• 40.配置完善爬虫代码文件及图片下载文件重命名问题-1


    这里是直接拿之前未配置代码做修改,主要问题就是在piplines中添加修改配置文件(先解决文件下载问题,图片其实也类似)
    效果如图:

    北京造价信息网站爬虫
    
    bjjs.py
    
    # -*- coding: utf-8 -*-
    import scrapy
    import re
    from bjjs_web.items import BjjsWebItem
    class BjjsSpider(scrapy.Spider):
        name = 'bjjs'
        allowed_domains = ['www.bjjs.gov.cn']
        base_url=['http://www.bjjs.gov.cn']
        start_urls = ['http://www.bjjs.gov.cn/bjjs/gcjs/zczjxx/zjxx/48843934-1.shtml']
        custom_settings = {
            "DOWNLOAD_DELAY": 0.5,
            "ITEM_PIPELINES": {
                'bjjs_web.pipelines.MysqlPipeline': 320,
                'bjjs_web.pipelines.MyFilePipeline': 321,
            },
            "DOWNLOADER_MIDDLEWARES": {
                 'bjjs_web.middlewares.BjjsWebDownloaderMiddleware': 500,
            },
        }
        def parse(self, response):
    
            # tag_list=response.xpath("//div[@class='list_box']/ul/li/a/@href").extract()
            # for tag in tag_list:
            #     url=self.base_url[0]+tag
            #     print(url)
            # print('*'*100)
    
            #正则匹配url,标题,时间
            tag_list=re.findall('<li><a href="(.*?)" onclick=".*?" target="_blank" title=".*?">(.*?)</a><span>(.*?)</span></li>',response.text)
            # print(tag_list)
            for tag in tag_list:
                # print(tag)
                item=BjjsWebItem()
    
                url=self.base_url[0]+tag[0]
                print(url)
                item['file_urls']=[url]
                title=tag[1]
                print(title)
                item['title']=title
                time=tag[2]
                print(time)
                item['time']=time
                print('*'*100)
                yield item
    
            #翻页,获取页面总数
            page_num=re.findall(r'<li>(.*?), (.*?)<input class="ipt_txt"',response.text)
            num=page_num[0][0][1:2]
            # print(num)
    
            for i in range(2,int(num)+1):
                url='http://www.bjjs.gov.cn/bjjs/gcjs/zczjxx/zjxx/48843934-{}.shtml'.format(i)
                # print(url)
    
                yield scrapy.Request(url=url,callback=self.parse)
    items.py
    
    
    # -*- coding: utf-8 -*-
    
    # Define here the models for your scraped items
    #
    # See documentation in:
    # https://doc.scrapy.org/en/latest/topics/items.html
    
    import scrapy
    
    
    class BjjsWebItem(scrapy.Item):
        # define the fields for your item here like:
        # name = scrapy.Field()
        file_urls=scrapy.Field()
        title=scrapy.Field()
        time=scrapy.Field()
    middlewares.py
    
    
    # -*- coding: utf-8 -*-
    
    # Define here the models for your spider middleware
    #
    # See documentation in:
    # https://doc.scrapy.org/en/latest/topics/spider-middleware.html
    
    from scrapy import signals
    
    
    class BjjsWebSpiderMiddleware(object):
        # Not all methods need to be defined. If a method is not defined,
        # scrapy acts as if the spider middleware does not modify the
        # passed objects.
    
        @classmethod
        def from_crawler(cls, crawler):
            # This method is used by Scrapy to create your spiders.
            s = cls()
            crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
            return s
    
        def process_spider_input(self, response, spider):
            # Called for each response that goes through the spider
            # middleware and into the spider.
    
            # Should return None or raise an exception.
            return None
    
        def process_spider_output(self, response, result, spider):
            # Called with the results returned from the Spider, after
            # it has processed the response.
    
            # Must return an iterable of Request, dict or Item objects.
            for i in result:
                yield i
    
        def process_spider_exception(self, response, exception, spider):
            # Called when a spider or process_spider_input() method
            # (from other spider middleware) raises an exception.
    
