BZ易风

导航

 

安装

pip install scrapy

建立一个爬虫项目

scrapy startproject 项目名称

scrapy startproject itcast

进入itcast文件夹 生成一个爬虫

scrapy genspider 爬虫名称 "爬虫范围"

scrapy genspider itcast "itcast.cn"

爬虫生成位置

 

 

 编写itcast.py

# -*- coding: utf-8 -*-
import scrapy


class ItcastSpider(scrapy.Spider):
    name = "itcast"
    allowed_domains = ["itcast.cn"]
    start_urls = (
        'http://www.itcast.cn/channel/teacher.shtml',
    )

    def parse(self, response):
        # print(response)
        data_list = response.xpath("//div[@class='tea_con']//h3/text()").extract()  # extract() 返回一个含有字符串数据的列表 如果没用这个方法 返回一个包含选择器的列表
        print(data_list)  # 乱码 u\u5218.... setting.py中添加了 FEED_EXPORT_ENCODING = 'utf-8' 还是不行 不知道原因  ???
        for i in data_list:
            print(i)  # 此处打印的是中文 

乱码是由于ubuntu终端没有中文安装包

安装中文包

apt-get install language-pack-zh

修改 /tec/environment

sudo gedit /etc/environment

在下面添加两行

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games"
LANG="zh_CN.UTF-8"
LANGUAGE="zh_CN:zh:en_US:en"

第二行即是默认的中文字符编码。注:可以通过这里修改默认的中文编 码字符,比如修改为:zh_CN.GBK

修改/var/lib/locales/supported.d/local文件

sudo gedit /var/lib/locales/supported.d/local

添加

zh_CN.UTF-8 UTF-8
en_US.UTF-8 UTF-8

保存后,执行命令

sudo locale-gen

重启

sudo reboot

解决 乱码没有了,可以显示中文了

终端打印出来后有其它数据

setting.py中配置log的等级

LOG_LEVEL = "WARNING"

 xapath分组 数据传到pipline itcast.py中

# -*- coding: utf-8 -*-
import scrapy


class ItcastSpider(scrapy.Spider):
    name = "itcast"
    allowed_domains = ["itcast.cn"]
    start_urls = (
        'http://www.itcast.cn/channel/teacher.shtml',
    )

    def parse(self, response):
        # # print(response)
        # data_list = response.xpath("//div[@class='tea_con']//h3/text()").extract()  # extract() 返回一个含有字符串数据的列表 如果没用这个方法 返回一个包含选择器的列表
        # print(data_list)  # 乱码 u\u5218.... setting.py中添加了 FEED_EXPORT_ENCODING = 'utf-8' 还是不行 不知道原因  ???
        # for i in data_list:
        #     print(i)  # 此处打印的是中文
        ret = response.xpath("//div[@class='tea_con']//li")  # xpath分组提取
        # print(ret)
        for i in ret:
            item = {}
            item['name'] = i.xpath(".//h3/text()").extract_first()  # extract_first()相当于 extract()[0] 取列表的第一条数据 
            # extrack_first() 如果没有数据则返回空列表
            # extrack()[0] 如果没有数据会报错
            item['position'] = i.xpath(".//h4/text()").extract_first()
            item['commondcommond'] = i.xpath(".//p/text()").extract_first()
            yield item  # 把数据传给pipline

pipline如果想显示接收数据 先要在设置setting.py中开启

# -*- coding:utf-8 -*-

# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: http://doc.scrapy.org/en/latest/topics/item-pipeline.html
import json
import codecs

class MyspiderPipeline(object):
    # def __init__(self):
    #     # 定义文件编码及名称
    #     self.file = codecs.open('中文乱码.json', 'wb', encoding='utf-8')

    def process_item(self, item, spider):  # 实现存储方法
        # line = json.dumps(dict(item)) + '\n'
        # print(line.decode("unicode_escape"))
        # 写入一行,每行为一个抓取项
        # self.file.write(line.decode("unicode_escape"))
        # return item
        print(item)
     return item

 查看效果,控制端输入代码

scrapy crawl itcast

 

 使用多个pipline

# -*- coding:utf-8 -*-

# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: http://doc.scrapy.org/en/latest/topics/item-pipeline.html
import json
import codecs

class MyspiderPipeline(object):
    # def __init__(self):
    #     # 定义文件编码及名称
    #     self.file = codecs.open('中文乱码.json', 'wb', encoding='utf-8')

    def process_item(self, item, spider):
        # line = json.dumps(dict(item)) + '\n'
        # print(line.decode("unicode_escape"))
        # 写入一行,每行为一个抓取项
        # self.file.write(line.decode("unicode_escape"))
        # return item
        del item["commondcommond"]  # 删除详细介绍
        return item

class MyspiderPipeline2(object):
    def process_item(self, item, spider):
        print(item)  # 此时item是从上面方法处理后的item
        return item

