当我们使用scrapy框架爬取网站的时候，我们会有一个入口的url，一个名为start_urls,我们爬取的第一个网页是从这一开始的。

需求：

　　现在我们有一个这样的需求，比如说我们对起始的URL有一个相对应的处理函数，对后面的爬取的url又要进行一个新的处理那么我们需要两个处理函数。

　　如果我们想对起始的url的处理函数不为默认的parser那我们应该怎么修改呢

在父类的中我们可以看到一个名为start_requests的函数他就控制了起始url使用什么调用什么回调函数所以我们只要重写他就可以了，在scrapy中yield一个Request对象（已经可以设置callback了）

那么scrapy框架会自动将其放入调度器，然后爬取

class ZhipinSpider(scrapy.Spider):    name = 'zhipin'    allowed_domains = ['zhipin.com']    start_urls = ['xxx.com']    # 方案一    def start_requests(self):            for url in self.start_urls:                yield Request(url=url,callback=self.parse2)        # 方案二    def start_requests(self):    req_list = []    for url in self.start_urls:        req_list.append(Request(url=url,callback=self.parse2))    return req_list    def parser(self, response):        pass    def parser2(self, response):        pass

 

这里使用yield和返回一个列表的效果是一样的，因为在scrapy内部会使用iter()方法最后返回的都是一个可迭代对象。

 

解析器

parser中的参数是一个response对象我们需要用解析器来对其进行解析

有两种方式一种是他内部实现了我们可以直接对其进行解析

response.xpath('//div[@id='content-list']/div[@class='item']')

　　

还有一种是导入模块的方式进行解析：

from scrapy.selector import HtmlXPathSelector。。。def parser(self, response):    hxs = HtmlXPathSelector(respone=response)    items = hxs.xpath("//div[@id='content-list']/div[@class='item']")

 

查找规则：

hxs = Selector(response=response).xpath('//div') # 去子子孙孙下找div标签 hxs = Selector(response=response).xpath('/div')  # 去儿子下找div 标签hxs = Selector(response=response).xpath('//div[2]') # 去子子孙孙下找第二个div标签hxs = Selector(response=response).xpath('//a[@id]') # 找有id属性的a标签 hxs = Selector(response=response).xpath('//a[@id="i1"]') # 找id="i1"的所有a标签（id不重复，但是可能不是id的情况下）hxs = Selector(response=response).xpath('//a[@href="link.html"][@id="i1"]') # 且的关系hxs = Selector(response=response).xpath('//a[contains(@href, "link")]') # 有这两个属性的a标签hxs = Selector(response=response).xpath('//a[re:test(@id, "i\d+")]') # 使用正则来匹配

　　

解析得到的类型：

标签对象：  xpath('/html/body/ul/li/a/@href')列表：     xpath('/html/body/ul/li/a/@href').extract()值：       xpath('//body/ul/li/a/@href').extract_first()

　　

如何独立使用scrapy的解析器：

from scrapy.selector import Selector, HtmlXPathSelectorfrom scrapy.http import HtmlResponsehtml = """            
                              
      
            
       
first item
            
       
first item
            
       
second itemvv
        
      
        
      
       second item
      
    """response = HtmlResponse(url='http://example.com', body=html,encoding='utf-8')obj = response.xpath('//a[@id="i1"]/text()').extract_first()print(obj)

 

格式化处理items持久化处理pipleline

上述实例只是简单的处理，所以在parse方法中直接处理。如果对于想要获取更多的数据处理，则可以利用Scrapy的items将数据格式化，然后统一交由pipelines来处理。

