jwt token结构
"token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJVc2VySWQiOjIsImV4cCI6MTY0MjQxNjg0NSwiaWF0IjoxNjQxODEyMDQ1LCJpc3MiOiJ5YW5ncWlhby5vcmcvZ2luQmFzZSIsInN1YiI6InVzZXIgdG9rZW4ifQ.KfbhacQK2pys7cILljfKco34nDSffJJHHTbRzBUjRBw"
1-协议
echo eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9 |base64 -d
{"alg":"HS256","typ":"JWT"}
2-data
echo eyJVc2VySWQiOjIsImV4cCI6MTY0MjQxNjg0NSwiaWF0IjoxNjQxODEyMDQ1LCJpc3MiOiJ5YW5ncWlhby5vcmcvZ2luQmFzZSIsInN1YiI6InVzZXIgdG9rZW4ifQ |base64 -d
{"UserId":2,"exp":1642416845,"iat":1641812045,"iss":"sre/proBase","sub":"user token"}
3-hash(1,2,jwtkey)