增量式爬虫 Scrapy-Rredis 详解及案例

增量式爬虫 Scrapy-Rredis 详解及案例[Python基础]

1、创建scrapy项目命令
scrapy startproject myproject
2、在项目中创建一个新的spider文件命令:
scrapy genspider mydomain mydomain.com              #mydomain为spider文件名,mydomain.com为爬取网站域名
3、运行项目命令
scrapy crawl <spider>
scrapy runspider <spider_file.py>                        #运行spider第二种方法
4、检查spider文件有无语法错误
scrapy check
5、其他的语法
scrapy crawl <spider> --nolog             #运行spider文件 不显示日志
scrapy list                               #列出spider路径下的spider文件
scrapy fetch <url>                        #将网页内容下载下来,然后在终端打印当前返回的内容,相当于 request 和 urllib 方法
scrapy view <url>                         #将网页内容保存下来,并在浏览器中打开当前网页内容,直观呈现要爬取网页的内容
scrapy shell [url]                        #打开 scrapy 显示台,类似ipython,可以用来做测试
scrapy parse <url> [options]              #输出格式化内容
scrapy settings [options]                 #返回系统设置信息
scrapy bench                              #测试电脑当前爬取速度性能

1、以当当网为例爬取信息如下,首先文件的结构目录如下所示
E:.
│  dangdang_content.sql
│  scrapy.cfg
│
├─.idea
│  │  misc.xml
│  │  modules.xml
│  │  ScrapyRedisPro.iml
│  │  workspace.xml
│  │
│  └─libraries
│          R_User_Library.xml
│
└─ScrapyRedisPro
    │  items.py
    │  middlewares.py
    │  pipelines.py
    │  settings.py
    │  test.py
    │  __init__.py
    │
    ├─.idea
    │  │  misc.xml
    │  │  modules.xml
    │  │  ScrapyRedisPro.iml
    │  │  workspace.xml
    │  │
    │  └─libraries
    │          R_User_Library.xml
    │
    ├─spiders
    │  │  test.py
    │  │  __init__.py
    │  │
    │  └─__pycache__
    │          test.cpython-36.pyc
    │          __init__.cpython-36.pyc
    │
    └─__pycache__
            items.cpython-36.pyc
            middlewares.cpython-36.pyc
            pipelines.cpython-36.pyc
            settings.cpython-36.pyc
            __init__.cpython-36.pyc
2、mysql数据库数据结构
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for dangdang_content
-- ----------------------------
DROP TABLE IF EXISTS `dangdang_content`;
CREATE TABLE `dangdang_content`  (
  `id` int NOT NULL AUTO_INCREMENT,
  `b_cate` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `m_cate` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `s_href` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `s_cate` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_img` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_desc` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_price` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_author` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_publish_date` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `book_press` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  `insert_data` timestamp(0) NULL DEFAULT CURRENT_TIMESTAMP(0) ON UPDATE CURRENT_TIMESTAMP(0),
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;

SET FOREIGN_KEY_CHECKS = 1;

1、spider 爬虫项目文件test.py 如下所示
# -*- coding: utf-8 -*-
import scrapy
from scrapy_redis.spiders import RedisCrawlSpider
from ScrapyRedisPro.items import ScrapyredisproItem
from copy import deepcopy
import urllib

class TestSpider(RedisCrawlSpider):
    name = "test"
    # allowed_domains = ["www.baidu.com"]
    # start_urls = ["http://www.baidu.com/"]

    #调度器队列名称
    redis_key = "dangdang"

    def parse(self, response):
        """
        逻辑分析
            1.通过抓取下一页的链接,交给scrapy实现自动翻页,如果没有下一页则爬取完成
            2.将本页面的所有文章url爬下,并交给scrapy进行深入详情页的爬取
        """

        # 大分类分组
        div_list = response.xpath("//div[@class="con flq_body"]/div")
        for div in div_list:
            item = {}
            item["b_cate"] = div.xpath("./dl/dt//text()").extract()
            item["b_cate"] = [i.strip() for i in item["b_cate"] if len(i.strip()) > 0]
            # 中间分类分组
            dl_list = div.xpath("./div//dl[@class="inner_dl"]")
            for dl in dl_list:
                item["m_cate"] = dl.xpath("./dt//text()").extract()
                item["m_cate"] = [i.strip() for i in item["m_cate"] if len(i.strip()) > 0][0]
                # 小分类分组
                a_list = dl.xpath("./dd/a")
                for a in a_list:
                    item["s_href"] = a.xpath("./@href").extract_first()
                    item["s_cate"] = a.xpath("./text()").extract_first()
                    if item["s_href"] is not None:
                        # print(item)
                        yield scrapy.Request(
                            item["s_href"],
                            callback=self.parse_book_list,
                            meta={"item": deepcopy(item)}
                        )