 当yield一个item对象时会直接去pipeline中执行持久化操作

import scrapyfrom scrapy.selector import HtmlXPathSelectorfrom scrapy.http.request import Requestfrom scrapy.http.cookies import CookieJarfrom scrapy import FormRequestclass XiaoHuarSpider(scrapy.Spider):    # 爬虫应用的名称，通过此名称启动爬虫命令    name = "xiaohuar"    # 允许的域名    allowed_domains = ["xiaohuar.com"]    start_urls = [        "http://www.xiaohuar.com/list-1-1.html",    ]    # custom_settings = {
         #     'ITEM_PIPELINES':{
         #         'spider1.pipelines.JsonPipeline': 100    #     }    # }    has_request_set = {}    def parse(self, response):        # 分析页面        # 找到页面中符合规则的内容（校花图片），保存        # 找到所有的a标签，再访问其他a标签，一层一层的搞下去        hxs = HtmlXPathSelector(response)        items = hxs.select('//div[@class="item_list infinite_scroll"]/div')        for item in items:            src = item.select('.//div[@class="img"]/a/img/@src').extract_first()            name = item.select('.//div[@class="img"]/span/text()').extract_first()            school = item.select('.//div[@class="img"]/div[@class="btns"]/a/text()').extract_first()            url = "http://www.xiaohuar.com%s" % src            from ..items import XiaoHuarItem            obj = XiaoHuarItem(name=name, school=school, url=url)            yield obj        urls = hxs.select('//a[re:test(@href, "http://www.xiaohuar.com/list-1-\d+.html")]/@href')        for url in urls:            key = self.md5(url)            if key in self.has_request_set:                pass            else:                self.has_request_set[key] = url                req = Request(url=url,method='GET',callback=self.parse)                yield req    @staticmethod    def md5(val):        import hashlib        ha = hashlib.md5()        ha.update(bytes(val, encoding='utf-8'))        key = ha.hexdigest()        return key

import scrapyclass XiaoHuarItem(scrapy.Item):    name = scrapy.Field()    school = scrapy.Field()    url = scrapy.Field()

import jsonimport osimport requestsclass JsonPipeline(object):    def __init__(self):        self.file = open('xiaohua.txt', 'w')    def process_item(self, item, spider):        v = json.dumps(dict(item), ensure_ascii=False)        self.file.write(v)        self.file.write('\n')        self.file.flush()        return itemclass FilePipeline(object):    def __init__(self):        if not os.path.exists('imgs'):            os.makedirs('imgs')    def process_item(self, item, spider):        response = requests.get(item['url'], stream=True)        file_name = '%s_%s.jpg' % (item['name'], item['school'])        with open(os.path.join('imgs', file_name), mode='wb') as f:            f.write(response.content)        return item

ITEM_PIPELINES = {   'spider1.pipelines.JsonPipeline': 100,   'spider1.pipelines.FilePipeline': 300,}# 每行后面的整型值，确定了他们运行的顺序，item按数字从低到高的顺序，通过pipeline，通常将这些数字定义在0-1000范围内。

　　

pipeline更多的方法

from scrapy.exceptions import DropItemclass CustomPipeline(object):    def __init__(self,v):        self.value = v    def process_item(self, item, spider):        # 操作并进行持久化        # return表示会被后续的pipeline继续处理        return item        # 表示将item丢弃，不会被后续pipeline处理        # raise DropItem()    @classmethod    def from_crawler(cls, crawler):        """        初始化时候，用于创建pipeline对象        :param crawler:         :return:         """        val = crawler.settings.getint('MMMM')        return cls(val)    def open_spider(self,spider):        """        爬虫开始执行时，调用        :param spider:         :return:         """        print('000000')    def close_spider(self,spider):        """        爬虫关闭时，被调用        :param spider:         :return:         """        print('111111')

 

去重：

要在settings文件中配置相应的类

DUPEFILTER_CLASS = 'scrapy.dupefilter.RFPDupeFilter'DUPEFILTER_DEBUG = FalseJOBDIR = "保存范文记录的日志路径，如：/root/"  # 最终路径为 /root/requests.seen

　　

自定义：

class RepeatUrl:    def __init__(self):        self.visited_url = set()    @classmethod    def from_settings(cls, settings):        """        初始化时，调用        :param settings:         :return:         """        return cls()    def request_seen(self, request):        """        检测当前请求是否已经被访问过        :param request:         :return: True表示已经访问过；False表示未访问过        """        if request.url in self.visited_url:            return True        self.visited_url.add(request.url)        return False    def open(self):        """        开始爬去请求时，调用        :return:         """        print('open replication')    def close(self, reason):        """        结束爬虫爬取时，调用        :param reason:         :return:         """        print('close replication')    def log(self, request, spider):        """        记录日志        :param request:         :param spider:         :return:         """        print('repeat', request.url)

 

