1、安装拓展包

$ go get -u github.com/dgrijalva/jwt-go

2、发放token

func ReleaseToken(user *model.User) (tokenString string,err error) {
  expire := time.Now().Add(7 * 24 * time.Hour)
  claims := &Claims{
    UserId: user.ID,
    StandardClaims: jwt.StandardClaims{
      ExpiresAt: expire.Unix(),
      IssuedAt: time.Now().Unix(),
      Issuer: "oceanlearn.tech",
      Subject: "user token",
    },
  }
  token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
  tokenString, err = token.SignedString(jwtKey)
  if err != nil {
    return "", err
  }
  return

}

3、解析token

func ParseToken(tokenString string) (*jwt.Token, *Claims, error) {
  claims := &Claims{}
  token,err := jwt.ParseWithClaims(tokenString, claims, func(token *jwt.Token) (interface{}, error) {
    return jwtKey, nil
  })
  return token, claims, err
}

附：

var jwtKey = []byte("apple")

type Claims struct {
  UserId int
  jwt.StandardClaims
}

==============================手动分隔线====================

整个流程

1、用户输入账号密码发送到登录接口，若账号密码正确，则发放token，将此token返回给用户

2、用户后续每次请求，如访问个人信息接口，需要在请求头部加上此token

3、接口收到请求后，会判断token是否有效，若有效则解析token，找到用户id，从而获取用户信息

1、用户登录成功，发放token

token, err := common.ReleaseToken(user)
response.LoginSuccessfully(c, gin.H{"token":token})

2、用户请求头携带token

Authorization Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJVc2VySWQiOjE2LCJleHAiOjE2MTEwNDEwNDIsImlhdCI6MTYxMDQzNjI0MiwiaXNzIjoib2NlYW5sZWFybi50ZWNoIiwic3ViIjoidXNlciB0b2tlbiJ9.DRdyspxB7iSUxrawN6QpMR_-SeW7U_FV4E0fMf7BjQI

3、中间件判断token是否有效，获取信息，将用户信息注入到 gin.Context 中

func CheckJWTLogin() gin.HandlerFunc  {
  return func(c *gin.Context) {
    tokenString := c.GetHeader("Authorization")
    if tokenString == "" || !strings.HasPrefix(tokenString, "Bearer "){
      c.JSON(419, gin.H{"code":419, "msg":"unauthorized"})
      c.Abort()
      return
    }

    tokenString = tokenString[7:]
    _, claims, err := common.ParseToken(tokenString)
    if err != nil {
      c.JSON(419, gin.H{"code":419, "msg": err.Error()})
      c.Abort()
      return
    }

    userId := claims.UserId
    var user model.User
    dao.DB.First(&user, userId)
    c.Set("user", user)
    c.Next()
  }
}