python爬虫如何爬知乎的话题？

摘要：有什么不懂得麻烦去去转盘网找我，因为这个也是我开发的，上面会及时更新群号，这里不留号啥的，以免被系统给了。

因为要做观点，观点的屋子类似于知乎的话题，所以得想办法把他给爬下来，搞了半天最终还是妥妥的搞定了，代码是python写的，不懂得麻烦自学哈！懂得直接看代码，绝对可用

#coding:utf-8
"""
@author:haoning
@create time:2015.8.5
"""
from __future__ import division  # 精确除法
from Queue import Queue
from __builtin__ import False
import json
import os
import re
import platform
import uuid
import urllib
import urllib2
import sys
import time
import MySQLdb as mdb
from bs4 import BeautifulSoup

reload(sys)
sys.setdefaultencoding( "utf-8" )

headers = {
   "User-Agent" : "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:35.0) Gecko/20100101 Firefox/35.0",
   "Content-Type":"application/x-www-form-urlencoded; charset=UTF-8",
   "X-Requested-With":"XMLHttpRequest",
   "Referer":"https://www.zhihu.com/topics",
   "Cookie":"__utma=51854390.517069884.1416212035.1416212035.1416212035.1; q_c1=c02bf44d00d240798bfabcfc95baeb56|1455778173000|1416205243000; _za=b1c8ae35-f986-46a2-b24a-cb9359dc6b2a; aliyungf_tc=AQAAAJ1m71jL1woArKqF22VFnL/wRy6C; _xsrf=9d494558f9271340ab24598d85b2a3c8; cap_id="MDNiMjcwM2U0MTRhNDVmYjgxZWVhOWI0NTA2OGU5OTg=|1455864276|2a4ce8247ebd3c0df5393bb5661713ad9eec01dd"; n_c=1; _alicdn_sec=56c6ba4d556557d27a0f8c876f563d12a285f33a"
}

DB_HOST = "127.0.0.1"
DB_USER = "root"
DB_PASS = "root"

queue= Queue() #接收队列
nodeSet=set()
keywordSet=set()
stop=0
offset=-20
level=0
maxLevel=7
counter=0
base=""

conn = mdb.connect(DB_HOST, DB_USER, DB_PASS, "zhihu", charset="utf8")
conn.autocommit(False)
curr = conn.cursor()

def get_html(url):
    try:
        req = urllib2.Request(url)
        response = urllib2.urlopen(req,None,3) #在这里应该加入代理
        html = response.read()
        return html
    except:
        pass
    return None

def getTopics():
    url = "https://www.zhihu.com/topics"
    print url
    try:
        req = urllib2.Request(url)
        response = urllib2.urlopen(req) #鍦ㄨ繖閲屽簲璇ュ姞鍏ヤ唬鐞�
        html = response.read().decode("utf-8")
        print html
        soup = BeautifulSoup(html)
        lis = soup.find_all("li", {"class" : "zm-topic-cat-item"})
        
        for li in lis:
            data_id=li.get("data-id")
            name=li.text
            curr.execute("select id from classify_new where name=%s",(name))
            y= curr.fetchone()
            if not y:
                curr.execute("INSERT INTO classify_new(data_id,name)VALUES(%s,%s)",(data_id,name))
        conn.commit()
    except Exception as e:
        print "get topic error",e
        

def get_extension(name):  
    where=name.rfind(".")
    if where!=-1:
        return name[where:len(name)]
    return None


def which_platform():
    sys_str = platform.system()
    return sys_str

def GetDateString():
    when=time.strftime("%Y-%m-%d",time.localtime(time.time()))
    foldername = str(when)
    return foldername 

def makeDateFolder(par,classify):
    try:
        if os.path.isdir(par):
            newFolderName=par + "//" + GetDateString() + "//"  +str(classify)
            if which_platform()=="Linux":
                newFolderName=par + "/" + GetDateString() + "/" +str(classify)
            if not os.path.isdir( newFolderName ):
                os.makedirs( newFolderName )
            return newFolderName
        else:
            return None 
    except Exception,e:
        print "kk",e
    return None 

def download_img(url,classify):
    try:
        extention=get_extension(url)
        if(extention is None):
            return None
        req = urllib2.Request(url)
        resp = urllib2.urlopen(req,None,3)
        dataimg=resp.read()
        name=str(uuid.uuid1()).replace("-","")+"_www.guandn.com"+extention
        top="E://topic_pic"
        folder=makeDateFolder(top, classify)
        filename=None
        if folder is not None:
            filename  =folder+"//"+name
        try:
            if "e82bab09c_m" in str(url):
                return True
            if not os.path.exists(filename):
                file_object = open(filename,"w+b")
                file_object.write(dataimg)
                file_object.close()
                return "/room/default/"+GetDateString()+"/"+str(classify)+"/"+name
            else:
                print "file exist"
                return None
        except IOError,e1:
            print "e1=",e1
            pass
    except Exception as e:
        print "eee",e
        pass
    return None #如果没有下载下来就利用原来网站的链接

def getChildren(node,name):
    global queue,nodeSet
    try:
        url="https://www.zhihu.com/topic/"+str(node)+"/hot"
        html=get_html(url)
        if html is None:
            return
        soup = BeautifulSoup(html)
        p_ch="父话题"
        node_name=soup.find("div", {"id" : "zh-topic-title"}).find("h1").text
        topic_cla=soup.find("div", {"class" : "child-topic"})
        if topic_cla is not None:
            try:
                p_ch=str(topic_cla.text)
                aList = soup.find_all("a", {"class" : "zm-item-tag"}) #获取所有子节点
                if u"子话题" in p_ch:
                    for a in aList:
                        token=a.get("data-token")
                        a=str(a).replace("
","").replace("	","").replace("
","")
                        start=str(a).find(">")
                        end=str(a).rfind("")
                        new_node=str(str(a)[start+1:end])
                        curr.execute("select id from rooms where name=%s",(new_node)) #先保证名字绝不相同
                        y= curr.fetchone()
                        if not y:
                            print "y=",y,"new_node=",new_node,"token=",token
                            queue.put((token,new_node,node_name))
            except Exception as e:
                print "add queue error",e
    except Exception as e:
        print "get html error",e
        
