Python爬虫实战第二例【二】

零.前言：

本文章借鉴：Python爬虫实战（五）：根据关键字爬取某度图片批量下载到本地（附上完整源码）_python爬虫下载图片-CSDN博客

大佬的文章里面有API的获取，在这里我就不赘述了。

一.实战目标：

对百度的图片进行爬取，利用代理IP实现批量下载。

二.实现效果：

实现批量下载指定内容的图片，存放到指定文件夹中：

三.代码实现

3.1分析网页

右键网页，点击检查，进入我们的Google开发者工具。

筛选出我们需要的文件（通过查找载荷寻找）

接下来，只需要构建我们的载荷：

3.2获取图片的URL链接

def get_img_url(keyword):
    #接口连接
    url = "https://image.baidu.com/search/acjson"
    #请求头
    header = {
        "User-Agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36"
    }
    #params参数
    params = {
        "tn": "resultjson_com",
        "logid": "7831763171415538646",
        "ipn": "rj",
        "ct": "201326592",
        "is":"",
        "fp":"result",
        "fr":"",
        "word":f"{keyword}",
        "queryWord":f"{keyword}",
        "cl":"2",
        "lm":"-1",
        "ie":"utf - 8",
        "oe":"utf - 8",
        "adpicid":"",
        "st":"",
        "z":"",
        "ic":"",
        "hd":"",
        "latest":"",
        "copyright":"",
        "s":"",
        "se":"",
        "tab":"",
        "width":"",
        "height":"",
        "face":"",
        "istype":"",
        "qc":"",
        "nc":"1",
        "expermode":"",
        "nojc":"",
        "isAsync":"",
        "pn":"1",
        "rn":"100",
        "gsm":"78",
        "1709030173834":""
    }
    #创建get请求
    r = requests.get(url=url,params=params,headers=header)
    #切换编码格式
    r.encoding = "utf-8"
    json_dict = r.json()
    #定位数据
    data_list = json_dict["data"]
    #存储链接
    url_list = []
    #循环取链接
    for i in data_list:
        if i:
            u = i["thumbURL"]
            url_list.append(u)
    return url_list

结果：

3.3实现代理

def get_ip():
    #代理API
    url = "你的代理API"
    while 1:
        try:
            r = requests.get(url,timeout=10)
        except:
            continue
        ip = r.text.strip()
        if "请求过于频繁" in ip:
            print("IP请求频繁")
            time.sleep(1)
            continue
        break
    proxies = {
        "https": f"{ip}"
    }
    return proxies

效果：

3.4实现爬虫

def get_down_img(img_url_list):
    #创建文件夹
    if not os.path.isdir("鞠婧祎"):
        os.mkdir("鞠婧祎")
    #定义图片编号
    n = 0
    header = {
        "User-Agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36"
    }
    times = 0
    while times < len(img_url_list):
        #获取代理IP
        proxies = get_ip()
        try:
            img_data = requests.get(url=img_url_list[times],headers=header,proxies=proxies,timeout=2)
        except Exception as e:
            print(e)
            continue
        #拼接图片存放地址和名字
        img_path = "鞠婧祎/" + str(n) + ".jpg"
        #写入图片
        with open(img_path,"wb") as f:
            f.write(img_data.content)
        n = n + 1
        times += 1

四、优化

上面基本实现了批量爬取图片的目的，但是在实际使用中可能会因为代理IP的质量问题，网络问题，导致爬取效率低下，在这里作者给出几点优化的空间：

1.设置timeout超时时间（秒/S）

2.使用requests.sessions类，构建一个sessions对象，设置连接重试次数。

3.使用多线程，分批爬取

具体实现，可以等作者后面慢慢更新，挖个大坑，记得催更。。。

五、全部代码

import requests
import time
import  os

def get_img_url(keyword):
    #接口连接
    url = "https://image.baidu.com/search/acjson"
    #请求头
    header = {
        "User-Agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36"
    }
    #params参数
    params = {
        "tn": "resultjson_com",
        "logid": "7831763171415538646",
        "ipn": "rj",
        "ct": "201326592",
        "is":"",
        "fp":"result",
        "fr":"",
        "word":f"{keyword}",
        "queryWord":f"{keyword}",
        "cl":"2",
        "lm":"-1",
        "ie":"utf - 8",
        "oe":"utf - 8",
        "adpicid":"",
        "st":"",
        "z":"",
        "ic":"",
        "hd":"",
        "latest":"",
        "copyright":"",
        "s":"",
        "se":"",
        "tab":"",
        "width":"",
        "height":"",
        "face":"",
        "istype":"",
        "qc":"",
        "nc":"1",
        "expermode":"",
        "nojc":"",
        "isAsync":"",
        "pn":"1",
        "rn":"100",
        "gsm":"78",
        "1709030173834":""
    }
    #创建get请求
    r = requests.get(url=url,params=params,headers=header)
    #切换编码格式
    r.encoding = "utf-8"
    json_dict = r.json()
    #定位数据
    data_list = json_dict["data"]
    #存储链接
    url_list = []
    #循环取链接
    for i in data_list:
        if i:
            u = i["thumbURL"]
            url_list.append(u)
            print(u)
    return url_list

def get_ip():
    #代理API
    url = "你的API"
    while 1:
        try:
            r = requests.get(url,timeout=10)
        except:
            continue
        ip = r.text.strip()
        if "请求过于频繁" in ip:
            print("IP请求频繁")
            time.sleep(1)
            continue
        break
    proxies = {
        "https": f"{ip}"
    }
    return proxies

def get_down_img(img_url_list):
    #创建文件夹
    if not os.path.isdir("鞠婧祎"):
        os.mkdir("鞠婧祎")
    #定义图片编号
    n = 0
    header = {
        "User-Agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36"
    }
    times = 0
    while times < len(img_url_list):
        #获取代理IP
        proxies = get_ip()
        try:
            img_data = requests.get(url=img_url_list[times],headers=header,proxies=proxies,timeout=2)
        except Exception as e:
            print(e)
            continue
        #拼接图片存放地址和名字
        img_path = "鞠婧祎/" + str(n) + ".jpg"
        #写入图片
        with open(img_path,"wb") as f:
            f.write(img_data.content)
        n = n + 1
        times += 1

if __name__ == "__main__":
    url_list = get_img_url("鞠婧祎")
    get_down_img(url_list)