            # Should return either None or an iterable of Response, dict
            # or Item objects.
            pass
    
        def process_start_requests(self, start_requests, spider):
            # Called with the start requests of the spider, and works
            # similarly to the process_spider_output() method, except
            # that it doesn’t have a response associated.
    
            # Must return only requests (not items).
            for r in start_requests:
                yield r
    
        def spider_opened(self, spider):
            spider.logger.info('Spider opened: %s' % spider.name)
    
    
    class BjjsWebDownloaderMiddleware(object):
        # Not all methods need to be defined. If a method is not defined,
        # scrapy acts as if the downloader middleware does not modify the
        # passed objects.
    
        @classmethod
        def from_crawler(cls, crawler):
            # This method is used by Scrapy to create your spiders.
            s = cls()
            crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
            return s
    
        def process_request(self, request, spider):
            # Called for each request that goes through the downloader
            # middleware.
    
            # Must either:
            # - return None: continue processing this request
            # - or return a Response object
            # - or return a Request object
            # - or raise IgnoreRequest: process_exception() methods of
            #   installed downloader middleware will be called
            return None
    
        def process_response(self, request, response, spider):
            # Called with the response returned from the downloader.
    
            # Must either;
            # - return a Response object
            # - return a Request object
            # - or raise IgnoreRequest
            return response
    
        def process_exception(self, request, exception, spider):
            # Called when a download handler or a process_request()
            # (from other downloader middleware) raises an exception.
    
            # Must either:
            # - return None: continue processing this exception
            # - return a Response object: stops process_exception() chain
            # - return a Request object: stops process_exception() chain
            pass
    
        def spider_opened(self, spider):
            spider.logger.info('Spider opened: %s' % spider.name)
    piplines.py
    
    
    # -*- coding: utf-8 -*-
    
    # Define your item pipelines here
    #
    # Don't forget to add your pipeline to the ITEM_PIPELINES setting
    # See: https://doc.scrapy.org/en/latest/topics/item-pipeline.html
    from scrapy.conf import settings
    from scrapy.exceptions import DropItem
    from scrapy.pipelines.files import FilesPipeline
    import pymysql
    import scrapy
    
    class BjjsWebPipeline(object):
        def process_item(self, item, spider):
            return item
    
    # 数据保存mysql
    class MysqlPipeline(object):
    
        def open_spider(self, spider):
            self.host = settings.get('MYSQL_HOST')
            self.port = settings.get('MYSQL_PORT')
            self.user = settings.get('MYSQL_USER')
            self.password = settings.get('MYSQL_PASSWORD')
            self.db = settings.get(('MYSQL_DB'))
            self.table = settings.get('TABLE')
            self.client = pymysql.connect(host=self.host, user=self.user, password=self.password, port=self.port, db=self.db, charset='utf8')
    
        def process_item(self, item, spider):
            item_dict = dict(item)
            cursor = self.client.cursor()
            values = ','.join(['%s'] * len(item_dict))
            keys = ','.join(item_dict.keys())
            sql = 'INSERT INTO {table}({keys}) VALUES ({values})'.format(table=self.table, keys=keys, values=values)
            try:
                if cursor.execute(sql, tuple(item_dict.values())):  # 第一个值为sql语句第二个为 值 为一个元组
                    print('数据入库成功!')
                    self.client.commit()
            except Exception as e:
                print(e)
    
                print('数据已存在!')
                self.client.rollback()
            return item
    
        def close_spider(self, spider):
    
            self.client.close()
    #定义下载
    class MyFilePipeline(FilesPipeline):
    
        def get_media_requests(self, item, info):
            for file_url in item['file_urls']:
                yield scrapy.Request(file_url,  meta = {'item': item})
    
        def file_path(self, request, response=None, info=None):
            item = request.meta['item']
            filename = u'full/{}.pdf'.format(item['title'])
            return filename
    
        def item_completed(self, results, item, info):
            image_paths = [x['path'] for ok, x in results if ok]
            if not image_paths:
                raise DropItem("Item contains no file_urls")
            item['file_urls'] = image_paths
            return item
    setting.py
    
