掘金 后端 ( ) • 2024-07-03 10:36

什么是JWT

JWT,全称 JSON Web Token,是一种开放标准(RFC 7519),用于安全地在双方之间传递信息。尤其适用于身份验证和授权场景。JWT 的设计允许信息在各方之间安全地、 compactly(紧凑地)传输,因为其自身包含了所有需要的认证信息,从而减少了需要查询数据库或会话存储的需求。

JWT主要由三部分组成,通过.连接:

  1. Header(头部):描述JWT的元数据,通常包括类型(通常是JWT)和使用的签名算法(如HS256RS256等)。
  2. Payload(载荷):包含声明(claims),即用户的相关信息。这些信息可以是公开的,也可以是私有的,但应避免放入敏感信息,因为该部分可以被解码查看。载荷中的声明可以验证,但不加密。
  3. Signature(签名):用于验证JWT的完整性和来源。它是通过将Header和Payload分别进行Base64编码后,再与一个秘钥(secret)一起通过指定的算法(如HMAC SHA256)计算得出的。

JWT的工作流程大致如下:

  • 认证阶段:用户向服务器提供凭证(如用户名和密码)。服务器验证凭证无误后,生成一个JWT,其中包含用户标识符和其他声明,并使用秘钥对其进行签名。
  • 使用阶段:客户端收到JWT后,可以在后续的每个请求中将其放在HTTP请求头中发送给服务器,以此证明自己的身份。
  • 验证阶段:服务器收到JWT后,会使用相同的秘钥验证JWT的签名,确保其未被篡改,并检查过期时间等其他声明,从而决定是否允许执行请求。

JWT的优势在于它的无状态性,服务器不需要存储会话信息,这减轻了服务器的压力,同时也方便了跨域认证。但需要注意的是,JWT的安全性依赖于秘钥的安全保管以及对JWT过期时间等的合理设置。

API设计

这里设计两个公共接口和一个受保护的接口。

API 描述 /api/login 公开接口。用于用户登录 /api/register 公开接口。用于用户注册 /api/admin/user 保护接口,需要验证JWT

开发准备

初始化项目目录并切换进入

mkdir gin-jwt
cd gin-jwt

使用go mod初始化工程

go mod init gin-jwt

安装依赖

go get -u github.com/gin-gonic/gin
go get -u gorm.io/gorm
go get -u gorm.io/driver/postgres
go get -u github.com/golang-jwt/jwt/v5
go get -u github.com/joho/godotenv
go get -u golang.org/x/crypto

创建第一个API

一开始我们可以在项目的根目录中创建文件main.go

touch main.go

添加以下内容

package main

import (
"net/http"

"github.com/gin-gonic/gin"
)

func main() {
r := gin.Default()
public := r.Group("/api")
{
public.POST("/register", func(c *gin.Context) {
c.JSON(http.StatusOK, gin.H{
"data": "test. register api",
})
})
}

r.Run("0.0.0.0:8000")
}

测试运行

go run main.go

客户端测试。正常的话会有以下输出

$ curl -X POST http://127.0.0.1:8000/api/register
{"data":"test. register api"}

完善register接口

现在register接口已经准备好了,但一般来说我们会把接口业务逻辑放在单独的文件中,而不是和接口定义写在一块。

创建一个控制器的包目录,并添加文件

mkdir controllers
touch controllers/auth.go

auth.go文件内容

package controllers

import (
"net/http"

"github.com/gin-gonic/gin"
)

func Register(c *gin.Context) {
c.JSON(http.StatusOK, gin.H{
"data": "hello, this is register endpoint",
})
}

更新main.go文件

package main

import (
"github.com/gin-gonic/gin"

"gin-jwt/controllers"
)

func main() {
r := gin.Default()
public := r.Group("/api")
{
public.POST("/register", controllers.Register)
}

r.Run("0.0.0.0:8000")
}

重新运行测试

go run main.go

客户端测试

$ curl -X POST http://127.0.0.1:8000/api/register
{"data":"hello, this is register endpoint"}

解析register的客户端请求

客户端请求register api需要携带用户名和密码的参数,服务端对此做解析。编辑文件controllers/auth.go

package controllers

import (
"net/http"

"github.com/gin-gonic/gin"
)

