract()
out = "\n".join(str(e) for e in item['url']);
print out
Hope that helps.
Upvotes: 3