Shulou(Shulou.com)06/02 Report--

How to use Python to simulate login to Taobao, in view of this problem, this article introduces the corresponding analysis and solution in detail, hoping to help more partners who want to solve this problem to find a more simple and easy way.

Python simulated login to Taobao, I know, must have attracted you, let's have a look!

There are a lot of simulated login to Taobao on the Internet, but basically we use scrapy, pyppeteer, selenium and other libraries to simulate login, but so far we have not talked about these libraries, only about the requests library, so let's use the requests library to simulate login to Taobao today!

Before we talk about simulated login to Taobao, let's review the process of using requests library to simulate login to Douban and Sina Weibo: this kind of simulated login is relatively simple, and you only need to upload the user name and password to pass verification when you request to log in, that is to say, one step at a time!

And Taobao login is more complex, why is it complicated? Because Taobao login involves many parameters and requests more than once! Let's first talk about the Taobao login process, first understand the principle of the process, and then knock on the code, so that everyone can easily understand!

First, Taobao login process

In order to make it easy for everyone to understand, a non-standard Taobao login request sequence diagram is drawn.

Taobao ua parameters: ua (User-Agent) name user agent, Taobao ua parameters add browser, ip, computer, time and other information, and then encrypted generation, used in many places, not just login!

The above figure is a more detailed flow chart. From the code level, the simulated login to Taobao is divided into the following four steps:

After entering the user name, the browser will initiate a post request to Taobao (taobao.com) to determine whether slider verification occurs!

After the user enters the password, the browser issues another post request to taobao.com to verify that the username and password is correct, and if correct, a token is returned.

The browser takes token to Alibaba (alibaba.com) to exchange St codes!

After the browser obtains the St code, it takes the St code to obtain the cookies, and logs in successfully.

Here may be students will ask questions: why Taobao (taobao.com) passed the verification, but also take the token to Alibaba (alibaba.com) to exchange St codes? Let's talk about this later!

Second, the implementation of simulated login

Above we only talked about the general login process, here will first explain the operation of each step in detail, and then post the implementation code!

1. Determine whether a CAPTCHA is needed

At present, when we log on to Taobao, there is no slider CAPTCHA in most cases, and many attempts to log in and exit only once in the middle, so what on earth controls whether the slider CAPTCHA is needed?

As you can see from the image above, when the user name is entered, the browser will initiate a post request to verify whether a slider verification code is required. If true is returned, the slider verification code will appear! Otherwise, if it doesn't appear, it usually won't appear!

In the figure, we can see that two parameters are uploaded in this post request: username and ua!

As mentioned earlier, ua is a multi-information encryption parameter such as browser, ip, device information, etc., so guess whether Taobao's CAPTCHA appears not only from the account point of view, but also from the ip, device and other angles!

For example: a device may have logged in to a large number of accounts, then Taobao can get the device number from the ua parameter, and then restrict the device!

Once we know the process and request links and parameters, we can request them in code!

two。 Verify username and password

Here is step 5 in the sequence diagram above: request login. Here, more than 30 parameters, such as user name, ua parameter, encryption password, and so on, will be post to taobao.com for verification.

Let's implement it in code, don't be scared by so many parameters, they are all copied from the browser!

Look at the result of the request!

You can see that there is a token behind the link to apply for St code. What is the specific token for? we will analyze it later!

3. Apply for St code

Above we have applied for the token of taobao.com, and this step is to exchange token for St code.

Many people here may wonder: why does it take so much trouble to log in on Taobao? Can't you log in directly from taobao.com? Why verify the user name and password in taobao first, and then go to alibaba.com to get the St code to log in?

The framework of any company is the result of slow evolution, and I guess the initial Taobao login must not be so complicated. However, with the gradual growth of Alibaba, many business lines are divided, but these business lines are related to each other. For example, after users log in to their Taobao account, Tmall no longer needs to log in (note that the top-level domain names of Taobao and Tmall are different, so they cannot share cookis). In order to achieve this function, single sign-on appears.

Single sign-on (Single Sign On), referred to as SSO for short, is one of the most popular solutions for enterprise business integration. SSO is defined as that in multiple application systems, users only need to log in once to access all the applications that trust each other. Baidu encyclopedia

Many large enterprises almost have done single sign-on, then Ali's single sign-on system must be done by the parent company Alibaba (alibaba.com), all subsidiaries to call the parent company interface!

Let's come back to analyze why Taobao login is so complicated. It is easy to understand: the user data is here on Taobao, so we need to verify the user name and password on Taobao (taobao.com) now. By generating a token, the browser takes token to apply for a single sign-on code (St code) with Alibaba (alibaba.com). If Alibaba receives the request to verify token, it will return the St code. So the reason for using token for st code is single sign-on!

After understanding the design principle, the code implementation is very clear!

4. Log in using the st code

After we have successfully obtained the st code, we can log in. This step is to obtain the login cookies through the st code.

At this point, we have simulated login to Taobao successfully!

5. Get the Taobao nickname

In fact, above we have logged on to Taobao successfully and returned to the link of the user's home page, in order to further verify the login success, we asked Taobao user's home page to extract the Taobao nickname by the way!

III. Summary of this Python study course

After the overall lecture, let's sum it up a little bit, mainly from two aspects: the code structure and the existing problems:

1. Code structure

To release a code structure diagram, so that everyone can understand intuitively

These are the four steps we mentioned earlier to simulate login to Taobao, but here we are implemented in code!

two。 There are problems

Before writing this tutorial, you should also learn about it online, and then use your browser and Charles to practice it step by step. The most important thing is that you need to understand the general process of logging in on Taobao, otherwise you will have no idea when you actually operate it. Let's talk about the problems encountered at present and the existing problems.

First of all, the first problem is Taobao slider unlock, there is no good way to crack requests, after the introduction of some crawler framework, we will crack it!

Many attempts (more than 50 times) to log in and exit without a slider CAPTCHA.

Some people use proxy ip on the Internet, but I am useless here, as long as you are not super frequent and crawl a large number of data, generally big companies are not likely to seal ip, because there is a wide range of injuries and users, maybe one letter is the whole community.

In the second step to verify the user name and password, upload nearly 30 parameters, if you copy the username, ua, encrypted password into the verification or not, you can try to change those 30 parameters to your browser!

There will be an occasional error in steps 3 and 4, just try again!

This is the answer to the question about how to use Python to simulate login to Taobao. I hope the above content can be of some help to you. If you still have a lot of doubts to be solved, you can follow the industry information channel to learn more about it.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.