第四次作业

作业一

（1）熟练掌握 scrapy 中 Item、Pipeline 数据的序列化输出方法；Scrapy+Xpath+MySQL数据库存储技术路线爬取当当网站图书数据

候选网站：http://www.dangdang.com/

graph TD A[解析当当网址] -->|print| B(先看一下有木有爬下来) B --> C{xpath获取需要的item} C -->|和mysql建立连接| D[试往里存] C -->|都OK| F[run]

#！/usr/bin/env python
# _*_ coding:utf-8 _*_
# author: xm time:2020/10/27
import scrapy
from ..items import DangdangItem
from bs4 import BeautifulSoup
from bs4 import UnicodeDammit

class spider_dangdang(scrapy.Spider):
    name = "spiderdangdang"
    # key = 'python'
    # source_url='http://www.dangdang.com/'
    # start_urls=["http://search.dangdang.com/?key=python&act=input&page_index=2"]
    def start_requests(self):
        url="http://search.dangdang.com/?key=python&act=input"
        print(url)
        yield scrapy.Request(url=url,callback=self.parse)

    def parse(self, response):
        try:
            dammit = UnicodeDammit(response.body,["utf-8",'gbk'])
            data = dammit.unicode_markup
            selector=scrapy.Selector(text=data)
            lis = selector.xpath("//ul[@class='bigimg']/li")
            for li in lis:
                title = li.xpath("./p[@class='name']/a/@title").extract_first()
                author = li.xpath("./p[@class='search_book_author']/span[position()=1]/a/@title").extract_first()
                price = li.xpath("./p[@class='price']/span[@class='search_now_price']/text()").extract_first()
                date = li.xpath("./p[@class='search_book_author']/span[position()=last()-1]/text()").extract_first()
                publisher = li.xpath("./p[@class='search_book_author']/span[position()=3]/a/@title").extract_first()
                detail = li.xpath("./p[@class='detail']/text()").extract_first()
                # print(title)
                item=DangdangItem()
                item["title"]=title.strip() if title else ""
                item["author"]=author.strip() if author else ""
                item['price']=price.strip() if price else ""
                item['date']=date.strip()[1:] if price else ""
                item['publisher']=publisher.strip() if publisher else ""
                item['detail']=detail.strip() if detail else ""
                yield item
        except Exception as err:
            print(err)

import scrapy
class DangdangItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    title = scrapy.Field()
    author = scrapy.Field()
    publisher = scrapy.Field()
    date = scrapy.Field()
    price = scrapy.Field()
    detail = scrapy.Field()

import pymysql
class DangdangPipeline:
    def open_spider(self,spider):
        print("opened")
        try:
            self.con=pymysql.connect(host="127.0.0.1",port=3306,user="root",
                                     passwd="031804114.hao",db="mydb",charset="utf8")
            self.cursor=self.con.cursor(pymysql.cursors.DictCursor)
            self.cursor.execute("delete from books")
            self.opened=True
            self.count=0
        except Exception as err:
            print(err)
            self.opened=False
    def close_spider(self,spider):
        if self.opened:
            self.con.commit()
            self.con.close()
            self.opened=False
        print("closed")
        print("总共爬取",self.count,"本书籍")
    def process_item(self, item, spider):
        try:
            if self.opened:
                self.cursor.execute("insert into books(bTitle,bAuthor,bPublisher,bDate,bPrice,bDetail) values (%s,%s,%s,%s,%s,%s)",(item["title"],item["author"],item["publisher"],item["date"],item["price"],item["detail"]))
                self.count+=1
        except Exception as err:
            print(err)
        return item

（2）心得体会

Xpath的解析标签要详细一点，还有python3的去除字符的空格，str.strip()去除两端的空格；mysql记得创建表的时候加一句 character set = utf8，默认的不是utf8，不然就给你存的时候搞事情