// /api/register的请求体
type ReqRegister struct {
Username string `json:"username" binding:"required"`
Password string `json:"password" binding:"required"`
}

func Register(c *gin.Context) {
var req ReqRegister

if err := c.ShouldBindBodyWithJSON(&req); err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"data": err.Error(),
})
return
}
c.JSON(http.StatusOK, gin.H{
"data": req,
})
}

客户端请求测试

$ curl -X POST http://127.0.0.1:8000/api/register -d '{"username": "zhangsan", "password": "123456"}' -H 'Content-Type=application/json'

{"data":{"username":"zhangsan","password":"123456"}}

连接关系型数据库

一般会将数据保存到专门的数据库中,这里用PostgreSQL来存储数据。Postgres使用docker来安装。安装完postgres后,创建用户和数据库:

create user ginjwt encrypted password 'ginjwt';
create database ginjwt owner = ginjwt;

创建目录models,这个目录将包含连接数据库和数据模型的代码。

mkdir models

编辑文件models/setup.go

package models

import (
"fmt"
"log"
"os"

"github.com/joho/godotenv"
"gorm.io/driver/postgres"
"gorm.io/gorm"
)

var DB *gorm.DB

func ConnectDatabase() {
err := godotenv.Load(".env")
if err != nil {
log.Fatalf("Error loading .env file. %v\n", err)
}

// DbDriver := os.Getenv("DB_DRIVER")
DbHost := os.Getenv("DB_HOST")
DbPort := os.Getenv("DB_PORT")
DbUser := os.Getenv("DB_USER")
DbPass := os.Getenv("DB_PASS")
DbName := os.Getenv("DB_NAME")

dsn := fmt.Sprintf("host=%s port=%s user=%s dbname=%s sslmode=disable TimeZone=Asia/Shanghai password=%s", DbHost, DbPort, DbUser, DbName, DbPass)

DB, err = gorm.Open(postgres.Open(dsn), &gorm.Config{})
if err != nil {
log.Fatalf("Connect to database failed, %v\n", err)
} else {
log.Printf("Connect to database success, host: %s, port: %s, user: %s, dbname: %s\n", DbHost, DbPort, DbUser, DbName)
}

// 迁移数据表
DB.AutoMigrate(&User{})
}

新建并编辑环境配置文件.env

DB_HOST=127.0.0.1
DB_PORT=5432
DB_USER=ginjwt
DB_PASS=ginjwt
DB_NAME=ginjwt

创建用户模型,编辑代码文件models/user.go

package models

import (
"html"
"strings"

"golang.org/x/crypto/bcrypt"
"gorm.io/gorm"
)

type User struct {
gorm.Model
Username string `gorm:"size:255;not null;unique" json:"username"`
Password string `gorm:"size:255;not null;" json:"password"`
}

func (u *User) SaveUser() (*User, error) {
err := DB.Create(&u).Error
if err != nil {
return &User{}, err
}
return u, nil
}

// 使用gorm的hook在保存密码前对密码进行hash
func (u *User) BeforeSave(tx *gorm.DB) error {
hashedPassword, err := bcrypt.GenerateFromPassword([]byte(u.Password), bcrypt.DefaultCost)
if err != nil {
return err
}
u.Password = string(hashedPassword)
u.Username = html.EscapeString(strings.TrimSpace(u.Username))
return nil
}

更新main.go

package main

import (
"github.com/gin-gonic/gin"

"gin-jwt/controllers"
"gin-jwt/models"
)

func init() {
models.ConnectDatabase()
}

func main() {
r := gin.Default()
public := r.Group("/api")
{
public.POST("/register", controllers.Register)
}

r.Run("0.0.0.0:8000")
}

更新controllers/auth.go

package controllers

import (
"net/http"

"gin-jwt/models"

"github.com/gin-gonic/gin"
)

// /api/register的请求体
type ReqRegister struct {
Username string `json:"username" binding:"required"`
Password string `json:"password" binding:"required"`
}

func Register(c *gin.Context) {
var req ReqRegister

if err := c.ShouldBindBodyWithJSON(&req); err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"data": err.Error(),
})
return
}

u := models.User{
Username: req.Username,
Password: req.Password,
}

_, err := u.SaveUser()
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"data": err.Error(),
})
return
}
c.JSON(http.StatusOK, gin.H{
"message": "register success",
"data":    req,
})
}

