我们先通过百度搜索智联招聘,进入智联招聘官网,一看,傻眼了,需要登录才能查看招聘信息

image

没办法,用账号登录进去,登录后的网页如下:

image

输入职位名称点击搜索,显示如下网页:

image

把这个URL:https://sou.zhaopin.com/?jl=765&kw=软件测试&kt=3   拷贝下来,退出登录,再在浏览器地址栏输入复制下来的URL

image

哈哈,居然不用登录,也可以显示搜索的职位信息。好了,到这一步,目的达成。

接下来,我们来分析下页面,打开浏览器的开发者工具,选择Network,查看XHR,重新刷新一次页面,可以看到有多个异步加载信息

image

查看每个请求的返回消息,我们可以找到其中有个请求已JSON方式返回了符合要求的总职位数以及职位链接等信息

点击Headers,查看这个请求的URL:

image

我们把Request URL复制到浏览器中打开,没错就是我们需要的信息:

image

分析这个URL:https://fe-api.zhaopin.com/c/i/sou?pageSize=60&cityId=765&workExperience=-1&education=-1&companyType=-1&employmentType=-1&jobWelfareTag=-1&kw=软件测试&kt=3

我们可以知道:

1、pageSize:每页开始的值,第一页是0,第二是60,第三页是120,以此类推

2、cityId:是城市编码,直接输入城市名,也是可以的,比如:深圳

3、kw:搜索时输入的关键词,也就是职位名称

其他的字段都可以不变。

分析完了之后,我们可以开始写代码了:

我们先定义一个日志模块,保存爬虫过程中的日志:
log.py

# !usr/bin/env python3
# -*- coding:utf-8 -*- 
import logging
import os
from logging.handlers import TimedRotatingFileHandler
'''
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'''
class Logger:
    def __init__(self, logger_name='easton'):
        self.logger = logging.getLogger(logger_name)
        logging.root.setLevel(logging.NOTSET)
        self.log_file_name = 'spider_zhilian.log'
        self.backup_count = 5
        # 日志输出级别
        self.console_output_level = 'WARNING'
        self.file_output_level = 'DEBUG'
        # 日志输出格式
        pattern='%(asctime)s - %(levelname)s - %(message)s'
        self.formatter = logging.Formatter(pattern)
        # 日志路径
        if not os.path.exists('log'):
            os.mkdir('log')
        self.log_path = os.path.join(os.getcwd(),'log')


    def get_logger(self):
        """在logger中添加日志句柄并返回,如果logger已有句柄,则直接返回"""
        if not self.logger.handlers:
            console_handler=logging.StreamHandler()
            console_handler.setFormatter(self.formatter)
            console_handler.setLevel(self.console_output_level)
            self.logger.addHandler(console_handler)

            # 每天重新创建一个日志文件,最多保留backup_count份
            file_handler = TimedRotatingFileHandler(filename=os.path.join(self.log_path, self.log_file_name),
                                                    when='D',
                                                    interval=1,
                                                    backupCount=self.backup_count,
                                                    delay=True,
                                                    encoding='utf-8'
                                                    )
            file_handler.setFormatter(self.formatter)
            file_handler.setLevel(self.file_output_level)
            self.logger.addHandler(file_handler)
        return self.logger
logger = Logger().get_logger()

用一个简单的方法来实现增量爬取,把爬取的URL以hashlib加密,加密后返回32个字符,为了节省内存,只取中间的16个字符,这样也可以保证每个不同的URL有不同的加密字符,把爬取的URL加密字符保存到集合中,在爬取完成后,序列化保存到本地磁盘,下次再次爬取时,反序列化保存的URL到内存,对于已经爬取的URL不再爬取,这样就实现了增量爬取。

URL加密:

def hash_url(url):
    '''
    对URL进行加密,取加密后中间16位
    :param url:已爬取的URLL
    :return:加密的URL
    '''
    m = hashlib.md5()
    m.update(url.encode('utf-8'))
    return m.hexdigest()[8:-8]