作业二

（1）熟练掌握 scrapy 中 Item、Pipeline 数据的序列化输出方法；Scrapy+Xpath+MySQL数据库存储技术路线爬取股票相关信息

东方财富网：https://www.eastmoney.com/ 新浪股票：http://finance.sina.com.cn/stock/

#！/usr/bin/env python
# _*_ coding:utf-8 _*_
# author: xm time:2020/10/28
import scrapy
import json
import re
import math
from ..items import GupiaomysqlItem
class spider_gupiao(scrapy.Spider):
    name = "spidergupiao"
    start_urls=["http://11.push2.eastmoney.com/api/qt/clist/get?&pn=1&pz=20&po=1&np=1&ut=bd1d9ddb04089700cf9c27f6f7426281&fltt=2&invt=2&fid=f3&fs=m:0+t:6,m:0+t:13,m:0+t:80,m:1+t:2,m:1+t:23&fields=f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f12,f13,f14,f15,f16,f17,f18,f20,f21,f23,f24,f25,f22,f11,f62,f128,f136,f115,f152&_=1603874731034"]
    def parse(self, response):
        try:
            sites = json.loads(response.body_as_unicode())
            data = sites["data"]
            diff = data["diff"]
            print(diff)
            print(len(diff))
            for i in range(len(diff)):
                item=GupiaomysqlItem()
                item["mount"]=str(i)
                item["code"]=str(diff[i]["f12"])
                item["name"]=str(diff[i]["f14"])
                item["lately"]=str(diff[i]["f2"])
                item["zhangdiefu"]=str(diff[i]["f3"])
                item["zhangdiee"]=str(diff[i]["f4"])
                item["chengjiaoliang"]=str(diff[i]["f5"])
                item["chengjiaoe"]=str(diff[i]["f6"])
                item["zhenfu"]=str(diff[i]["f7"])
                item["zuigao"]=str(diff[i]["f15"])
                item["zuidi"]=str(diff[i]["f16"])
                item["jinkai"]=str(diff[i]["f17"])
                item["zuoshou"]=str(diff[i]["f18"])
                yield item
            #all_page = math.ceil(eval(re.findall('"total":(d+)', response.body.decode())[0]) / 20)
            page = re.findall("pn=(d+)", response.url)[0]  # 当前页数
            if int(page) < 5:  # 爬取页数
                url = response.url.replace("pn=" + page, "pn=" + str(int(page) + 1))  # 跳转下一页
                yield scrapy.Request(url=url, callback=self.parse)
            yield scrapy.Request(url, self.parse)
        except Exception as err:
                    print(err)

import scrapy
class GupiaomysqlItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    mount = scrapy.Field()
    code = scrapy.Field()
    name = scrapy.Field()
    lately = scrapy.Field()
    zhangdiefu = scrapy.Field()
    zhangdiee = scrapy.Field()
    chengjiaoliang = scrapy.Field()
    chengjiaoe = scrapy.Field()
    zhenfu = scrapy.Field()
    zuigao = scrapy.Field()
    zuidi = scrapy.Field()
    jinkai = scrapy.Field()
    zuoshou = scrapy.Field()

from itemadapter import ItemAdapter
import pymysql
class GupiaomysqlPipeline:
    def open_spider(self,spider):
        print("opened")
        try:
            self.con=pymysql.connect(host="127.0.0.1",port=3306,user="root",
                                     passwd="031804114.hao",db="gupiao",charset="utf8")
            self.cursor=self.con.cursor(pymysql.cursors.DictCursor)
            self.cursor.execute("delete from information")
            self.opened=True
            self.count=0
        except Exception as err:
            print(err)
            self.opened=False
    def close_spider(self,spider):
        if self.opened:
            self.con.commit()
            self.con.close()
            self.opened=False
        print("closed")
        print("总共爬取",self.count,"条")
    def process_item(self, item, spider):
        try:
            print(item["mount"])
            print()
            if self.opened:
                self.cursor.execute("insert into information(id,bno,bname,bLatestPrice,bZhangDieFu,bZhangDieE,bChengJiaoLiang,bChengJioaE,bZhenFu,bZuiGao,bZuiDi,bJinKai,bZuoShou) values (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)",(item["mount"],item["code"],item["name"],item["lately"],item["zhangdiefu"],item["zhangdiee"],item["chengjiaoliang"],item["chengjiaoe"],item["zhenfu"],item["zuigao"],item["zuidi"],item["jinkai"],item["zuoshou"]))
                self.count+=1
        except Exception as err:
            print(err)
        return item