重新运行服务端后,客户端测试

$ curl -X POST http://127.0.0.1:8000/api/register -d '{"username": "zhangsan", "password": "123456"}' -H 'Content-Type=application/json'

{"data":{"username":"zhangsan","password":"123456"},"message":"register success"}

添加login接口

登录接口实现的也非常简单,只需要提供用户名和密码参数。服务端接收到客户端的请求后到数据库中去匹配,确认用户是否存在和密码是否正确。如果验证通过则返回一个token,否则返回异常响应。

首先在main.go中注册API

// xxx
func main() {
// xxx
r := gin.Default()
public := r.Group("/api")
{
public.POST("/register", controllers.Register)
public.POST("/login", controllers.Login)
}
}

auth.go中添加Login控制器函数

// api/login 的请求体
type ReqLogin struct {
Username string `json:"username" binding:"required"`
Password string `json:"password" binding:"required"`
}

func Login(c *gin.Context) {
var req ReqLogin
if err := c.ShouldBindBodyWithJSON(&req); err != nil {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
return
}

u := models.User{
Username: req.Username,
Password: req.Password,
}

// 调用 models.LoginCheck 对用户名和密码进行验证
token, err := models.LoginCheck(u.Username, u.Password)
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"error": "username or password is incorrect.",
})
return
}
c.JSON(http.StatusOK, gin.H{
"token": token,
})
}

LoginCheck方法在models/user.go文件中实现

package models

import (
"gin-jwt/utils/token"
"html"
"strings"

"golang.org/x/crypto/bcrypt"
"gorm.io/gorm"
)

func VerifyPassword(password, hashedPassword string) error {
return bcrypt.CompareHashAndPassword([]byte(hashedPassword), []byte(password))
}


func LoginCheck(username, password string) (string, error) {
var err error
u := User{}

err = DB.Model(User{}).Where("username = ?", username).Take(&u).Error
if err != nil {
return "", err
}
err = VerifyPassword(password, u.Password)
if err != nil && err == bcrypt.ErrMismatchedHashAndPassword {
return "", err
}

token, err := token.GenerateToken(u.ID)
if err != nil {
return "", err
}
return token, nil
}

这里将token相关的函数放到了单独的模块中,新增相关目录并编辑文件

mkdir -p utils/token
touch utils/token/token.go

以下代码为token.go的内容,包含的几个函数在后面会用到

package token

import (
"fmt"
"os"
"strconv"
"strings"
"time"

"github.com/gin-gonic/gin"
"github.com/golang-jwt/jwt/v5"
)

func GenerateToken(user_id uint) (string, error) {
token_lifespan, err := strconv.Atoi(os.Getenv("TOKEN_HOUR_LIFESPAN"))
if err != nil {
return "", err
}

claims := jwt.MapClaims{}
claims["authorized"] = true
claims["user_id"] = user_id
claims["exp"] = time.Now().Add(time.Hour * time.Duration(token_lifespan)).Unix()
token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)

return token.SignedString([]byte(os.Getenv("API_SECRET")))
}

func TokenValid(c *gin.Context) error {
tokenString := ExtractToken(c)
fmt.Println(tokenString)
_, err := jwt.Parse(tokenString, func(token *jwt.Token) (any, error) {
if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
}
return []byte(os.Getenv("API_SECRET")), nil
})
if err != nil {
return err
}

return nil
}

// 从请求头中获取token
func ExtractToken(c *gin.Context) string {
bearerToken := c.GetHeader("Authorization")
if len(strings.Split(bearerToken, " ")) == 2 {
return strings.Split(bearerToken, " ")[1]
}
return ""
}

// 从jwt中解析出user_id
func ExtractTokenID(c *gin.Context) (uint, error) {
tokenString := ExtractToken(c)
token, err := jwt.Parse(tokenString, func(token *jwt.Token) (any, error) {
if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
}
return []byte(os.Getenv("API_SECRET")), nil
})
if err != nil {
return 0, err
}
claims, ok := token.Claims.(jwt.MapClaims)
// 如果jwt有效,将user_id转换为浮点数字符串,然后再转换为 uint32
if ok && token.Valid {
uid, err := strconv.ParseUint(fmt.Sprintf("%.0f", claims["user_id"]), 10, 32)
if err != nil {
return 0, err
}
return uint(uid), nil
}

return 0, nil
}

.env文件中添加两个环境变量的配置。TOKEN_HOUR_LIFESPAN设置token的过期时长,API_SECRET是jwt的密钥。

TOKEN_HOUR_LIFESPAN=1
API_SECRET="wP3-sN6&gG4-lV8>gJ9)"

