How to stop scrapy spider after certain number of requests?

Question

I am developing an simple scraper to get 9 gag posts and its images but due to some technical difficulties iam unable to stop the scraper and it keeps on scraping which i dont want.I want to increase the counter value and stop after 100 posts. But the 9gag page was designed in a fashion in each response it gives only 10 posts and after each iteration my counter value resets to 10 in this case my loop runs infintely long and never stops.

---

# -*- coding: utf-8 -*-
import scrapy
from _9gag.items import GagItem

class FirstSpider(scrapy.Spider):
    name = "first"
    allowed_domains = ["9gag.com"]
    start_urls = (
        'http://www.9gag.com/',
    )

    last_gag_id = None
    def parse(self, response):
        count = 0
        for article in response.xpath('//article'):
            gag_id = article.xpath('@data-entry-id').extract()
            count +=1
            if gag_id:
                if (count != 100):
                    last_gag_id = gag_id[0]
                    ninegag_item = GagItem()
                    ninegag_item['entry_id'] = gag_id[0]
                    ninegag_item['url'] = article.xpath('@data-entry-url').extract()[0]
                    ninegag_item['votes'] = article.xpath('@data-entry-votes').extract()[0]
                    ninegag_item['comments'] = article.xpath('@data-entry-comments').extract()[0]
                    ninegag_item['title'] = article.xpath('.//h2/a/text()').extract()[0].strip()
                    ninegag_item['img_url'] = article.xpath('.//div[1]/a/img/@src').extract()

                    yield ninegag_item


                else:
                    break


        next_url = 'http://9gag.com/?id=%s&c=200' % last_gag_id
        yield scrapy.Request(url=next_url, callback=self.parse) 
        print count

Code for items.py is here

from scrapy.item import Item, Field


class GagItem(Item):
    entry_id = Field()
    url = Field()
    votes = Field()
    comments = Field()
    title = Field()
    img_url = Field()

So i want to increase a global count value and tried this by passing 3 arguments to parse function it gives error

TypeError: parse() takes exactly 3 arguments (2 given)

So is there a way to pass a global count value and return it after each iteration and stop after 100 posts(suppose).

Entire project is available here Github Even if i set POST_LIMIT =100 the infinite loop happens,see here command i executed

scrapy crawl first -s POST_LIMIT=10 --output=output.json

Answer 1

There's a built-in setting CLOSESPIDER_PAGECOUNT that can be passed via command-line -s argument or changed in settings: scrapy crawl <spider> -s CLOSESPIDER_PAGECOUNT=100

One small caveat is that if you've enabled caching, it will count cache hits as page counts as well.

Answer 2

First: Use self.count and initialize outside of parse. Then don't prevent the parsing of the items, but generating new requests. See the following code:

# -*- coding: utf-8 -*-
import scrapy
from scrapy import Item, Field


class GagItem(Item):
    entry_id = Field()
    url = Field()
    votes = Field()
    comments = Field()
    title = Field()
    img_url = Field()


class FirstSpider(scrapy.Spider):

    name = "first"
    allowed_domains = ["9gag.com"]
    start_urls = ('http://www.9gag.com/', )

    last_gag_id = None
    COUNT_MAX = 30
    count = 0

    def parse(self, response):

        for article in response.xpath('//article'):
            gag_id = article.xpath('@data-entry-id').extract()
            ninegag_item = GagItem()
            ninegag_item['entry_id'] = gag_id[0]
            ninegag_item['url'] = article.xpath('@data-entry-url').extract()[0]
            ninegag_item['votes'] = article.xpath('@data-entry-votes').extract()[0]
            ninegag_item['comments'] = article.xpath('@data-entry-comments').extract()[0]
            ninegag_item['title'] = article.xpath('.//h2/a/text()').extract()[0].strip()
            ninegag_item['img_url'] = article.xpath('.//div[1]/a/img/@src').extract()
            self.last_gag_id = gag_id[0]
            self.count = self.count + 1
            yield ninegag_item

        if (self.count < self.COUNT_MAX):
            next_url = 'http://9gag.com/?id=%s&c=10' % self.last_gag_id
            yield scrapy.Request(url=next_url, callback=self.parse)