Rastreio não disponível no site ASPX

Question

Jun 01, 2016, 09:38 PM

javascript web-scraping asp.net scrapy python

Rastreio não disponível no site ASPX

Estou raspando o site da Assembléia de Madri, construído em aspx, e não tenho idéia de como simular cliques nos links de onde preciso obter os políticos correspondentes. Eu tentei isso:

import scrapy

class AsambleaMadrid(scrapy.Spider):

name        =   "Asamblea_Madrid"
start_urls  =   ['http://www.asambleamadrid.es/ES/QueEsLaAsamblea/ComposiciondelaAsamblea/LosDiputados/Paginas/RelacionAlfabeticaDiputados.aspx']

def parse(self, response):

    for id in response.css('div#moduloBusqueda div.sangria div.sangria ul li a::attr(id)'):
        target                  =   id.extract()
        url                     =   "http://www.asambleamadrid.es/ES/QueEsLaAsamblea/ComposiciondelaAsamblea/LosDiputados/Paginas/RelacionAlfabeticaDiputados.aspx"

        formdata=   {'__EVENTTARGET': target,
                     '__VIEWSTATE': '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',
                     '__EVENTVALIDATION': '/wEWCALIhqvYAwKh2YVvAuDF1KUDAqCK1bUOAqCKybkPAqCKnbQCAqCKsZEJAvejv84Dtkx5dCFr3QGqQD2wsFQh8nP3iq8',
                     '__VIEWSTATEGENERATOR': 'BAB98CB3',
                     '__REQUESTDIGEST': '0x476239970DCFDABDBBDF638A1F9B026BD43022A10D1D757B05F1071FF3104459B4666F96A47B4845D625BCB2BE0D88C6E150945E8F5D82C189B56A0DA4BC859D'}

        yield scrapy.FormRequest(url=url, formdata= formdata, callback=self.takeEachParty)


def takeEachParty(self, response):

     print response.css('ul.listadoVert02 ul li::text').extract()

Indo para o código-fonte do site, posso ver como os links são e como eles enviam a consulta JavaScript. Este é um dos links que eu preciso acessar:

<a id="ctl00_m_g_36ea0310_893d_4a19_9ed1_88a133d06423_ctl00_Repeater1_ctl00_lnk_Grupo" href="javascript:WebForm_DoPostBackWithOptions(new WebForm_PostBackOptions(&quot;ctl00$m$g_36ea0310_893d_4a19_9ed1_88a133d06423$ctl00$Repeater1$ctl00$lnk_Grupo&quot;, &quot;&quot;, true, &quot;&quot;, &quot;&quot;, false, true))">Grupo Parlamentario Popular de la Asamblea de Madrid</a>

Eu tenho lido muitos artigos sobre, mas provavelmente o problema é minha ignorância em respeito.

Desde já, obrigado.

EDITADO:

SOLUÇÃO: Eu finalmente consegui! Traduzindo o código muito útil de Padraic Cunningham para o Scrapy way. Como especifiquei o problema do Scrapy, quero postar o resultado, caso alguém tenha o mesmo problema que eu.

Então aqui vai:

import scrapy
import js2xml

class AsambleaMadrid(scrapy.Spider):

     name        =   "AsambleaMadrid"
     start_urls  =   ['http://www.asambleamadrid.es/ES/QueEsLaAsamblea/ComposiciondelaAsamblea/LosDiputados/Paginas/RelacionAlfabeticaDiputados.aspx']

    def parse(self, response):

         source  =   response
         hrefs   =   response.xpath("//*[@id='moduloBusqueda']//div[@class='sangria']/ul/li/a/@href").extract()
         form_data = self.validate(source)
         for ref in hrefs:
             # js2xml allows us to parse the JS function and params, and so to grab the __EVENTTARGET
             js_xml            = js2xml.parse(ref)
             _id               = js_xml.xpath(
                            "//identifier[@name='WebForm_PostBackOptions']/following-sibling::arguments/string[starts-with(.,'ctl')]")[0]
             form_data["__EVENTTARGET"] = _id.text

             url_diputado    =   'http://www.asambleamadrid.es/ES/QueEsLaAsamblea/ComposiciondelaAsamblea/LosDiputados/Paginas/RelacionAlfabeticaDiputados.aspx'
             # The proper way to send a POST in scrapy is by using the FormRequest
             yield scrapy.FormRequest(url=url_diputado, formdata=form_data, callback=self.extract_parties, method='POST')

     def validate(self, source):
         # these fields are the minimum required as cannot be hardcoded
         data = {"__VIEWSTATEGENERATOR": source.xpath("//*[@id='__VIEWSTATEGENERATOR']/@value")[0].extract(),
             "__EVENTVALIDATION": source.xpath("//*[@id='__EVENTVALIDATION']/@value")[0].extract(),
             "__VIEWSTATE": source.xpath("//*[@id='__VIEWSTATE']/@value")[0].extract(),
             " __REQUESTDIGEST": source.xpath("//*[@id='__REQUESTDIGEST']/@value")[0].extract()}
         return data

     def extract_parties(self, response):
         source      =   response
         name        =   source.xpath("//ul[@class='listadoVert02']/ul/li/a/text()").extract()
         print name

Espero que esteja claro. Obrigado a todos, de novo!