测试,这里改用python代码进行测试

import requests
import json

headers = {
    "Content-Type": "application/json",
}

resp = requests.get("http://127.0.0.1:8000/api/admin/user", headers=headers)

def register(username: str, password: str):
    req_body = {
        "username": username,
        "password": password,
    }
    resp = requests.post("http://127.0.0.1:8000/api/register", data=json.dumps(req_body), headers=headers)
    print(resp.text)

def login(username: str, password: str):
    req_body = {
        "username": username,
        "password": password,
    }
    resp = requests.post("http://127.0.0.1:8000/api/login", data=json.dumps(req_body), headers=headers)
    print(resp.text)
    if resp.status_code == 200:
        return resp.json()["token"]
    else:
        return ""

if __name__ == "__main__":
    username = "lisi"
    password = "123456"
    register(username, password)
    token = login(username, password)
print(token)

创建JWT认证中间件

创建中间件目录和代码文件

mkdir middlewares
touch middlewares/middlewares.go

内容如下

package middlewares

import (
"gin-jwt/utils/token"
"net/http"

"github.com/gin-gonic/gin"
)

func JwtAuthMiddleware() gin.HandlerFunc {
return func(c *gin.Context) {
err := token.TokenValid(c)
if err != nil {
c.String(http.StatusUnauthorized, err.Error())
c.Abort()
return
}
c.Next()
}
}

main.go文件中注册路由的时候使用中间件

func main() {
models.ConnectDatabase()
r := gin.Default()
public := r.Group("/api")
{
public.POST("/register", controllers.Register)
public.POST("/login", controllers.Login)
}

protected := r.Group("/api/admin")
{
protected.Use(middlewares.JwtAuthMiddleware())
protected.GET("/user", func(c *gin.Context) {
c.JSON(http.StatusOK, gin.H{
"status":  "success",
"message": "authorized",
})
})
}

r.Run("0.0.0.0:8000")
}

controllers/auth.go文件中实现CurrentUser

func CurrentUser(c *gin.Context) {
// 从token中解析出user_id
user_id, err := token.ExtractTokenID(c)
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"error": err.Error(),
})
return
}

// 根据user_id从数据库查询数据
u, err := models.GetUserByID(user_id)
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"error": err.Error(),
})
return
}

c.JSON(http.StatusOK, gin.H{
"message": "success",
"data": u,
})
}

models/user.go文件中实现GetUserByID

// 返回前将用户密码置空
func (u *User) PrepareGive() {
u.Password = ""
}

func GetUserByID(uid uint) (User, error) {
var u User
if err := DB.First(&u, uid).Error; err != nil {
return u, errors.New("user not found")
}

u.PrepareGive()
return u, nil
}

至此,一个简单的gin-jwt应用就完成了。

客户端测试python脚本

服务端的三个接口这里用python脚本来测试

import requests
import json

headers = {
    # "Authorization": f"Bearer {token}",
    "Content-Type": "application/json",
}

resp = requests.get("http://127.0.0.1:8000/api/admin/user", headers=headers)

def register(username: str, password: str):
    req_body = {
        "username": username,
        "password": password,
    }
    resp = requests.post("http://127.0.0.1:8000/api/register", data=json.dumps(req_body), headers=headers)
    print(resp.text)

def login(username: str, password: str):
    req_body = {
        "username": username,
        "password": password,
    }
    resp = requests.post("http://127.0.0.1:8000/api/login", data=json.dumps(req_body), headers=headers)
    print(resp.text)
    if resp.status_code == 200:
        return resp.json()["token"]
    else:
        return ""

def test_protect_api(token: str):
    global headers
    headers["Authorization"] = f"Bearer {token}"

    resp = requests.get("http://127.0.0.1:8000/api/admin/user", headers=headers)
    print(resp.text)

if __name__ == "__main__":
    username = "lisi"
    password = "123456"
    register(username, password)
    token = login(username, password)
    test_protect_api(token)