    
    # -*- coding: utf-8 -*-
    
    # Scrapy settings for bjjs_web project
    #
    # For simplicity, this file contains only settings considered important or
    # commonly used. You can find more settings consulting the documentation:
    #
    #     https://doc.scrapy.org/en/latest/topics/settings.html
    #     https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
    #     https://doc.scrapy.org/en/latest/topics/spider-middleware.html
    
    BOT_NAME = 'bjjs_web'
    
    SPIDER_MODULES = ['bjjs_web.spiders']
    NEWSPIDER_MODULE = 'bjjs_web.spiders'
    FILES_STORE = './download'
    
    # Crawl responsibly by identifying yourself (and your website) on the user-agent
    #USER_AGENT = 'bjjs_web (+http://www.yourdomain.com)'
    
    # Obey robots.txt rules
    ROBOTSTXT_OBEY = True
    
    # mysql配置参数
    MYSQL_HOST = "172.16.10.157"
    MYSQL_PORT = 3306
    MYSQL_USER = "root"
    MYSQL_PASSWORD = "123456"
    MYSQL_DB = 'web_datas'
    TABLE = "web_bjjs"
    
    # Configure maximum concurrent requests performed by Scrapy (default: 16)
    #CONCURRENT_REQUESTS = 32
    
    # Configure a delay for requests for the same website (default: 0)
    # See https://doc.scrapy.org/en/latest/topics/settings.html#download-delay
    # See also autothrottle settings and docs
    #DOWNLOAD_DELAY = 3
    # The download delay setting will honor only one of:
    #CONCURRENT_REQUESTS_PER_DOMAIN = 16
    #CONCURRENT_REQUESTS_PER_IP = 16
    
    # Disable cookies (enabled by default)
    #COOKIES_ENABLED = False
    
    # Disable Telnet Console (enabled by default)
    #TELNETCONSOLE_ENABLED = False
    
    # 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',
    #}
    
    # Enable or disable spider middlewares
    # See https://doc.scrapy.org/en/latest/topics/spider-middleware.html
    #SPIDER_MIDDLEWARES = {
    #    'bjjs_web.middlewares.BjjsWebSpiderMiddleware': 543,
    #}
    
    # Enable or disable downloader middlewares
    # See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
    DOWNLOADER_MIDDLEWARES = {
       'bjjs_web.middlewares.BjjsWebDownloaderMiddleware': 543,
    }
    
    # Enable or disable extensions
    # See https://doc.scrapy.org/en/latest/topics/extensions.html
    #EXTENSIONS = {
    #    'scrapy.extensions.telnet.TelnetConsole': None,
    #}
    
    # Configure item pipelines
    # See https://doc.scrapy.org/en/latest/topics/item-pipeline.html
    ITEM_PIPELINES = {
        # 下载文件管道
        'scrapy.pipelines.MyFilePipeline': 1,
       'bjjs_web.pipelines.BjjsWebPipeline': 300,
    }
    
    # Enable and configure the AutoThrottle extension (disabled by default)
    # See https://doc.scrapy.org/en/latest/topics/autothrottle.html
    #AUTOTHROTTLE_ENABLED = True
    # The initial download delay
    #AUTOTHROTTLE_START_DELAY = 5
    # The maximum download delay to be set in case of high latencies
    #AUTOTHROTTLE_MAX_DELAY = 60
    # The average number of requests Scrapy should be sending in parallel to
    # each remote server
    #AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0
    # Enable showing throttling stats for every response received:
    #AUTOTHROTTLE_DEBUG = False
    
    # Enable and configure HTTP caching (disabled by default)
    # See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings
    #HTTPCACHE_ENABLED = True
    #HTTPCACHE_EXPIRATION_SECS = 0
    #HTTPCACHE_DIR = 'httpcache'
    #HTTPCACHE_IGNORE_HTTP_CODES = []
    #HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'
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  • 原文地址:https://www.cnblogs.com/lvjing/p/9842608.html
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