配置setting.py

# Configure item pipelines
# See http://scrapy.readthedocs.org/en/latest/topics/item-pipeline.html
ITEM_PIPELINES = {
   'myspider.pipelines.MyspiderPipeline': 300,
   'myspider.pipelines.MyspiderPipeline2': 301,
}

查看效果

 

 

创建多个爬虫

一个爬虫项目是包含多个爬虫的  

scrapy genspider itcast2 itcast.cn
scrapy genspider itcast3 itcast.cn

 

 

 

 关于多个爬虫的pipline处理方式:

爬虫itcast.py返回值里添加comfrom

  def parse(self, response):
        # # print(response)
        # data_list = response.xpath("//div[@class='tea_con']//h3/text()").extract()  # extract() 返回一个含有字符串数据的列表 如果没用这个方法 返回一个包含选择器的列表
        # print(data_list)  # 乱码 u\u5218.... setting.py中添加了 FEED_EXPORT_ENCODING = 'utf-8' 还是不行 不知道原因  ???
        # for i in data_list:
        #     print(i)  # 此处打印的是中文
        ret = response.xpath("//div[@class='tea_con']//li")  # xpath分组提取
        # print(ret)
        for i in ret:
            item = {}
            item['comfrom'] = 'itcast'  # 便于pipline区分
            item['name'] = i.xpath(".//h3/text()").extract_first()  # extract_first()相当于 extract()[0] 取列表的第一条数据
            # extrack_first() 如果没有数据则返回空列表
            # extrack()[0] 如果没有数据会报错
            item['position'] = i.xpath(".//h4/text()").extract_first()
            item['commond'] = i.xpath(".//p/text()").extract_first()
            yield item  # 把数据传给pipline

1.多个爬虫使用一个pipline 

piplind处理方法

class MyspiderPipeline(object):
    def process_item(self, item, spider):
        
        if item['comfrom'] == 'itcast':
            pass  # itcast的处理方式
        elif item['comfrom'] == 'itcast2':
            pass  # itcast2 的处理方式
        else:
            pass  # itcast3 的处理方式

2.多个爬虫使用多个pipline区分

class MyspiderPipeline(object):
    def process_item(self, item, spider):

        if item['comfrom'] == 'itcast':
            pass  # itcast的处理方式

class MyspiderPipeline2(object):
    def process_item(self, item, spider):

        if item['comfrom'] == 'itcast2':
            pass  # itcast2 的处理方式

class MyspiderPipeline3(object):
    def process_item(self, item, spider):
        if item['comfrom'] == 'itcast3':
            pass  # itcast3 的处理方式

配置seting.py里注册pipline2、pipline3的权重

ITEM_PIPELINES = {
   'myspider.pipelines.MyspiderPipeline': 300,
   'myspider.pipelines.MyspiderPipeline2': 301,
   'myspider.pipelines.MyspiderPipeline3': 302,
}

3.根据spider.name区分

# -*- coding: utf-8 -*-
import scrapy


class ItcastSpider(scrapy.Spider):
    name = "itcast"  # 类属性name 便于piplinde区分
    allowed_domains = ["itcast.cn"]
    start_urls = (
        'http://www.itcast.cn/channel/teacher.shtml',
    )

    def parse(self, response):
        # # print(response)
        # data_list = response.xpath("//div[@class='tea_con']//h3/text()").extract()  # extract() 返回一个含有字符串数据的列表 如果没用这个方法 返回一个包含选择器的列表
        # print(data_list)  # 乱码 u\u5218.... setting.py中添加了 FEED_EXPORT_ENCODING = 'utf-8' 还是不行 不知道原因  ???
        # for i in data_list:
        #     print(i)  # 此处打印的是中文
        ret = response.xpath("//div[@class='tea_con']//li")  # xpath分组提取
        # print(ret)
        for i in ret:
            item = {}
            item['comfrom'] = 'itcast'
            item['name'] = i.xpath(".//h3/text()").extract_first()  # extract_first()相当于 extract()[0] 取列表的第一条数据
            # extrack_first() 如果没有数据则返回空列表
            # extrack()[0] 如果没有数据会报错
            item['position'] = i.xpath(".//h4/text()").extract_first()
            item['commond'] = i.xpath(".//p/text()").extract_first()
            yield item  # 把数据传给pipline