中间件

class SpiderMiddleware(object):    def process_spider_input(self,response, spider):        """        下载完成，执行，然后交给parse处理        :param response:         :param spider:         :return:         """        pass    def process_spider_output(self,response, result, spider):        """        spider处理完成，返回时调用        :param response:        :param result:        :param spider:        :return: 必须返回包含 Request 或 Item 对象的可迭代对象(iterable)        """        return result    def process_spider_exception(self,response, exception, spider):        """        异常调用        :param response:        :param exception:        :param spider:        :return: None,继续交给后续中间件处理异常；含 Response 或 Item 的可迭代对象(iterable)，交给调度器或pipeline        """        return None    def process_start_requests(self,start_requests, spider):        """        爬虫启动时调用        :param start_requests:        :param spider:        :return: 包含 Request 对象的可迭代对象        """        return start_requests爬虫中间件

class DownMiddleware1(object):    def process_request(self, request, spider):        """        请求需要被下载时，经过所有下载器中间件的process_request调用        :param request:         :param spider:         :return:              None,继续后续中间件去下载；            Response对象，停止process_request的执行，开始执行process_response            Request对象，停止中间件的执行，将Request重新调度器            raise IgnoreRequest异常，停止process_request的执行，开始执行process_exception        """        pass    def process_response(self, request, response, spider):        """        spider处理完成，返回时调用        :param response:        :param result:        :param spider:        :return:             Response 对象：转交给其他中间件process_response            Request 对象：停止中间件，request会被重新调度下载            raise IgnoreRequest 异常：调用Request.errback        """        print('response1')        return response    def process_exception(self, request, exception, spider):        """        当下载处理器(download handler)或 process_request() (下载中间件)抛出异常        :param response:        :param exception:        :param spider:        :return:             None：继续交给后续中间件处理异常；            Response对象：停止后续process_exception方法            Request对象：停止中间件，request将会被重新调用下载        """        return None下载器中间件

 

 

 

自定制命令

• 在spiders同级创建任意目录，如：commands
• 在其中创建 crawlall.py 文件 （此处文件名就是自定义的命令）

如果想运行所有的爬虫：

from scrapy.commands import ScrapyCommand    from scrapy.utils.project import get_project_settings    class Command(ScrapyCommand):        requires_project = True        def syntax(self):            return '[options]'        def short_desc(self):            return 'Runs all of the spiders'        def run(self, args, opts):            spider_list = self.crawler_process.spiders.list()            for name in spider_list:                self.crawler_process.crawl(name, **opts.__dict__)            self.crawler_process.start()crawlall.py

