python - 如何为通过 socksipy 发出请求的 scrapy 编写 DownloadHandler？

Question

我正在尝试在 Tor 上使用 scrapy。我一直在努力思考如何为使用 socksipy 连接的 scrapy 编写 DownloadHandler。

Scrapy 的 HTTP11DownloadHandler 在这里:https://github.com/scrapy/scrapy/blob/master/scrapy/core/downloader/handlers/http11.py

以下是创建自定义下载处理程序的示例: https://github.com/scrapinghub/scrapyjs/blob/master/scrapyjs/dhandler.py

这是创建 SocksiPyConnection 类的代码:http://blog.databigbang.com/distributed-scraping-with-multiple-tor-circuits/

class SocksiPyConnection(httplib.HTTPConnection):
    def __init__(self, proxytype, proxyaddr, proxyport = None, rdns = True, username = None, password = None, *args, **kwargs):
        self.proxyargs = (proxytype, proxyaddr, proxyport, rdns, username, password)
        httplib.HTTPConnection.__init__(self, *args, **kwargs)

    def connect(self):
        self.sock = socks.socksocket()
        self.sock.setproxy(*self.proxyargs)
        if isinstance(self.timeout, float):
            self.sock.settimeout(self.timeout)
        self.sock.connect((self.host, self.port))

由于 scrapy 代码中扭曲 react 器的复杂性，我不知道如何将 socksipy 插入其中。有什么想法吗？

请不要用类似 privoxy 的替代方案来回答或发布回答说“scrapy 不适用于 socks 代理”——我知道，这就是为什么我试图编写一个使用 socksipy 发出请求的自定义下载器。

Answer 1

我能够使用 https://github.com/habnabit/txsocksx 完成这项工作.

完成 pip install txsocksx 后，我需要用 txsocksx.http.SOCKS5Agent 替换 scrapy 的 ScrapyAgent。

我只是从 scrapy/core/downloader/handlers/http.py 复制了 HTTP11DownloadHandler 和 ScrapyAgent 的代码，将它们子类化并编写这段代码:

class TorProxyDownloadHandler(HTTP11DownloadHandler):

    def download_request(self, request, spider):
        """Return a deferred for the HTTP download"""
        agent = ScrapyTorAgent(contextFactory=self._contextFactory, pool=self._pool)
        return agent.download_request(request)


class ScrapyTorAgent(ScrapyAgent):
    def _get_agent(self, request, timeout):
        bindaddress = request.meta.get('bindaddress') or self._bindAddress
        proxy = request.meta.get('proxy')
        if proxy:
            _, _, proxyHost, proxyPort, proxyParams = _parse(proxy)
            scheme = _parse(request.url)[0]
            omitConnectTunnel = proxyParams.find('noconnect') >= 0
            if  scheme == 'https' and not omitConnectTunnel:
                proxyConf = (proxyHost, proxyPort,
                             request.headers.get('Proxy-Authorization', None))
                return self._TunnelingAgent(reactor, proxyConf,
                    contextFactory=self._contextFactory, connectTimeout=timeout,
                    bindAddress=bindaddress, pool=self._pool)
            else:
                _, _, host, port, proxyParams = _parse(request.url)
                proxyEndpoint = TCP4ClientEndpoint(reactor, proxyHost, proxyPort,
                    timeout=timeout, bindAddress=bindaddress)
                agent = SOCKS5Agent(reactor, proxyEndpoint=proxyEndpoint)
                return agent

        return self._Agent(reactor, contextFactory=self._contextFactory,
            connectTimeout=timeout, bindAddress=bindaddress, pool=self._pool)

在 settings.py 中，需要这样的东西:

DOWNLOAD_HANDLERS = {
    'http': 'crawler.http.TorProxyDownloadHandler'
}

现在通过像 Tor 这样的 socks 代理使用 Scrapy 进行代理。