python scrapy 网络采集使用代理的方法

# Importing base64 library because we'll need it ONLY in case if the proxy we are going to use requires authentication
import base64
# Start your middleware class
class ProxyMiddleware(object):
    # overwrite process request
    def process_request(self, request, spider):
        # Set the location of the proxy
        request.meta['proxy'] = "http://YOUR_PROXY_IP:PORT"
        # Use the following lines if your proxy requires authentication
        proxy_user_pass = "USERNAME:PASSWORD"
        # setup basic authentication for the proxy
        encoded_user_pass = base64.encodestring(proxy_user_pass)
        request.headers['Proxy-Authorization'] = 'Basic ' + encoded_user_pass

DOWNLOADER_MIDDLEWARES = {
    'scrapy.contrib.downloadermiddleware.httpproxy.HttpProxyMiddleware': 110,
    'project_name.middlewares.ProxyMiddleware': 100,

from scrapy.spider import BaseSpider
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.http import Request
class TestSpider(CrawlSpider):
    name = "test"
    domain_name = "whatismyip.com"
    # The following url is subject to change, you can get the last updated one from here :
    # http://www.whatismyip.com/faq/automation.asp
    start_urls = ["http://xujian.info"]
    def parse(self, response):
        open('test.html', 'wb').write(response.body)