• 在settings.py 中添加配置 COMMANDS_MODULE = '项目名称.目录名称'
• 在项目目录执行命令：scrapy crawlall 

其他

# -*- coding: utf-8 -*-# Scrapy settings for step8_king project## For simplicity, this file contains only settings considered important or# commonly used. You can find more settings consulting the documentation:##     http://doc.scrapy.org/en/latest/topics/settings.html#     http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html#     http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html# 1. 爬虫名称BOT_NAME = 'step8_king'# 2. 爬虫应用路径SPIDER_MODULES = ['step8_king.spiders']NEWSPIDER_MODULE = 'step8_king.spiders'# Crawl responsibly by identifying yourself (and your website) on the user-agent# 3. 客户端 user-agent请求头# USER_AGENT = 'step8_king (+http://www.yourdomain.com)'# Obey robots.txt rules# 4. 禁止爬虫配置# ROBOTSTXT_OBEY = False# Configure maximum concurrent requests performed by Scrapy (default: 16)# 5. 并发请求数# CONCURRENT_REQUESTS = 4# Configure a delay for requests for the same website (default: 0)# See http://scrapy.readthedocs.org/en/latest/topics/settings.html#download-delay# See also autothrottle settings and docs# 6. 延迟下载秒数# DOWNLOAD_DELAY = 2# The download delay setting will honor only one of:# 7. 单域名访问并发数，并且延迟下次秒数也应用在每个域名# CONCURRENT_REQUESTS_PER_DOMAIN = 2# 单IP访问并发数，如果有值则忽略：CONCURRENT_REQUESTS_PER_DOMAIN，并且延迟下次秒数也应用在每个IP# CONCURRENT_REQUESTS_PER_IP = 3# Disable cookies (enabled by default)# 8. 是否支持cookie，cookiejar进行操作cookie# COOKIES_ENABLED = True# COOKIES_DEBUG = True# Disable Telnet Console (enabled by default)# 9. Telnet用于查看当前爬虫的信息，操作爬虫等...#    使用telnet ip port ，然后通过命令操作# TELNETCONSOLE_ENABLED = True# TELNETCONSOLE_HOST = '127.0.0.1'# TELNETCONSOLE_PORT = [6023,]# 10. 默认请求头# Override the default request headers:# DEFAULT_REQUEST_HEADERS = {
     #     'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',#     'Accept-Language': 'en',# }# Configure item pipelines# See http://scrapy.readthedocs.org/en/latest/topics/item-pipeline.html# 11. 定义pipeline处理请求# ITEM_PIPELINES = {
     #    'step8_king.pipelines.JsonPipeline': 700,#    'step8_king.pipelines.FilePipeline': 500,# }# 12. 自定义扩展，基于信号进行调用# Enable or disable extensions# See http://scrapy.readthedocs.org/en/latest/topics/extensions.html# EXTENSIONS = {
     #     # 'step8_king.extensions.MyExtension': 500,# }# 13. 爬虫允许的最大深度，可以通过meta查看当前深度；0表示无深度# DEPTH_LIMIT = 3# 14. 爬取时，0表示深度优先Lifo(默认)；1表示广度优先FiFo# 后进先出，深度优先# DEPTH_PRIORITY = 0# SCHEDULER_DISK_QUEUE = 'scrapy.squeue.PickleLifoDiskQueue'# SCHEDULER_MEMORY_QUEUE = 'scrapy.squeue.LifoMemoryQueue'# 先进先出，广度优先# DEPTH_PRIORITY = 1# SCHEDULER_DISK_QUEUE = 'scrapy.squeue.PickleFifoDiskQueue'# SCHEDULER_MEMORY_QUEUE = 'scrapy.squeue.FifoMemoryQueue'# 15. 调度器队列# SCHEDULER = 'scrapy.core.scheduler.Scheduler'# from scrapy.core.scheduler import Scheduler# 16. 访问URL去重# DUPEFILTER_CLASS = 'step8_king.duplication.RepeatUrl'# Enable and configure the AutoThrottle extension (disabled by default)# See http://doc.scrapy.org/en/latest/topics/autothrottle.html"""17. 自动限速算法    from scrapy.contrib.throttle import AutoThrottle    自动限速设置    1. 获取最小延迟 DOWNLOAD_DELAY    2. 获取最大延迟 AUTOTHROTTLE_MAX_DELAY    3. 设置初始下载延迟 AUTOTHROTTLE_START_DELAY    4. 当请求下载完成后，获取其"连接"时间 latency，即：请求连接到接受到响应头之间的时间    5. 用于计算的... AUTOTHROTTLE_TARGET_CONCURRENCY    target_delay = latency / self.target_concurrency    new_delay = (slot.delay + target_delay) / 2.0 # 表示上一次的延迟时间    new_delay = max(target_delay, new_delay)    new_delay = min(max(self.mindelay, new_delay), self.maxdelay)    slot.delay = new_delay"""# 开始自动限速# AUTOTHROTTLE_ENABLED = True# The initial download delay# 初始下载延迟# AUTOTHROTTLE_START_DELAY = 5# The maximum download delay to be set in case of high latencies# 最大下载延迟# AUTOTHROTTLE_MAX_DELAY = 10# The average number of requests Scrapy should be sending in parallel to each remote server# 平均每秒并发数# AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0# Enable showing throttling stats for every response received:# 是否显示# AUTOTHROTTLE_DEBUG = True# Enable and configure HTTP caching (disabled by default)# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings"""18. 