序列化:

def save_progress(data, path):
    '''
    序列化保存已爬取的URL文件
    :param data:要保存的数据
    :param path:文件路径
    :return:
    '''
    try:
        with open(path, 'wb+') as f:
            pickle.dump(data, f)
            logger.info('save url file success!')
    except Exception as e:
        logger.error('save url file failed:',e)

save_progress

反序列化:

def load_progress( path):
    '''
    反序列化加载已爬取的URL文件
    :param path:
    :return:
    '''
    logger.info("load url file of already spider:%s" % path)
    try:
        with open(path, 'rb') as f:
            tmp = pickle.load(f)
            return tmp
    except:
        logger.info("not found url file of already spider!")
    return set()

load_progress

获取符合要求的职位总页数:从JSON消息中获取numFound字段,这个是总条数,再除以60,向上取整,返回的就是总页数

def get_page_nums(cityname,jobname):
    '''
    获取符合要求的工作页数
    :param cityname: 城市名
    :param jobname: 工作名
    :return: 总数
    '''
    url = r'https://fe-api.zhaopin.com/c/i/sou?pageSize=60&cityId={}&workExperience=-1&education=-1' \
          r'&companyType=-1&employmentType=-1&jobWelfareTag=-1&kw={}&kt=3'.format(cityname,jobname)
    logger.info('start get job count...')
    try:
        rec = requests.get(url)
        if rec.status_code==200:
            j = json.loads(rec.text)
            count_nums = j.get('data')['numFound']
            logger.info('get job count nums sucess:%s'%count_nums)
            page_nums = math.ceil(count_nums/60)
            logger.info('page nums:%s' % page_nums)
            return page_nums
    except Exception as e:
        logger.error('get job count nums faild:%s',e)

get_page_nums

获取每页的职位连接:JSON消息中的positionURL就是职位链接,在这里我们顺便获取职位的创建时间,更新时间,截止时间以及职位福利,以字典返回

def get_urls(start,cityname,jobname):
    '''
    获取每页工作详情URL以及部分职位信息
    :param start: 开始的工作条数
    :param cityname: 城市名
    :param jobname: 工作名
    :return: 字典
    '''
    url = r'https://fe-api.zhaopin.com/c/i/sou?start={}&pageSize=60&cityId={}&workExperience=-1&education=-1' \
          r'&companyType=-1&employmentType=-1&jobWelfareTag=-1&kw={}&kt=3'.format(start,cityname,jobname)
    logger.info('spider start:%s',start)
    logger.info('get current page all job urls...')
    url_list=[]
    try:
        rec = requests.get(url)
        if rec.status_code == 200:
            j = json.loads(rec.text)
            results = j.get('data').get('results')
            for job in results:
                empltype = job.get('emplType')  # 职位类型,全职or校园
                if empltype=='全职':
                    url_dict = {}
                    url_dict['positionURL'] = job.get('positionURL') # 职位链接
                    url_dict['createDate'] = job.get('createDate') # 招聘信息创建时间
                    url_dict['updateDate'] = job.get('updateDate') # 招聘信息更新时间
                    url_dict['endDate'] = job.get('endDate') # 招聘信息截止时间
                    positionLabel = job.get('positionLabel')
                    if positionLabel:
                        jobLight = (re.search('"jobLight":\[(.*?|[\u4E00-\u9FA5]+)\]',job.get('positionLabel'))) # 职位亮点
                        url_dict['jobLight'] = jobLight.group(1) if jobLight else None
                    else:
                        url_dict['jobLight'] = None
                    url_list.append(url_dict)
        logger.info('get current page all job urls success:%s' % len(url_list))
        return url_list
    except Exception as e:
        logger.error('get current page all job urls faild:%s', e)
        return None

