#1: What are session_key and openId? session_key
The official description is:
session_key is the key generated by the WeChat server for encrypting and signing user data
Use of session_key
(1) For wx.getUserInfo() The interface obtains the "ciphertext in user information" for decryption.
(2) "Process it slightly" and use it to maintain the login state of the applet.
"A little processing" is roughly as follows:
(1) Generate a random number (officially called it 3rd_session)
(2) Use this random number as the session key, session_key + openid as the value.
That is: session[3rd_session]=session_key+openid
openIdopenId: the user’s unique identification
That is: the unique identification of each WeChat user in your mini program.
#2: How to obtain session_key and openId. The official HTTP interface is provided:
https://api.weixin.qq. com/sns/jscode2session?appid=APPID&secret=SECRET&js_code=JSCODE&grant_type=authorization_code Obtaining steps:
(1) Obtain appid, secret, js_code
(2) Use appid, secret, js_code to replace the APPID and the above interface address respectively. SECRET, JSCODE, others remain unchanged, and assembled into a complete address.
For example:
![1H5346002-0](media/14842017330009/1H5346002-0.png)
WeChat applet obtains session_key and openId (encryption, decryption, signature series)
![1H5345348-1](media/14842017330009/1H5345348-1.png)
3: Open this in "Browser" Address" or "simulate the browser's GET to execute this address in the background" can return the following JSON data (including openid, sessionkey)
WeChat applet obtains session_key and openId (encryption, decryption, signature series)
Summary: From steps 1, 2, and 3, as long as you get the appid, secret, and js_code, you can get the session_key and openId
4: Obtaining appid and secret
appid is the mini program ID
secret is the mini program key (AppSecret)
How to obtain: mini program background login URL: https://mp.weixin.qq.com/
After opening the mini program backend URL, registering, and logging in, you can find your AppID and AppSecret as shown below.
The WeChat mini program obtains session_key and openId (encryption, decryption, signature series)
Note: Currently, individuals cannot register for the mini program, and the scope of open registration is: enterprises, governments, media, and other organizations;
Of course, individuals can also register using this method.
Portal: http://www.moquu.com/v/372.html
5: How to obtain js_code by calling the wx.login() interface to obtain the login credentials (js_code)
WeChat applet obtains session_key and openId (encryption, decryption, signature series)
![1H5344U3-3](media/14842017330009/1H5344U3-3.png)
#6: Summarize the entire session_key acquisition process (1) Register the WeChat applet, log in to the background and obtain the appId and secret (key) in the settings
(2) Call wx.login () interface to obtain login credentials js_code
(3) Call the wx.request() interface to send js_code to the server background
(4) In the server background, the appId, secret, js_code
are known and then call the following official The provided http interface can be returned to obtain openId and session_key
The official http interface address is:
https://api.weixin.qq.com/sns/jscode2session?appid=APPID&secret=SECRET&js_code =JSCODE&grant_type=authorization_code
For more articles related to the WeChat applet login process, please pay attention to the PHP Chinese website!