XMLFeedSpider analizza l'indicatore del gruppo XML xml, scrapy

Ho qualche problema con il selettore xpath in Scrapy. Non riesco ad analizzare i tag multimediali. Potete aiutarmi, alcune idee, qualche esempio di codice. Grazie Questo è il mio ragno

import scrapy
from scrapy.spiders import XMLFeedSpider
from crawler.items import News

class CNNSpider(XMLFeedSpider):
name = "cnn"
start_urls = [
"http://rss.cnn.com/rss/edition.rss", # Top stories
#"http://rss.cnn.com/rss/cnn_latest.rss", # most recerent
]
iterator = "iternodes"  # This is actually unnecessary, since it"s the default value
itertag = "item"

def parse_node(self, response, node):
item = News()
item["title"] = node.xpath("./title/text()").extract()
item["description"] = node.xpath("./description/text()").extract()
item["link"] = node.xpath("./link/text()").extract()
item["media"] = node.xpath("./media:group/media:content/@url").extract()
item["pubDate"] = node.xpath("./pubDate/text()").extract()
print item["media"]

E il mio feed xml:

<item>
<title><![CDATA[More than 200 dead in Mexico quake, buildings toppled]]></title>
<link>http://www.cnn.com/collections/mexico-city-earthquake-intl/</link>
<guid isPermaLink="true">http://www.cnn.com/collections/mexico-city-earthquake-intl/</guid>
<pubDate>Wed, 20 Sep 2017 10:03:24 GMT</pubDate>
<media:group>
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-super-169.jpg" height="619" width="1100" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-large-11.jpg" height="300" width="300" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-vertical-large-gallery.jpg" height="552" width="414" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-video-synd-2.jpg" height="480" width="640" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-live-video.jpg" height="324" width="576" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-t1-main.jpg" height="250" width="250" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-vertical-gallery.jpg" height="360" width="270" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-story-body.jpg" height="169" width="300" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-t1-main.jpg" height="250" width="250" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-assign.jpg" height="186" width="248" />
<media:content medium="image" url="http://i2.cdn.turner.com/cnnnext/dam/assets/170919190244-25-mexico-earthquake-0919-hp-video.jpg" height="144" width="256" />
</media:group>
</item>

risposte:

È necessario utilizzare sotto Xpath

item["media"] = node.xpath("./*[local-name()="group"]/*[local-name()="content"]/@url").extract()

Fondamentalmente il problema è che i nodi utilizzano lo spazio dei nomi. Oppure puoi registrare lo spazio dei nomi all'interno del tuo file parse_node funzione e farlo funzionare

node.register_namespace("media", "http://search.yahoo.com/mrss/")
item["media"] = node.xpath("./media:group/media:content/@url").extract()