pipline中

class MyspiderPipeline(object):
    def process_item(self, item, spider):

        if spider.name == 'itcast':
            pass  # 当spider的类属性name是itcast时的处理方式

 使用loggin日志

开启日志输出到文件配置sitting.py

LOG_LEVEL = "WARNING"  # 日志级别
LOG_FILE = "./log.log"  # 把日志保存到文件, 文件保存位置

 itcast.py或者pipline中

# -*- coding: utf-8 -*-
import scrapy
import logging

logger = logging.getLogger(__name__)  # 获取logger对象 可以以spider名称存入log日志

class ItcastSpider(scrapy.Spider):
    name = "itcast"
    allowed_domains = ["itcast.cn"]
    start_urls = (
        'http://www.itcast.cn/channel/teacher.shtml',
    )

    def parse(self, response):
        # # print(response)
        # data_list = response.xpath("//div[@class='tea_con']//h3/text()").extract()  # extract() 返回一个含有字符串数据的列表 如果没用这个方法 返回一个包含选择器的列表
        # print(data_list)  # 乱码 u\u5218.... setting.py中添加了 FEED_EXPORT_ENCODING = 'utf-8' 还是不行 不知道原因  ???
        # for i in data_list:
        #     print(i)  # 此处打印的是中文
        ret = response.xpath("//div[@class='tea_con']//li")  # xpath分组提取
        # print(ret)
        for i in ret:
            item = {}
            item['comfrom'] = 'itcast'
            item['name'] = i.xpath(".//h3/text()").extract_first()  # extract_first()相当于 extract()[0] 取列表的第一条数据
            # extrack_first() 如果没有数据则返回空列表
            # extrack()[0] 如果没有数据会报错
            item['position'] = i.xpath(".//h4/text()").extract_first()
            item['commond'] = i.xpath(".//p/text()").extract_first()
            logger.warning(item)  # 对应setting配置的LOG_LEVEL级别,把日志输出到日志文件
            yield item  # 把数据传给pipline

 实现翻页请求

 

 

实例

 # 获取总页数
        pageNum=math.ceil(data_lists['Data']['Count']/10)
        # 设置第二页页码
        pageIndex = 2
        while pageIndex<=pageNum:
            next_url = "https://careers.tencent.com/tencentcareer/api/post/Query?pageIndex={}&pageSize=10".format(pageIndex)
            yield scrapy.Request(
                next_url,
                callback=self.parse
            )
            pageIndex += 1

meta用途

 def parse(self, response):
        data_lists = json.loads(response.text)
        data_list = data_lists['Data']['Posts']
        for data in data_list:
            item = {}
            item['RecruitPostName'] = data['RecruitPostName']
            item['CountryName'] = data['CountryName']
            item['PostURL'] = data['PostURL']
            item['LastUpdateTime'] = data['LastUpdateTime']
            print(item)

        # 获取总页数
        pageNum=math.ceil(data_lists['Data']['Count']/10)
        # 设置第二页页码
        pageIndex = 2
        while pageIndex<=pageNum:
            next_url = "https://careers.tencent.com/tencentcareer/api/post/Query?pageIndex={}&pageSize=10".format(pageIndex)
            yield scrapy.Request(
                next_url,
                callback=self.parse,
                meta={"item":item}  # meta用法 在不同的解析函数中传递数据
            )
            pageIndex += 1

    def parse1(self, response):
        item = response.meta["item"]

 Scrapy深入之定义Item

可以在items.py中把要爬取的字段定义好

# -*- coding: utf-8 -*-

# Define here the models for your scraped items
#
# See documentation in:
# http://doc.scrapy.org/en/latest/topics/items.html

import scrapy


class HrItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    RecruitPostName = scrapy.Field()
    CountryName = scrapy.Field()
    PostURL = scrapy.Field()
    LastUpdateTime = scrapy.Field()