启用缓存    目的用于将已经发送的请求或相应缓存下来，以便以后使用        from scrapy.downloadermiddlewares.httpcache import HttpCacheMiddleware    from scrapy.extensions.httpcache import DummyPolicy    from scrapy.extensions.httpcache import FilesystemCacheStorage"""# 是否启用缓存策略# HTTPCACHE_ENABLED = True# 缓存策略：所有请求均缓存，下次在请求直接访问原来的缓存即可# HTTPCACHE_POLICY = "scrapy.extensions.httpcache.DummyPolicy"# 缓存策略：根据Http响应头：Cache-Control、Last-Modified 等进行缓存的策略# HTTPCACHE_POLICY = "scrapy.extensions.httpcache.RFC2616Policy"# 缓存超时时间# HTTPCACHE_EXPIRATION_SECS = 0# 缓存保存路径# HTTPCACHE_DIR = 'httpcache'# 缓存忽略的Http状态码# HTTPCACHE_IGNORE_HTTP_CODES = []# 缓存存储的插件# HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'"""19. 代理，需要在环境变量中设置    from scrapy.contrib.downloadermiddleware.httpproxy import HttpProxyMiddleware        方式一：使用默认        os.environ        {            http_proxy:http://root:woshiniba@192.168.11.11:9999/            https_proxy:http://192.168.11.11:9999/        }    方式二：使用自定义下载中间件        def to_bytes(text, encoding=None, errors='strict'):        if isinstance(text, bytes):            return text        if not isinstance(text, six.string_types):            raise TypeError('to_bytes must receive a unicode, str or bytes '                            'object, got %s' % type(text).__name__)        if encoding is None:            encoding = 'utf-8'        return text.encode(encoding, errors)            class ProxyMiddleware(object):        def process_request(self, request, spider):            PROXIES = [                {'ip_port': '111.11.228.75:80', 'user_pass': ''},                {'ip_port': '120.198.243.22:80', 'user_pass': ''},                {'ip_port': '111.8.60.9:8123', 'user_pass': ''},                {'ip_port': '101.71.27.120:80', 'user_pass': ''},                {'ip_port': '122.96.59.104:80', 'user_pass': ''},                {'ip_port': '122.224.249.122:8088', 'user_pass': ''},            ]            proxy = random.choice(PROXIES)            if proxy['user_pass'] is not None:                request.meta['proxy'] = to_bytes（"http://%s" % proxy['ip_port']）                encoded_user_pass = base64.encodestring(to_bytes(proxy['user_pass']))                request.headers['Proxy-Authorization'] = to_bytes('Basic ' + encoded_user_pass)                print "**************ProxyMiddleware have pass************" + proxy['ip_port']            else:                print "**************ProxyMiddleware no pass************" + proxy['ip_port']                request.meta['proxy'] = to_bytes("http://%s" % proxy['ip_port'])        DOWNLOADER_MIDDLEWARES = {       'step8_king.middlewares.ProxyMiddleware': 500,    }    """"""20. Https访问    Https访问时有两种情况：    1. 要爬取网站使用的可信任证书(默认支持)        DOWNLOADER_HTTPCLIENTFACTORY = "scrapy.core.downloader.webclient.ScrapyHTTPClientFactory"        DOWNLOADER_CLIENTCONTEXTFACTORY = "scrapy.core.downloader.contextfactory.ScrapyClientContextFactory"            2. 要爬取网站使用的自定义证书        DOWNLOADER_HTTPCLIENTFACTORY = "scrapy.core.downloader.webclient.ScrapyHTTPClientFactory"        DOWNLOADER_CLIENTCONTEXTFACTORY = "step8_king.https.MySSLFactory"                # https.py        from scrapy.core.downloader.contextfactory import ScrapyClientContextFactory        from twisted.internet.ssl import (optionsForClientTLS, CertificateOptions, PrivateCertificate)                class MySSLFactory(ScrapyClientContextFactory):            def getCertificateOptions(self):                from OpenSSL import crypto                v1 = crypto.load_privatekey(crypto.FILETYPE_PEM, open('/Users/wupeiqi/client.key.unsecure', mode='r').read())                v2 = crypto.load_certificate(crypto.FILETYPE_PEM, open('/Users/wupeiqi/client.pem', mode='r').read())                return CertificateOptions(                    privateKey=v1,  # pKey对象                    certificate=v2,  # X509对象                    verify=False,                    method=getattr(self, 'method', getattr(self, '_ssl_method', None))                )    其他：        相关类            scrapy.core.downloader.handlers.http.HttpDownloadHandler            scrapy.core.downloader.webclient.ScrapyHTTPClientFactory            scrapy.core.downloader.contextfactory.ScrapyClientContextFactory        相关配置            DOWNLOADER_HTTPCLIENTFACTORY            DOWNLOADER_CLIENTCONTEXTFACTORY""""""21. 