get_urls

在浏览器中输入一个职位链接,查看页面信息

image

在这里我们以lxml来解析页面,解析结果以字典保存到生成器中

def get_job_info(url_list,old_url):
    '''
    获取工作详情
    :param url_list: 列表
    :return: 字典
    '''
    if url_list:
        for job in url_list:
            url = job.get('positionURL')
            h_url = hash_url(url)
            if not h_url in old_url:
                logger.info('spider url:%s'%url)
                try:
                    response = requests.get(url)
                    if response.status_code == 200:
                        s = etree.HTML(response.text)
                        job_stat = s.xpath('//div[@class="main1 cl main1-stat"]')[0]
                        stat_li_first = job_stat.xpath('./div[@class="new-info"]/ul/li[1]')[0]
                        job_name = stat_li_first.xpath('./h1/text()')[0] # 工作名
                        salary = stat_li_first.xpath('./div/strong/text()')[0] # 月薪
                        stat_li_second = job_stat.xpath('./div[@class="new-info"]/ul/li[2]')[0]
                        company_url = stat_li_second.xpath('./div[1]/a/@href')[0] # 公司URL
                        company_name = stat_li_second.xpath('./div[1]/a/text()')[0] # 公司名称
                        city_name = stat_li_second.xpath('./div[2]/span[1]/a/text()')[0] # 城市名
                        workingExp = stat_li_second.xpath('./div[2]/span[2]/text()')[0] # 工作经验
                        eduLevel = stat_li_second.xpath('./div[2]/span[3]/text()')[0] # 学历
                        amount = stat_li_second.xpath('./div[2]/span[4]/text()')[0] # 招聘人数
                        job_text = s.xpath('//div[@class="pos-ul"]//text()') # 工作要求
                        job_desc = ''
                        for job_item in job_text:
                            job_desc = job_desc+job_item.replace('\xa0','').strip('\n')
                        job_address_path = s.xpath('//p[@class="add-txt"]/text()') # 上班地址
                        job_address = job_address_path[0] if job_address_path else None
                        company_text = s.xpath('//div[@class="intro-content"]//text()') # 公司信息
                        company_info=''
                        for item in company_text:
                            company_info = company_info+item.replace('\xa0','').strip('\n')
                        promulgator = s.xpath('//ul[@class="promulgator-ul cl"]/li')
                        compant_industry = promulgator[0].xpath('./strong//text()')[0] #公司所属行业
                        company_type = promulgator[1].xpath('./strong/text()')[0] #公司类型:民营,国企,上市
                        totall_num = promulgator[2].xpath('./strong/text()')[0] #公司总人数
                        company_addr = promulgator[4].xpath('./strong/text()')[0].strip() #公司地址
                        logger.info('get job info success!')
                        old_url.add(h_url)
                        yield {
                            'job_name':job_name, # 工作名称
                            'salary':salary, # 月薪
                            'company_name':company_name, # 公司名称
                            'eduLevel':eduLevel, # 学历
                            'workingExp':workingExp, # 工作经验
                            'amount':amount, # 招聘总人数
                            'jobLight':job.get('jobLight'), # 职位亮点
                            'city_name':city_name, # 城市
                            'job_address':job_address, # 上班地址
                            'createDate':job.get('createDate'), # 创建时间
                            'updateDate':job.get('updateDate'), # 更新时间
                            'endDate':job.get('endDate'), # 截止日期
                            'compant_industry':compant_industry, # 公司所属行业
                            'company_type':company_type, # 公司类型
                            'totall_num':totall_num, # 公司总人数
                            'company_addr':company_addr, # 公司地址
                            'job_desc':job_desc, # 岗位职责
                            'job_url':'url', # 职位链接
                            'company_info':company_info, # 公司信息
                            'company_url':company_url # 公司链接
                        }
                except Exception as e:
                    logger.error('get job info failed:',url,e)

get_job_info

输出到CSV

headers = ['职业名', '月薪', '公司名', '学历', '经验', '招聘人数', '公司亮点','城市', '上班地址',
               '创建时间', '更新时间', '截止时间', '行业', '公司类型', '公司总人数', '公司地址',
               '岗位描述', '职位链接', '信息', '公司网址']
def write_csv_headers(csv_filename):
    with open(csv_filename,'a',newline='',encoding='utf-8-sig') as f:
        f_csv = csv.DictWriter(f,headers)
        f_csv.writeheader()

def save_csv(csv_filename,data):
    with open(csv_filename,'a+',newline='',encoding='utf-8-sig') as f:
        f_csv = csv.DictWriter(f,data.keys())
        f_csv.writerow(data)

csv

最后就是主函数了:

def main():
    if not os.path.exists(output_path):
        os.mkdir(output_path)
    for jobname in job_names:
        for cityname in city_names:
            logger.info('*'*10+'start spider '+'jobname:'+jobname+'city:'+cityname+'*'*10)
            total_page = get_page_nums(cityname,jobname)
            old_url = load_progress('old_url.txt')
            csv_filename=output_path+'/{0}_{1}.csv'.format(jobname,cityname)
            if not os.path.exists(csv_filename):
                write_csv_headers(csv_filename)
            for i in range(int(total_page)):
                urls = get_urls(i*60, cityname, jobname)
                data = get_job_info(urls, old_url)
                for d in data:
                    save_csv(csv_filename,d)
            save_progress(old_url,'old_url.txt')
            logger.info('*'*10+'jobname:'+jobname+'city:'+cityname+' spider finished!'+'*'*10)

main

打印爬虫耗时总时间:

city_names = ['深圳','广州']
job_names = ['软件测试','数据分析']
output_path = 'output'
if __name__=='__main__':
    start_time = datetime.datetime.now()
    logger.info('*'*20+"start running spider!"+'*'*20)
    main()
    end_time = datetime.datetime.now()
    logger.info('*'*20+"spider finished!Running time:%s"%(start_time-end_time) + '*'*20)
    print("Running time:%s"%(start_time-end_time))

本文转载:CSDN博客