有人可以帮我解决这个问题,我一直在搜索此信息 2 天,没有运气。
我有一个带有 1 个字段的项目作为另一个项目的列表。蜘蛛工作正常,但在输出文件中我得到了这个项目的所有行。
例如,我需要将 json 打印为:
{"id": "AAAA", "details": [
{"date" : "2013-01-10", type="A"},
{"date" : "2013-02-10", type="B"},
{"date" : "2013-03-10", type="C"},
{"date" : "2013-04-10"}, type="D"]}
但我得到:
{"id": "AAAA", "details": [
{"date" : "2013-01-10", type="A"}]}
{"id": "AAAA", "details": [
{"date" : "2013-01-10", type="A"},
{"date" : "2013-02-10", type="B"}]}
{"id": "AAAA", "details": [
{"date" : "2013-01-10", type="A"},
{"date" : "2013-02-10", type="B"},
{"date" : "2013-03-10", type="C"}
]}
{"id": "AAAA", "details": [
{"date" : "2013-01-10", type="A"},
{"date" : "2013-02-10", type="B"},
{"date" : "2013-03-10", type="C"},
{"date" : "2013-04-10"}, type="D"]}
我使用一个函数来更新我的父项:
def rePackIt(parent, item):
if 'details' in parent:
items = parent.get('details')
else:
items = []
items.append(dict(item))
parent['details'] = items
return parent
在解析函数中我做:
parent = ParentItem()
parent['id'] = self.param # actually I parse a text file with many IDs
parent['details'] = []
yield FormRequest.from_response(response,
formname='...',
formdata={'...':'...', '...': parent['id'],
'...':''},
meta = {'parent': parent, 'dont_merge_cookies': True},
callback=self.parse1)
def parse1(self, response):
parent = response.meta['parent']
sel = HtmlXPathSelector(response)
records = sel.select('//ul[@class="...."]')
for record in records:
item = DetailItem()
item['type'] = record.select('child...')
doc_link = record.select('child.../a/@href').extract()
yield Request(doc_link,
callback=self.parse2,
method='GET',
headers={...},
meta={'dont_merge_cookies': True, 'cookiejar': cookieJar, 'item' : item, 'parent' : parent}
)
def parse2(self, response):
item = response.meta['item']
parent = response.meta['parent']
sel = HtmlXPathSelector(response)
# some other parsing code
item['date'] = cell.select('span[1]/text()[1]').extact()
rePackIt(parent, item)
return parent