    def parse_book_list(self, response):
        """
            将爬虫爬取的数据送到item中进行序列化
            这里通过ItemLoader加载item
        """
        item = response.meta["item"]
        li_list = response.xpath("//ul[@class="bigimg"]/li")
        for li in li_list:
            item["book_img"] = li.xpath("./a[@class="pic"]/img/@src").extract_first()
            if item["book_img"] == "images/model/guan/url_none.png":
                item["book_img"] = li.xpath("./a[@class="pic"]/img/@data-original").extract_first()
            item["book_name"] = li.xpath("./p[@class="name"]/a/@title").extract_first()
            item["book_desc"] = li.xpath("./p[@class="detail"]/text()").extract_first()
            item["book_price"] = li.xpath(".//span[@class="search_now_price"]/text()").extract_first()
            item["book_author"] = li.xpath("./p[@class="search_book_author"]/span[1]/a/text()").extract()
            item["book_publish_date"] = li.xpath("./p[@class="search_book_author"]/span[2]/text()").extract_first()
            item["book_press"] = li.xpath("./p[@class="search_book_author"]/span[3]/a/text()").extract_first()
            # print(item)
            yield item
        # 下一页
        next_url = response.xpath("//li[@class="next"]/a/@href").extract_first()
        if next_url is not None:
            next_url = urllib.parse.urljoin(response.url, next_url)
            yield scrapy.Request(
                next_url,
                callback=self.parse_book_list,
                meta={"item": item}
            )
Middlewware.py 中间件文件
# -*- 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

from scrapy.http import HtmlResponse
import time
from scrapy.downloadermiddlewares.useragent import UserAgentMiddleware
import random


class ScrapyredisproSpiderMiddleware(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 ScrapyredisproDownloaderMiddleware(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

    # 拦截到响应对象(下载器传递给Spider的响应对象)
    # request:响应对象对应的请求对象
    # response:拦截到的响应对象
    # spider:爬虫文件中对应的爬虫类的实例
    def process_response(self, request, response, spider):
        # 响应对象中存储页面数据的篡改
        if request.url in ["http://news.163.com/domestic/", "http://news.163.com/world/", "http://news.163.com/air/",
                           "http://war.163.com/"]:
            spider.bro.get(url=request.url)
            js = "window.scrollTo(0,document.body.scrollHeight)"
            spider.bro.execute_script(js)
            time.sleep(3)  # 一定要给与浏览器一定的缓冲加载数据的时间
            # 页面数据就是包含了动态加载出来的新闻数据对应的页面数据
            page_text = spider.bro.page_source
            # 篡改响应对象
            return HtmlResponse(url=spider.bro.current_url, body=page_text, encoding="utf-8", request=request)
        else:
            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)


#UA池代码的编写(单独给UA池封装一个下载中间件的一个类)
#1,导包UserAgentMiddlware类
class RandomUserAgent(UserAgentMiddleware):

    def process_request(self, request, spider):
        #从列表中随机抽选出一个ua值
        ua = random.choice(user_agent_list)
        #ua值进行当前拦截到请求的ua的写入操作
        request.headers.setdefault("User-Agent",ua)

#批量对拦截到的请求进行ip更换
class Proxy(object):
    def process_request(self, request, spider):
        #对拦截到请求的url进行判断(协议头到底是http还是https)
        #request.url返回值:http://www.xxx.com
        h = request.url.split(":")[0]  #请求的协议头
        if h == "https":
            ip = random.choice(PROXY_https)
            request.meta["proxy"] = "https://"+ip
        else:
            ip = random.choice(PROXY_http)
            request.meta["proxy"] = "http://" + ip


PROXY_http = [
    "153.180.102.104:80",
    "195.208.131.189:56055",
]
PROXY_https = [
    "120.83.49.90:9000",
    "95.189.112.214:35508",
]

