My parse looks like this:
def parse(self, response):
hxs = HtmlXPathSelector(response)
titles = hxs.select("//tr/td")
items = []
for titles in titles:
item = MyItem()
item['title'] = titles.select('h3/a/text()').extract()
items.append(item)
return items
Why does it output json like this:
[{"title": ["random title #1"]},
{"title": ["random title #2"]}]
titles.select('h3/a/text()').extract()
returns a list, so you get a list. Scrapy doesn't make any assumptions about your item's structure.
The quick fix would be to just get the first result:
item['title'] = titles.select('h3/a/text()').extract()[0]
A better solution would be to use an item loader and use TakeFirst()
as an output processor:
from scrapy.contrib.loader import XPathItemLoader
from scrapy.contrib.loader.processor import TakeFirst, MapCompose
class YourItemLoader(XPathItemLoader):
default_item_class = YourItemClass
default_input_processor = MapCompose(unicode.strip)
default_output_processor = TakeFirst()
# title_in = MapCompose(unicode.strip)
And load the item that way:
def parse(self, response):
hxs = HtmlXPathSelector(response)
for title in hxs.select("//tr/td"):
loader = YourItemLoader(selector=title, response=response)
loader.add_xpath('title', 'h3/a/text()')
yield loader.load_item()
As an alternative simple answer you can write a helper function like this:
def extractor(xpathselector, selector):
"""
Helper function that extract info from xpathselector object
using the selector constrains.
"""
val = xpathselector.select(selector).extract()
return val[0] if val else None
and call it like this:
item['title'] = extractor(titles, 'h3/a/text()')
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