爬虫中间件    class SpiderMiddleware(object):        def process_spider_input(self,response, spider):            '''            下载完成，执行，然后交给parse处理            :param response:             :param spider:             :return:             '''            pass            def process_spider_output(self,response, result, spider):            '''            spider处理完成，返回时调用            :param response:            :param result:            :param spider:            :return: 必须返回包含 Request 或 Item 对象的可迭代对象(iterable)            '''            return result            def process_spider_exception(self,response, exception, spider):            '''            异常调用            :param response:            :param exception:            :param spider:            :return: None,继续交给后续中间件处理异常；含 Response 或 Item 的可迭代对象(iterable)，交给调度器或pipeline            '''            return None                def process_start_requests(self,start_requests, spider):            '''            爬虫启动时调用            :param start_requests:            :param spider:            :return: 包含 Request 对象的可迭代对象            '''            return start_requests        内置爬虫中间件：        'scrapy.contrib.spidermiddleware.httperror.HttpErrorMiddleware': 50,        'scrapy.contrib.spidermiddleware.offsite.OffsiteMiddleware': 500,        'scrapy.contrib.spidermiddleware.referer.RefererMiddleware': 700,        'scrapy.contrib.spidermiddleware.urllength.UrlLengthMiddleware': 800,        'scrapy.contrib.spidermiddleware.depth.DepthMiddleware': 900,"""# from scrapy.contrib.spidermiddleware.referer import RefererMiddleware# Enable or disable spider middlewares# See http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.htmlSPIDER_MIDDLEWARES = {   # 'step8_king.middlewares.SpiderMiddleware': 543,}"""22. 下载中间件    class DownMiddleware1(object):        def process_request(self, request, spider):            '''            请求需要被下载时，经过所有下载器中间件的process_request调用            :param request:            :param spider:            :return:                None,继续后续中间件去下载；                Response对象，停止process_request的执行，开始执行process_response                Request对象，停止中间件的执行，将Request重新调度器                raise IgnoreRequest异常，停止process_request的执行，开始执行process_exception            '''            pass                    def process_response(self, request, response, spider):            '''            spider处理完成，返回时调用            :param response:            :param result:            :param spider:            :return:                Response 对象：转交给其他中间件process_response                Request 对象：停止中间件，request会被重新调度下载                raise IgnoreRequest 异常：调用Request.errback            '''            print('response1')            return response            def process_exception(self, request, exception, spider):            '''            当下载处理器(download handler)或 process_request() (下载中间件)抛出异常            :param response:            :param exception:            :param spider:            :return:                None：继续交给后续中间件处理异常；                Response对象：停止后续process_exception方法                Request对象：停止中间件，request将会被重新调用下载            '''            return None        默认下载中间件    {        'scrapy.contrib.downloadermiddleware.robotstxt.RobotsTxtMiddleware': 100,        'scrapy.contrib.downloadermiddleware.httpauth.HttpAuthMiddleware': 300,        'scrapy.contrib.downloadermiddleware.downloadtimeout.DownloadTimeoutMiddleware': 350,        'scrapy.contrib.downloadermiddleware.useragent.UserAgentMiddleware': 400,        'scrapy.contrib.downloadermiddleware.retry.RetryMiddleware': 500,        'scrapy.contrib.downloadermiddleware.defaultheaders.DefaultHeadersMiddleware': 550,        'scrapy.contrib.downloadermiddleware.redirect.MetaRefreshMiddleware': 580,        'scrapy.contrib.downloadermiddleware.httpcompression.HttpCompressionMiddleware': 590,        'scrapy.contrib.downloadermiddleware.redirect.RedirectMiddleware': 600,        'scrapy.contrib.downloadermiddleware.cookies.CookiesMiddleware': 700,        'scrapy.contrib.downloadermiddleware.httpproxy.HttpProxyMiddleware': 750,        'scrapy.contrib.downloadermiddleware.chunked.ChunkedTransferMiddleware': 830,        'scrapy.contrib.downloadermiddleware.stats.DownloaderStats': 850,        'scrapy.contrib.downloadermiddleware.httpcache.HttpCacheMiddleware': 900,    }"""# from scrapy.contrib.downloadermiddleware.httpauth import HttpAuthMiddleware# Enable or disable downloader middlewares# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html# DOWNLOADER_MIDDLEWARES = {
     #    'step8_king.middlewares.DownMiddleware1': 100,#    'step8_king.middlewares.DownMiddleware2': 500,# }settings