user_agent_list = [
        "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 "
        "(KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1",
        "Mozilla/5.0 (X11; CrOS i686 2268.111.0) AppleWebKit/536.11 "
        "(KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
        "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.6 "
        "(KHTML, like Gecko) Chrome/20.0.1092.0 Safari/536.6",
        "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.6 "
        "(KHTML, like Gecko) Chrome/20.0.1090.0 Safari/536.6",
        "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.1 "
        "(KHTML, like Gecko) Chrome/19.77.34.5 Safari/537.1",
        "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.5 "
        "(KHTML, like Gecko) Chrome/19.0.1084.9 Safari/536.5",
        "Mozilla/5.0 (Windows NT 6.0) AppleWebKit/536.5 "
        "(KHTML, like Gecko) Chrome/19.0.1084.36 Safari/536.5",
        "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
        "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
        "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_0) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
        "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
        "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
        "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
        "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
        "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
        "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
        "(KHTML, like Gecko) Chrome/19.0.1061.0 Safari/536.3",
        "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.24 "
        "(KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24",
        "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/535.24 "
        "(KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24"
]
3、items.py 文件
# -*- 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 ScrapyredisproItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    b_cate = scrapy.Field()
    m_cate = scrapy.Field()
    s_href = scrapy.Field()
    s_cate = scrapy.Field()
    book_img = scrapy.Field()
    book_name = scrapy.Field()
    book_desc = scrapy.Field()
    book_price = scrapy.Field()
    book_author = scrapy.Field()
    book_publish_date = scrapy.Field()
    book_press = scrapy.Field()

4、pipelines.py 管道文件

注意 一般下载方式有两种,异步与同步下载方式(下列两种方式都有)

# -*- 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
import pymysql.cursors
from twisted.enterprise import adbapi

class ScrapyredisproPipeline(object):
#     def process_item(self, item, spider):
#         return item
# class MysqlTwistedPipeline(object):
    """
        异步机制将数据写入到mysql数据库中
    """

    # 创建初始化函数,当通过此类创建对象时首先被调用的方法
    def __init__(self, dbpool):
        self.dbpool = dbpool

    # 创建一个静态方法,静态方法的加载内存优先级高于init方法,
    # 在创建这个类的对之前就已将加载到了内存中,所以init这个方法可以调用这个方法产生的对象
    @classmethod
    # 名称固定的
    def from_settings(cls, settings):
        # 先将setting中连接数据库所需内容取出,构造一个地点
        dbparms = dict(
            host=settings["MYSQL_HOST"],
            port=settings["MYSQL_PORT"],
            db=settings["MYSQL_DBNAME"],
            user=settings["MYSQL_USER"],
            password=settings["MYSQL_PASSWORD"],
            charset="utf8",
            # 游标设置
            cursorclass=pymysql.cursors.DictCursor,
            # 设置编码是否使用Unicode
            use_unicode=True
        )
        # 通过Twisted框架提供的容器连接数据库,pymysql是数据库模块名
        dbpool = adbapi.ConnectionPool("pymysql",**dbparms)
        print("连接成功!")
        # 无需直接导入 dbmodule. 只需要告诉 adbapi.ConnectionPool 构造器你用的数据库模块的名称比如pymysql.
        return cls(dbpool)

    def process_item(self, item, spider):
        # 使用Twisted异步的将Item数据插入数据库
        query = self.dbpool.runInteraction(self.do_insert, item)
        query.addErrback(self.handle_error, item, spider)  # 这里不往下传入item,spider,handle_error则不需接受,item,spider)

    def do_insert(self, cursor, item):
        # 执行具体的插入语句,不需要commit操作,Twisted会自动进行
        insert_sql = """
                 insert into dangdang_content(b_cate, m_cate, s_href, s_cate, book_img, book_name, book_desc, book_price, book_author, book_publish_date, book_press) VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)
            """
        cursor.execute(insert_sql, (item["b_cate"][0], item["m_cate"], item["book_img"], item["s_href"], item["s_cate"], item["book_name"], item["book_desc"], item["book_price"], item["book_author"][0], item["book_publish_date"], item["book_press"]))
        
        print("------------------------------数据插入成功!")
    def handle_error(self, failure, item, spider):
        # 异步插入异常
        if failure:
            print(failure)