（2）心得体会

主要还是根据上次爬股票的小爬5页，数据库的操作和实验一一样

作业三

（1）熟练掌握 scrapy 中 Item、Pipeline 数据的序列化输出方法；使用scrapy框架+Xpath+MySQL数据库存储技术路线爬取外汇网站数据。

招商银行网：http://fx.cmbchina.com/hq/

#！/usr/bin/env python
# _*_ coding:utf-8 _*_
# author: xm time:2020/10/30
import scrapy
from bs4 import UnicodeDammit
from ..items import WaihuimysqlItem
class spider_waihui(scrapy.Spider):
    name = "spiderwaihui"
    start_urls=["http://fx.cmbchina.com/hq/"]
    def parse(self, response):
        try:
            dammit = UnicodeDammit(response.body, ["utf-8", 'gbk'])
            data = dammit.unicode_markup
            # print(data)
            selector = scrapy.Selector(text=data)
            trs = selector.xpath("//div[@id='realRateInfo']/table/tr")
            # print(trs)
            for tr in trs[1:]:
                item=WaihuimysqlItem()
                a =tr.xpath("./td[position()=1][@class='fontbold']/text()").extract_first()
                item["type"] = str(a).strip()
                item["tsp"] = str(tr.xpath("./td[position()=4][@class='numberright']/text()").extract_first()).strip()
                item["csp"] = str(tr.xpath("./td[position()=5][@class='numberright']/text()").extract_first()).strip()
                item["tbp"] = str(tr.xpath("./td[position()=6][@class='numberright']/text()").extract_first()).strip()
                item["cbp"] = str(tr.xpath("./td[position()=7][@class='numberright']/text()").extract_first()).strip()
                item["time"] = str(tr.xpath("./td[position()=8][@align='center']/text()").extract_first()).strip()
                yield item
        except Exception as err:
            print(err)

import scrapy
class WaihuimysqlItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    type = scrapy.Field()
    tsp = scrapy.Field()
    csp = scrapy.Field()
    tbp = scrapy.Field()
    cbp = scrapy.Field()
    time = scrapy.Field()

import pymysql
class WaihuimysqlPipeline:
    def open_spider(self,spider):
        print("opened")
        try:
            self.con=pymysql.connect(host="127.0.0.1",port=3306,user="root",
                                     passwd="031804114.hao",db="mydb",charset="utf8")
            self.cursor=self.con.cursor(pymysql.cursors.DictCursor)
            self.cursor.execute("delete from waihui")
            self.opened=True
            self.count=0
        except Exception as err:
            print(err)
            self.opened=False
    def close_spider(self,spider):
        if self.opened:
            self.con.commit()
            self.con.close()
            self.opened=False
        print("closed")
        print("总共爬取",self.count,"条")
    def process_item(self, item, spider):
        try:
            if self.opened:
                self.cursor.execute("insert into waihui(btype,btsp,bcsp,btbp,bcbp,btime) values (%s,%s,%s,%s,%s,%s)",(item["type"],item["tsp"],item["csp"],item["tbp"],item["cbp"],item["time"]))
                self.count+=1
        except Exception as err:
            print(err)
        return item

（2）心得体会

有上面两个实验这个很简单，就是去除空格就好了

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原文地址：https://www.cnblogs.com/lmmlm/p/13907495.html