    

def getContent(n,name,p,top_id):
    try:
        global counter
        curr.execute("select id from rooms where name=%s",(name)) #先保证名字绝不相同
        y= curr.fetchone()
        print "exist?? ",y,"n=",n
        if not y:
            url="https://www.zhihu.com/topic/"+str(n)+"/hot"
            html=get_html(url)
            if html is None:
                return
            soup = BeautifulSoup(html)
            title=soup.find("div", {"id" : "zh-topic-title"}).find("h1").text
            pic_path=soup.find("a",{"id":"zh-avartar-edit-form"}).find("img").get("src")
            description=soup.find("div",{"class":"zm-editable-content"})
            if description is not None:
                description=description.text
                
            if (u"未归类" in title or u"根话题" in title): #允许入库，避免死循环
                description=None
                
            tag_path=download_img(pic_path,top_id)
            print "tag_path=",tag_path
            if (tag_path is not None) or tag_path==True:
                if tag_path==True:
                    tag_path=None
                father_id=2 #默认为杂谈
                curr.execute("select id from rooms where name=%s",(p))
                results = curr.fetchall()
                for r in results:
                    father_id=r[0]
                name=title
                curr.execute("select id from rooms where name=%s",(name)) #先保证名字绝不相同
                y= curr.fetchone()
                print "store see..",y
                if not y:
                    friends_num=0
                    temp = time.time()
                    x = time.localtime(float(temp))
                    create_time = time.strftime("%Y-%m-%d %H:%M:%S",x) # get time now
                    create_time
                    creater_id=None
                    room_avatar=tag_path
                    is_pass=1
                    has_index=0
                    reason_id=None  
                    #print father_id,name,friends_num,create_time,creater_id,room_avatar,is_pass,has_index,reason_id
                    ######################有资格入库的内容
                    counter=counter+1
                    curr.execute("INSERT INTO rooms(father_id,name,friends_num,description,create_time,creater_id,room_avatar,is_pass,has_index,reason_id)VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)",(father_id,name,friends_num,description,create_time,creater_id,room_avatar,is_pass,has_index,reason_id))
                    conn.commit() #必须时时进入数据库，不然找不到父节点
                    if counter % 200==0:
                        print "current node",name,"num",counter
    except Exception as e:
        print "get content error",e       

def work():
    global queue
    curr.execute("select id,node,parent,name from classify where status=1")
    results = curr.fetchall()
    for r in results:
        top_id=r[0]
        node=r[1]
        parent=r[2]
        name=r[3]
        try:
            queue.put((node,name,parent)) #首先放入队列
            while queue.qsize() >0:
                n,p=queue.get() #顶节点出队
                getContent(n,p,top_id)
                getChildren(n,name) #出队内容的子节点
            conn.commit()
        except Exception as e:
            print "what"s wrong",e  
            
def new_work():
    global queue
    curr.execute("select id,data_id,name from classify_new_copy where status=1")
    results = curr.fetchall()
    for r in results:
        top_id=r[0]
        data_id=r[1]
        name=r[2]
        try:
            get_topis(data_id,name,top_id)
        except:
            pass


def get_topis(data_id,name,top_id):
    global queue
    url = "https://www.zhihu.com/node/TopicsPlazzaListV2"
    isGet = True;
    offset = -20;
    data_id=str(data_id)
    while isGet:
        offset = offset + 20
        values = {"method": "next", "params": "{"topic_id":"+data_id+","offset":"+str(offset)+","hash_id":""}"}
        try:
            msg=None
            try:
                data = urllib.urlencode(values)
                request = urllib2.Request(url,data,headers)
                response = urllib2.urlopen(request,None,5)
                html=response.read().decode("utf-8")
                json_str = json.loads(html)
                ms=json_str["msg"]
                if len(ms) <5:
                    break
                msg=ms[0]
            except Exception as e:
                print "eeeee",e
            #print msg
            if msg is not None:
                soup = BeautifulSoup(str(msg))
                blks = soup.find_all("div", {"class" : "blk"})
                for blk in blks:
                    page=blk.find("a").get("href")
                    if page is not None:
                        node=page.replace("/topic/","") #将更多的种子入库
                        parent=name
                        ne=blk.find("strong").text
                        try:
                            queue.put((node,ne,parent)) #首先放入队列
                            while queue.qsize() >0:
                                n,name,p=queue.get() #顶节点出队
                                size=queue.qsize()
                                if size > 0:
                                    print size
                                getContent(n,name,p,top_id)
                                getChildren(n,name) #出队内容的子节点
                            conn.commit()
                        except Exception as e:
                            print "what"s wrong",e  
        except urllib2.URLError, e:
            print "error is",e
            pass 
            
        
if __name__ == "__main__":
    i=0
    while i<400:
        new_work()
        i=i+1

说下数据库的问题，我这里就不传附件了，看字段自己建立，因为这确实太简单了，我是用的mysql，你看自己的需求自己建。

有什么不懂得麻烦去去转盘网找我，因为这个也是我开发的，上面会及时更新qq群号，这里不留qq号啥的，以免被系统给K了。