Python爬虫实践：优志愿 院校列表

https://www.youzy.cn/tzy/search/colleges/collegeList

获取目标网址等信息

打开开发人员工具（F12），拿到调用接口的地址，以及接口请求参数等信息，如下

curl 'https://uwf7de983aad7a717eb.youzy.cn/youzy.dms.basiclib.api.college.query' \-H 'Accept: */*' \-H 'Accept-Language: zh-CN,zh;q=0.9' \-H 'Connection: keep-alive' \-H 'Content-Type: application/json' \-H 'Origin: https://pv4y-pc.youzy.cn' \-H 'Referer: https://pv4y-pc.youzy.cn/' \-H 'Sec-Fetch-Dest: empty' \-H 'Sec-Fetch-Mode: cors' \-H 'Sec-Fetch-Site: same-site' \-H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36 Edg/110.0.1587.63' \-H 'sec-ch-ua: "Chromium";v="110", "Not A(Brand";v="24", "Microsoft Edge";v="110"' \-H 'sec-ch-ua-mobile: ?0' \-H 'sec-ch-ua-platform: "macOS"' \-H 'u-sign: e79c2c67e9060725be683594244ec10f' \-H 'u-token;' \--data-raw '{"keyword":"","provinceNames":[],"natureTypes":[],"eduLevel":"","categories":[],"features":[],"pageIndex":4,"pageSize":20,"sort":11}' \--compressed

接口调用

第一次调用，按最简单的方案来进行：直接使用curl中的请求头以及参数，不做任何改动

该方法的好处是先将接口调通，不掺和其他外部因素

来，直接上代码

import requestsurl = 'https://uwf7de983aad7a717eb.youzy.cn/youzy.dms.basiclib.api.college.query'data = '{"keyword":"","provinceNames":[],"natureTypes":[],"eduLevel":"","categories":[],"features":[],"pageIndex":4,"pageSize":20,"sort":11}'headers = {'Accept': '*/*','Accept-Language': 'zh-CN,zh;q=0.9','Connection': 'keep-alive','Content-Type': 'application/json','Origin': 'https://pv4y-pc.youzy.cn','Referer': 'https://pv4y-pc.youzy.cn/','Sec-Fetch-Dest': 'empty','Sec-Fetch-Mode': 'cors','Sec-Fetch-Site': 'same-site','User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36 Edg/110.0.1587.63','sec-ch-ua': '"Chromium";v="110", "Not A(Brand";v="24", "Microsoft Edge";v="110"','sec-ch-ua-mobile': '?0','sec-ch-ua-platform': 'macOS','Accept-Encoding': 'gzip, deflate, br','Host': 'uwf7de983aad7a717eb.youzy.cn','u-sign': 'e79c2c67e9060725be683594244ec10f'
}response = requests.post(url, headers=headers, data=data)
print('response-->', response.text)

代码执行结果如下

进阶调用

通过从curl中获取相关参数，成功的进行了接口调用

此时，我们修改一下分页参数，来获取第2页的数据，提示身份鉴权失败

response--> {"code":"401","message":"身份授权失败","fullMessage":"","timestamp":"2023-03-06T16:10:56.1799746+08:00","isSuccess":false}

通过实验发现，修改任意参数，都会提示鉴权失败

所有证据都证明着这里有猫腻

观察请求体，参数都挺正常，除了u-sign

寻找u-sign

使用开发人员工具里的搜索功能，来看下u-sign是在哪里赋值

找到文件之后，继续在文件内搜索u-sign

可能会找到多个符合项，这时可以通过数据翻页debug的方式，来确定具体哪一项符合我们的预期

分析u-sign生成代码

return e.headers = {"Content-Type": "application/json","u-sign": o(e.url, e.data), // 生成u-sign"u-token": p.getOrLoadUToken()}

继续debug，找到方法o的代码

    "339a": function(e, t, r) {r("ac1f"),r("1276"),r("159b"),r("99af"),r("1e25"),r("b64b");var n = r("6821");e.exports = function(e, t) {var r, i = "9SASji5OWnG41iRKiSvTJHlXHmRySRp1", o = "", a = t || {}, s = (e = e || "").split("?");if (s.length > 0 && (r = s[1]),r) {var u = r.split("&"), c = "";u.forEach((function(e) {var t = e.split("=");c += "".concat(t[0], "=").concat(encodeURI(t[1]), "&")})),o = "".concat(_.trimEnd(c, "&"), "&").concat(i)} else// 走的这里！！o = Object.keys(a).length > 0 ? "".concat(JSON.stringify(a), "&").concat(i) : "&".concat(i);return o = o.toLowerCase(),n(o) // 做了一次加密操作}},

方法o中做了一个字符串拼接，并执行了方法n（加密操作），代码如下

            e.exports = function(e, r) {if (null == e)throw new Error("Illegal argument " + e);var n = t.wordsToBytes(a(e, r));return r && r.asBytes ? n : r && r.asString ? o.bytesToString(n) : t.bytesToHex(n)}

加密代码没有完全看明白
通过网上的案例+使用加密工具，强行试出来是加密方式是md5
在线加密工具：在线加密解密 - chahuo.com

最后附上完整代码

from hashlib import md5import requestsurl = 'https://uwf7de983aad7a717eb.youzy.cn/youzy.dms.basiclib.api.college.query'data = '{"keyword":"","provinceNames":[],"natureTypes":[],"eduLevel":"","categories":[],"features":[],"pageIndex":2,"pageSize":20,"sort":11}'def u(tt):en_key = '9SASji5OWnG41iRKiSvTJHlXHmRySRp1'result = tt.lower() + '&' + en_key.lower()print('result', result)return resultdef get_u_sign(data):sign_data = u(data)return md5(sign_data.encode()).hexdigest()headers = {'Accept': '*/*','Accept-Language': 'zh-CN,zh;q=0.9','Connection': 'keep-alive','Content-Type': 'application/json','Origin': 'https://pv4y-pc.youzy.cn','Referer': 'https://pv4y-pc.youzy.cn/','Sec-Fetch-Dest': 'empty','Sec-Fetch-Mode': 'cors','Sec-Fetch-Site': 'same-site','User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36 Edg/110.0.1587.63','sec-ch-ua': '"Chromium";v="110", "Not A(Brand";v="24", "Microsoft Edge";v="110"','sec-ch-ua-mobile': '?0','sec-ch-ua-platform': 'macOS','Accept-Encoding': 'gzip, deflate, br','Host': 'uwf7de983aad7a717eb.youzy.cn','u-sign': get_u_sign(data)
}response = requests.post(url, headers=headers, data=data)
print('response-->', response.text)