How to control the order of yield in Scrapy

How to control the order of yield in Scrapy

By : John Gatti
Date : November 22 2020, 09:00 AM
With these it helps you need to yield the item on the final callback, parse isn't stopping for parse_member to finish, so the group_item in parse isn't changing while parse_member is working.
Don't yield the group_item of parse, just the one on parse_member, as you already copied the previous item on meta and you already recovered it on parse_member with response.meta['group_item']
code :

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yield multiple request to a same parse function. what is the order of function running? Scrapy

yield multiple request to a same parse function. what is the order of function running? Scrapy

By : ccharron
Date : March 29 2020, 07:55 AM
will be helpful for those in need You are reusing the same webdriver instance in the second_parse() method. I suspect this is what causing problems since the already instantiated webdriver navigates to a different page when not done with the current. You should instantiate and then close a webdriver in the second_parse() method:
code :
def second_parse(self, response):
   webDriver = webdriver.Firefox()

   # scrape

How to yield several requests in order in Scrapy?

How to yield several requests in order in Scrapy?

By : user2077190
Date : March 29 2020, 07:55 AM
Hope that helps Use a return statement instead of yield.
You don't even need to touch any setting:
code :
from scrapy.spiders import Spider, Request

class MySpider(Spider):

    name = 'toscrape.com'
    start_urls = ['http://books.toscrape.com/catalogue/page-1.html']

    urls = (
        'http://books.toscrape.com/catalogue/page-{}.html'.format(i + 1) for i in range(50)

    def parse(self, response):
        for url in self.urls:
            return Request(url)
2018-11-20 03:35:43 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-1.html> (referer: http://books.toscrape.com/catalogue/page-1.html)
2018-11-20 03:35:43 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-2.html> (referer: http://books.toscrape.com/catalogue/page-1.html)
2018-11-20 03:35:44 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-3.html> (referer: http://books.toscrape.com/catalogue/page-2.html)
2018-11-20 03:35:44 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-4.html> (referer: http://books.toscrape.com/catalogue/page-3.html)
2018-11-20 03:35:45 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-5.html> (referer: http://books.toscrape.com/catalogue/page-4.html)
2018-11-20 03:35:45 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-6.html> (referer: http://books.toscrape.com/catalogue/page-5.html)
2018-11-20 03:35:45 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-7.html> (referer: http://books.toscrape.com/catalogue/page-6.html)
2018-11-20 03:35:46 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-8.html> (referer: http://books.toscrape.com/catalogue/page-7.html)
2018-11-20 03:35:46 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-9.html> (referer: http://books.toscrape.com/catalogue/page-8.html)
2018-11-20 03:35:47 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-10.html> (referer: http://books.toscrape.com/catalogue/page-9.html)
2018-11-20 03:35:47 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-11.html> (referer: http://books.toscrape.com/catalogue/page-10.html)
2018-11-20 03:35:47 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-12.html> (referer: http://books.toscrape.com/catalogue/page-11.html)
2018-11-20 03:35:48 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-13.html> (referer: http://books.toscrape.com/catalogue/page-12.html)
2018-11-20 03:35:48 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-14.html> (referer: http://books.toscrape.com/catalogue/page-13.html)
2018-11-20 03:35:49 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-15.html> (referer: http://books.toscrape.com/catalogue/page-14.html)
2018-11-20 03:35:49 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-16.html> (referer: http://books.toscrape.com/catalogue/page-15.html)
2018-11-20 03:35:50 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-17.html> (referer: http://books.toscrape.com/catalogue/page-16.html)
2018-11-20 03:35:50 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-18.html> (referer: http://books.toscrape.com/catalogue/page-17.html)
2018-11-20 03:35:50 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-19.html> (referer: http://books.toscrape.com/catalogue/page-18.html)
2018-11-20 03:35:51 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-20.html> (referer: http://books.toscrape.com/catalogue/page-19.html)
2018-11-20 03:35:51 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-21.html> (referer: http://books.toscrape.com/catalogue/page-20.html)
2018-11-20 03:35:52 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-22.html> (referer: http://books.toscrape.com/catalogue/page-21.html)
2018-11-20 03:35:52 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-23.html> (referer: http://books.toscrape.com/catalogue/page-22.html)
2018-11-20 03:35:53 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-24.html> (referer: http://books.toscrape.com/catalogue/page-23.html)
2018-11-20 03:35:53 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://books.toscrape.com/catalogue/page-25.html> (referer: http://books.toscrape.com/catalogue/page-24.html)
Yield or return for Scrapy?

Yield or return for Scrapy?

By : Fbrufino
Date : March 29 2020, 07:55 AM
wish of those help Yield will return a generator. The return will only return the first v in values and the rest of the loop is skipped. Basically if you use yield, you will get back a generator with all the values in lowercase. If you use a return it will just return the first value in lowercase.
Python Scrapy & Yield

Python Scrapy & Yield

By : James Farr
Date : March 29 2020, 07:55 AM
I wish this helpful for you Normally when obtaining data, you'll have to use Scrapy Items but they can also be replaced with dictionaries (which would be the JSON objects you are referring to), so we'll use them now:
First, start creating the item (or dictionary) in the parse_individual_listings method, just as you did with data in parse_individual_tabs. Then pass it to the next request (that will be caught by parse_individual_tabs with the meta argument, so it should look like:
How to use the `yield Request()` to control the FOR Loop in scrapy?

How to use the `yield Request()` to control the FOR Loop in scrapy?

By : Brushanen
Date : September 29 2020, 07:00 AM
should help you out You could request the next page after parsing the current one. Thus, you could decide to continue if the list is not empty. Eg.
code :
start_urls = ['http://example.com/?p=1']
base_url = 'http://example.com/?p={}'

def parse(self, response):   

    # ... do what you want to do with the list, then ...

    if title_list:
        next_page = response.meta.get('page', 1) + 1
        yield Request(
            meta={'page': next_page},  
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