# class MysqlTwistedPipeline(object):
    # """
    #     同步步机制将数据写入到mysql数据库中
    # """
    # 
    # # 创建初始化函数,当通过此类创建对象时首先被调用的方法
    # def __init__(self, conn, cursor):
    #     self.conn = conn
    #     self.cursor = cursor
    # 
    # # 创建一个静态方法,静态方法的加载内存优先级高于init方法,
    # # 在创建这个类的对之前就已将加载到了内存中,所以init这个方法可以调用这个方法产生的对象
    # @classmethod
    # # 名称固定的
    # def from_settings(cls, settings):
    #     # 先将setting中连接数据库所需内容取出,构造一个地点
    #     dbparms = dict(
    #         host=settings["MYSQL_HOST"],
    #         port=settings["MYSQL_PORT"],
    #         db=settings["MYSQL_DBNAME"],
    #         user=settings["MYSQL_USER"],
    #         password=settings["MYSQL_PASSWORD"],
    #         charset="utf8",
    #         # 游标设置
    #         cursorclass=pymysql.cursors.DictCursor,
    #         # 设置编码是否使用Unicode
    #         use_unicode=True
    #     )
    #     conn = pymysql.connect(**dbparms)
    #     cursor = conn.cursor()
    #     # 无需直接导入 dbmodule. 只需要告诉 adbapi.ConnectionPool 构造器你用的数据库模块的名称比如pymysql.
    #     return cls(conn, cursor)
    # 
    # def process_item(self, item, spider):
    #     insert_sql = "insert into dangdang_content(b_cate[0], m_cate, s_href, s_cate, book_img, book_name, book_desc, book_price, book_author, book_publish_date, book_press) VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)".format(item["b_cate"], item["m_cate"], item["book_img"], item["s_href"], item["s_cate"], item["book_name"], item["book_desc"], item["book_price"], item["book_author"][0], item["book_publish_date"], item["book_press"])
    #     print(insert_sql)
    #     self.cursor.execute(insert_sql)
    #     self.conn.commit()
    #     print("------------------------------数据插入成功!")
    # 
    # def handle_error(self, failure, item, spider):
    #     # 异步插入异常
    #     if failure:
    #         print(failure)
    # 
    # def close_spider(self, spider):
    #     """
    #     清理
    #     :param spider:
    #     :return:
    #     """
    #     self.cursor.close()
    #     self.conn.close()
5、settings.py 配置文件
# -*- coding: utf-8 -*-

# Scrapy settings for ScrapyRedisPro 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 = "ScrapyRedisPro"

SPIDER_MODULES = ["ScrapyRedisPro.spiders"]
NEWSPIDER_MODULE = "ScrapyRedisPro.spiders"


# Crawl responsibly by identifying yourself (and your website) on the user-agent
#USER_AGENT = "ScrapyRedisPro (+http://www.yourdomain.com)"
USER_AGENT = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36"  # 伪装请求载体身份
# Obey robots.txt rules
ROBOTSTXT_OBEY = False  #可以忽略或者不遵守robots协议
#只显示指定类型的日志信息
LOG_LEVEL="ERROR"

# 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 = {
#    "ScrapyRedisPro.middlewares.ScrapyredisproSpiderMiddleware": 543,
#}

# Enable or disable downloader middlewares
# See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
DOWNLOADER_MIDDLEWARES = {
   "ScrapyRedisPro.middlewares.ScrapyredisproDownloaderMiddleware": 543,
   "ScrapyRedisPro.middlewares.RandomUserAgent": 542,
}

# 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 = {
   "ScrapyRedisPro.pipelines.ScrapyredisproPipeline": 300,
   "scrapy_redis.pipelines.RedisPipeline": 400 ,
   # "ScrapyRedisPro.pipelines.MysqlTwistedPipeline": 301,
}

# 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"


""" scrapy-redis配置 """
# Enables scheduling storing requests queue in redis.
# 使用scrapy-redis组件自己的调度器
SCHEDULER = "scrapy_redis.scheduler.Scheduler"
# 增加了一个去重容器类的配置, 作用使用Redis的set集合来存储请求的指纹数据, 从而实现请求去重的持久化
# Ensure all spiders share same duplicates filter through redis.
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"
# 配置调度器是否要持久化, 也就是当爬虫结束了, 要不要清空Redis中请求队列和去重指纹的set。如果是True, 就表示要持久化存储, 就不清空数据, 否则清空数据
SCHEDULER_PERSIST = True                       # 为false Redis关闭了 Redis数据也会被清空

# redis的配置
REDIS_HOST = "127.0.0.1"
REDIS_PORT = 6379
REDIS_ENCODING ="utf8"
REDIS_PARAMS = {"password":"xhw123"}

MYSQL_HOST = "127.0.0.1"
MYSQL_PORT = 3306
MYSQL_DBNAME = "spidertest"
MYSQL_USER = "root"
MYSQL_PASSWORD = "xhw123"


# 增加了一个去重容器类的配置, 作用使用Redis的set集合来存储请求的指纹数据, 从而实现请求去重的持久化
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"
# 使用scrapy-redis组件自己的调度器
SCHEDULER = "scrapy_redis.scheduler.Scheduler"
# 配置调度器是否要持久化, 也就是当爬虫结束了, 要不要清空Redis中请求队列和去重指纹的set。如果是True, 就表示要持久化存储, 就不清空数据, 否则清空数据
SCHEDULER_PERSIST = True

注意 启动项目后需要在redis的客户端执行如下命令

127.0.0.1:6379> lpush dangdang http://book.dangdang.com/
hmoban主题是根据ripro二开的主题,极致后台体验,无插件,集成会员系统
自学咖网 » 增量式爬虫 Scrapy-Rredis 详解及案例