将 Scrapy Crawler Rule 中的相对 URL 转换为绝对 URL

Question

我正在尝试使用此规则创建一个爬虫，它将点击进入每个属性的页面并获取详细信息。但是 URL 是一个相对 URL，不能在 Scrapy Crawler Rule 中使用，因为它只接受绝对 URL。这是我使用 process_value 提出的解决方案，但它不起作用。谁能帮忙推荐另一种方法来解决这个问题，谢谢！

这是目前的代码：

import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule


class EdgepropSpider(CrawlSpider):
    name = 'edgeprop'
    allowed_domains = ['edgeprop.my']
    start_urls = ['https://www.edgeprop.my/buy/malaysia/all-residential']

    rules = (
        Rule(LinkExtractor(restrict_xpaths=("//div[@class='card tep-listing-card']/a/@href"), process_value= lambda x: 'https://edgeprop.my'+x), callback='parse_item', follow=True),
        #Rule(LinkExtractor(restrict_xpaths=("//nav[@aria-label='Listing Page navigation']//li[position() = last()]/a")), follow=True)
    )

    def parse_item(self, response):
        yield {
            'Name': response.xpath("//div[@class='save-share']/following-sibling::h1/text()").get()
        }    

这是输出：

2021-12-29 10:42:18 [scrapy.core.engine] INFO: Spider opened
2021-12-29 10:42:18 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2021-12-29 10:42:18 [scrapy.extensions.telnet] INFO: Telnet console listening on 127.0.0.1:6023
2021-12-29 10:42:18 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://www.edgeprop.my/buy/malaysia/all-residential> (referer: None)
2021-12-29 10:42:18 [scrapy.core.engine] INFO: Closing spider (finished)
2021-12-29 10:42:18 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 328,
 'downloader/request_count': 1,
 'downloader/request_method_count/GET': 1,
 'downloader/response_bytes': 4126,
 'downloader/response_count': 1,
 'downloader/response_status_count/200': 1,
 'elapsed_time_seconds': 0.237148,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2021, 12, 29, 2, 42, 18, 936521),
 'httpcompression/response_bytes': 10918,
 'httpcompression/response_count': 1,
 'log_count/DEBUG': 1,
 'log_count/INFO': 10,
 'response_received_count': 1,
 'scheduler/dequeued': 1,
 'scheduler/dequeued/memory': 1,
 'scheduler/enqueued': 1,
 'scheduler/enqueued/memory': 1,
 'start_time': datetime.datetime(2021, 12, 29, 2, 42, 18, 699373)}
2021-12-29 10:42:18 [scrapy.core.engine] INFO: Spider closed (finished)

Answer 1

这比你想象的要容易得多；您可以从网页的响应开始，并通过 json 请求进行抓取。

接下来的页面也由有效负载提供，以及每页的所有属性。我已经构建了一个简单的抓取工具来抓取所有响应，您只需要解析字典。请注意，您可能会被重定向，因此我添加了 DOWNLOAD_DELAY，这可能会有所帮助。其他一切都是不言自明的。

import scrapy
from scrapy.loader import ItemLoader
from itemloaders.processors import TakeFirst
from scrapy.item import Field
from scrapy.crawler import CrawlerProcess
from scrapy.http.request.form import FormRequest
from scrapy_splash import SplashRequest
from scrapy_splash.request import SplashFormRequest
class MalItem(scrapy.Item):
    listings = Field(output_processor = TakeFirst())


class MalSpider(scrapy.Spider):
    name = 'Mala'
    
    #start_urls = []
    start_urls = ['https://www.edgeprop.my/jwdsonic/api/v1/property/search?&listing_type=sale&state=Malaysia&property_type=rl&start=0&size=20']
    #for i in range(0, 5):
    #    start_urls.append(f'https://www.edgeprop.my/jwdsonic/api/v1/property/search?&listing_type=sale&state=Malaysia&property_type=rl&start={i}&size=20')

    custom_settings = {
        #'LOG_LEVEL': 'CRITICAL',
        'ROBOTSTXT_OBEY': False,
        'USER_AGENT': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36',
        'CONCURRENT_REQUESTS': 100,
        'CONCURRENT_REQUESTS_PER_IP': 100,
        'DOWNLOAD_DELAY':3
    }
    def start_requests(self):
        for url in self.start_urls:
            for i in range(0, 7709):
                yield scrapy.FormRequest(
                url, 
                method='GET',
                formdata = {
                    'listing_type': 'sale',
                    'state': 'Malaysia',
                    'property_type': 'rl',
                    'start': str(i),
                    'size': '20'
                },
                callback = self.parse
            )
    
    def parse(self, response):
        links = response.json().get('property')
        for stuff in links:
            loader = ItemLoader(MalItem())
            loader.add_value('listings', stuff)
            yield loader.load_item()

process = CrawlerProcess(

    settings = {
        "FEED_URI":'stuff.jl',
        "FEED_FORMAT":'jsonlines'
    }
)