为了能够将爬取到的数据存入本地数据库,现在本地创建一个mysql数据库example,然后
在数据库中建立一张表格douban_db,示例如下:
CREATE TABLE `douban_db` ( `url` varchar(20) NOT NULL, `direct` varchar(30), `performer` varchar(255), `type` varchar(30), `district` varchar(20) NOT NULL, `language` varchar(30), `date` varchar(30), `time` varchar(30), `alias` varchar(20) NOT NULL, `score` varchar(30), `comments` varchar(300), `scenario` varchar(300), `IMDb` varchar(30), PRIMARY KEY (`url`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8;
2.如果使用开源框架pyspider来进行爬虫的话,默认情况下,会把爬取到的结果存放到result.db这个sqilite数据库中,但是为了方便操作,我们将结果存放到mysql中。接下
来要做的一个操作就是重写on_result方法,实例化调用我们自己实现的SQL方法,具体
实例如下:
#!/usr/bin/env python # -*- encoding: utf-8 -*- # Created on 2015-03-20 09:46:20 # Project: douban_movie import re from pyspider.database.mysql.mysqldb import SQL from pyspider.libs.base_handler import * class Handler(BaseHandler): headers= { 'Accept':'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'Accept-Encoding':'gzip, deflate, sdch', 'Accept-Language':'zh-CN,zh;q=0.8', 'Cache-Control':'max-age=0', 'Connection':'keep-alive', 'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.101 Safari/537.36' } crawl_config = { 'headers' : headers, 'timeout' : 100 } @every(minutes=24 * 60) def on_start(self): self.crawl('http://movie.douban.com/tag/', callback=self.index_page) @config(age=10 * 24 * 60 * 60) def index_page(self, response): for each in response.doc("a[href^='http://www.douban.com/tag/']").items(): self.crawl(each.attr.href, callback=self.list_page) @config(age=10*24*60*60, priority=2) def list_page(self, response): for each in response.doc('.movie-list a').items(): self.crawl(each.attr.href, priority=9, callback=self.detail_page) @config(priority=3) def detail_page(self, response): return { 'url': response.url, 'title': response.doc('h1').text(), 'direct': ','.join(x.text() for x in response.doc("a[rel='v:directedBy']").items()), 'performer': ','.join(x.text() for x in response.doc("a[rel='v:starring']").items()), 'type': ','.join(x.text() for x in response.doc("span[property='v:genre']").items()), 'district': ''.join(x.text() for x in response.doc("a[rel='v:starring']").items()), 'language': ''.join(x.text() for x in response.doc("a[rel='v:starring']").items()), 'date': ','.join(x.text() for x in response.doc("span[property='v:initialReleaseDate']").items()), 'time': ','.join(x.text() for x in response.doc("span[property='v:runtime']").items()), 'alias': ''.join(x.text() for x in response.doc("a[rel='v:starring']").items()), 'score': response.doc('.rating_num').text(), 'comments': response.doc('html > body > div#wrapper > div#content > div.grid-16-8.clearfix > div.article > div#comments-section > div.mod-hd > h4 > i').text(), 'scenario': response.doc('html > body > div#wrapper > div#content > div.grid-16-8.clearfix > div.article > div.related-info > div#link-report.indent').text(), 'IMDb': response.doc('a[href^="http://www.imdb.com/title/"]').text(), } def on_result(self, result): if not result or not result['title']: return sql = SQL() sql.replace('douban_db',**result)
关于上面这段代码,有下面几点需要说明的:
a. 为了避免服务器判断出客户端在进行爬虫操作,从而禁止ip访问(具体表现为出现403禁止访问),我们需要在发出请求的时候加上一个http头,伪装成使用浏览器访问,具体用法如下:
headers= { 'Accept':'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'Accept-Encoding':'gzip, deflate, sdch', 'Accept-Language':'zh-CN,zh;q=0.8', 'Cache-Control':'max-age=0', 'Connection':'keep-alive', 'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.101 Safari/537.36' } crawl_config = { 'headers' : headers, 'timeout' : 100 }
b. @every(minutes=24 * 60)表示每天执行一次
@config(age=10 * 24 * 60 * 60)表示数据10天后就过期了
c. 接下来是一个比较重要的地方,重写on_result方法,相当于实现了一个多态,程序在最后返回时,会执行on_result方法,默认的情况下,on_result是将数据刷入sqlite中,但是如果我们需要将数据插入mysql中,就需要重写on_result方法,具体使用如下:
def on_result(self, result): if not result or not result['title']: return sql = SQL() sql.replace('example',**result)
注意这里的if not result or not result[‘title’]:这句判断很重要,不然的会会报错,提示result是未定义类型的。
3.在上面的额代码中,提到了实例化调用我们自己实现的SQL方法,并且引用了from pyspider.database.mysql.mysqldb import SQL这个库文件,那么就必须在这个目录下实现这个库,具体如下:
把下面内容文文放到pyspider/pyspider/database/mysql/目录下命名为mysqldb.py
# -*- encoding: utf-8 -*- from six import itervalues import mysql.connector from datetime import date, datetime, timedelta class SQL: username = 'root' # 数据库用户名 password = 'root' # 数据库密码 database = 'test' # 数据库 host = '127.0.0.1' # 数据库主机地址 connection = '' connect = True placeholder = '%s' def __init__(self): if self.connect: SQL.connect(self) def escape(self, string): return '`%s`' % string def connect(self): config = { 'user': SQL.username, 'password': SQL.password, 'host': SQL.host } if SQL.database != None: config['database'] = SQL.database try: cnx = mysql.connector.connect(**config) SQL.connection = cnx return True except mysql.connector.Error as err: if (err.errno == errorcode.ER_ACCESS_DENIED_ERROR): print 'The credentials you provided are not correct.' elif (err.errno == errorcode.ER_BAD_DB_ERROR): print 'The database you provided does not exist.' else: print 'Something went wrong: ', err return False def replace(self, tablename=None, **values): if SQL.connection == '': print 'Please connect first' return False tablename = self.escape(tablename) if values: _keys = ', '.join(self.escape(k) for k in values) _values = ', '.join([self.placeholder, ] * len(values)) sql_query = 'REPLACE INTO %s (%s) VALUES (%s)' % (tablename, _keys, _values) else: sql_query = 'REPLACE INTO %s DEFAULT VALUES' % tablename cur = SQL.connection.cursor() try: if values: cur.execute(sql_query, list(itervalues(values))) else: cur.execute(sql_query) SQL.connection.commit() return True except mysql.connector.Error as err: print ('An error occured: {}'.format(err)) return False
学习文档:http://blog.binux.me/2015/01/pyspider-tutorial-level-1-html-and-css-selector/
测试环境:http://demo.pyspider.org/
转载请注明:拈花古佛 » Pyspider把抓取的结果存入mysql数据库