此时要把爬虫tencent.py中关于item字典改动一下

# -*- coding: utf-8 -*-
import scrapy
import json
import math
from hr.items import HrItem

class TencentSpider(scrapy.Spider):
    name = "tencent"
    allowed_domains = ["tencent.com"]
    start_urls = (
        'https://careers.tencent.com/tencentcareer/api/post/Query?pageIndex=1&pageSize=10',
    )

    def parse(self, response):
        data_lists = json.loads(response.text)
        data_list = data_lists['Data']['Posts']
        for data in data_list:
            item = HrItem()
            item['RecruitPostName1'] = data['RecruitPostName']  # 与items.py中定义的字段不一致 会报错
            item['CountryName'] = data['CountryName']
            item['PostURL'] = data['PostURL']
            item['LastUpdateTime'] = data['LastUpdateTime']
            yield item  # 数据传给piplines# 获取总页数
        pageNum=math.ceil(data_lists['Data']['Count']/10)
        # 设置第二页页码
        pageIndex = 2
        while pageIndex<=pageNum:
            next_url = "https://careers.tencent.com/tencentcareer/api/post/Query?pageIndex={}&pageSize=10".format(pageIndex)
            yield scrapy.Request(
                next_url,
                callback=self.parse,
                meta={"item":item}  # meta用法 在不同的解析函数中传递数据
            )
            pageIndex += 1

    def parse2(self, response):
        item = response.meta["item"]

 pipelines.py中处理数据

# -*- coding: utf-8 -*-

# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: http://doc.scrapy.org/en/latest/topics/item-pipeline.html
from pymongo import MongoClient
from hr.items import HrItem

client = MongoClient()
collection = client["hr"]["tencent"]

class HrPipeline(object):
    def process_item(self, item, spider):
        if isinstance(item, HrItem):  # 判断item是否属于Hritem
            print(item)
            collection.insert(dict(item))  # 导入到mongoDb前要先转化成字典

        return item

 scrapy配置信息settings.py

# -*- coding: utf-8 -*-

# Scrapy settings for yangguang project
#
# For simplicity, this file contains only settings considered important or
# commonly used. You can find more settings consulting the documentation:
#
#     https://docs.scrapy.org/en/latest/topics/settings.html
#     https://docs.scrapy.org/en/latest/topics/downloader-middleware.html
#     https://docs.scrapy.org/en/latest/topics/spider-middleware.html

BOT_NAME = 'yangguang'  # 项目名

SPIDER_MODULES = ['yangguang.spiders']  # 爬虫所在的位置
NEWSPIDER_MODULE = 'yangguang.spiders'  # 新建爬虫所在位置



# Crawl responsibly by identifying yourself (and your website) on the user-agent
USER_AGENT = 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.80 Safari/537.36'

# Obey robots.txt rules
ROBOTSTXT_OBEY = True  # True遵守robots协议 False不遵守协议

LOG_LEVEL = "WARNING"  # LOG日志等级


FEED_EXPORT_ENCODING = 'UTF-8'

# Configure maximum concurrent requests performed by Scrapy (default: 16)
#CONCURRENT_REQUESTS = 32  # 并发 同时最大数目为32

# Configure a delay for requests for the same website (default: 0)
# See https://docs.scrapy.org/en/latest/topics/settings.html#download-delay
# See also autothrottle settings and docs
#DOWNLOAD_DELAY = 3  # 下载延迟 每次下载前睡3秒 让爬虫更慢性
# The download delay setting will honor only one of:
#CONCURRENT_REQUESTS_PER_DOMAIN = 16  # 每个域名的最大并发请求数
#CONCURRENT_REQUESTS_PER_IP = 16  # 没个IP的最大并发请求数

# Disable cookies (enabled by default)
#COOKIES_ENABLED = False  # 是否开启COOKIE 默认是开启的

# Disable Telnet Console (enabled by default)
#TELNETCONSOLE_ENABLED = False  # 是否配置插件 默认是开启的

# Override the default request headers:  # 默认请求头
#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://docs.scrapy.org/en/latest/topics/spider-middleware.html
#SPIDER_MIDDLEWARES = {  # 爬虫中间件
#    'yangguang.middlewares.YangguangSpiderMiddleware': 543,
#}

# Enable or disable downloader middlewares
# See https://docs.scrapy.org/en/latest/topics/downloader-middleware.html
#DOWNLOADER_MIDDLEWARES = {  # 下载中间件
#    'yangguang.middlewares.YangguangDownloaderMiddleware': 543,
#}

# Enable or disable extensions
# See https://docs.scrapy.org/en/latest/topics/extensions.html
#EXTENSIONS = {  # 插件
#    'scrapy.extensions.telnet.TelnetConsole': None,
#}

# Configure item pipelines
# See https://docs.scrapy.org/en/latest/topics/item-pipeline.html
ITEM_PIPELINES = {  # pipelines 位置和权重
   'yangguang.pipelines.YangguangPipeline': 300,
}

# Enable and configure the AutoThrottle extension (disabled by default)  # AutoThrottle自动限速
# See https://docs.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)  # 缓存
# See https://docs.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'

 

posted on 2019-11-02 19:03  BZ易风  阅读(541)  评论(0编辑  收藏  举报