运行脚本结果

{"message":"register success"}
{"token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJhdXRob3JpemVkIjp0cnVlLCJleHAiOjE3MTk5NDA0NjAsInVzZXJfaWQiOjZ9.qkzn0Ot9hAb54l3RFbGUohHJ9oezGia5x_oXppbD2jQ"}
{"data":{"ID":6,"CreatedAt":"2024-07-03T00:14:20.187725+08:00","UpdatedAt":"2024-07-03T00:14:20.187725+08:00","DeletedAt":null,"username":"wangwu","password":""},"message":"success"}

完整示例代码

目录结构

├── client.py  # 客户端测试脚本
├── controllers  # 控制器相关包
│   └── auth.go  # 控制器方法实现
├── gin-jwt.bin  # 编译的二进制文件
├── go.mod  # go 项目文件
├── go.sum  # go 项目文件
├── main.go  # 程序入口文件
├── middlewares  # 中间件相关包
│   └── middlewares.go  # 中间件代码文件
├── models  # 存储层相关包
│   ├── setup.go  # 配置数据库连接
│   └── user.go  # user模块相关数据交互的代码文件
├── README.md  # git repo的描述文件
└── utils  # 工具类包
    └── token  # token相关工具类包
        └── token.go  # token工具的代码文件

main.go

package main

import (
"log"

"github.com/gin-gonic/gin"

"gin-jwt/controllers"
"gin-jwt/middlewares"
"gin-jwt/models"

"github.com/joho/godotenv"
)

func init() {
err := godotenv.Load(".env")
if err != nil {
log.Fatalf("Error loading .env file. %v\n", err)
}
}

func main() {
models.ConnectDatabase()
r := gin.Default()
public := r.Group("/api")
{
public.POST("/register", controllers.Register)
public.POST("/login", controllers.Login)
}

protected := r.Group("/api/admin")
{
protected.Use(middlewares.JwtAuthMiddleware()) // 在路由组中使用中间件
protected.GET("/user", controllers.CurrentUser)
}

r.Run("0.0.0.0:8000")
}

controllers

  • auth.go
package controllers

import (
"net/http"

"gin-jwt/models"
"gin-jwt/utils/token"

"github.com/gin-gonic/gin"
)

// /api/register的请求体
type ReqRegister struct {
Username string `json:"username" binding:"required"`
Password string `json:"password" binding:"required"`
}

// api/login 的请求体
type ReqLogin struct {
Username string `json:"username" binding:"required"`
Password string `json:"password" binding:"required"`
}

func Login(c *gin.Context) {
var req ReqLogin
if err := c.ShouldBindBodyWithJSON(&req); err != nil {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
return
}

u := models.User{
Username: req.Username,
Password: req.Password,
}

// 调用 models.LoginCheck 对用户名和密码进行验证
token, err := models.LoginCheck(u.Username, u.Password)
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"error": "username or password is incorrect.",
})
return
}
c.JSON(http.StatusOK, gin.H{
"token": token,
})
}

func Register(c *gin.Context) {
var req ReqRegister

if err := c.ShouldBindBodyWithJSON(&req); err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"data": err.Error(),
})
return
}

u := models.User{
Username: req.Username,
Password: req.Password,
}

_, err := u.SaveUser()
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"data": err.Error(),
})
return
}
c.JSON(http.StatusOK, gin.H{
"message": "register success",
})
}


func CurrentUser(c *gin.Context) {
// 从token中解析出user_id
user_id, err := token.ExtractTokenID(c)
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"error": err.Error(),
})
return
}

// 根据user_id从数据库查询数据
u, err := models.GetUserByID(user_id)
if err != nil {
c.JSON(http.StatusBadRequest, gin.H{
"error": err.Error(),
})
return
}

c.JSON(http.StatusOK, gin.H{
"message": "success",
"data": u,
})
}

models

  • setup.go
package models

import (
"fmt"
"log"
"os"

"gorm.io/driver/postgres"
"gorm.io/gorm"
)

var DB *gorm.DB

func ConnectDatabase() {
var err error
DbHost := os.Getenv("DB_HOST")
DbPort := os.Getenv("DB_PORT")
DbUser := os.Getenv("DB_USER")
DbPass := os.Getenv("DB_PASS")
DbName := os.Getenv("DB_NAME")

dsn := fmt.Sprintf("host=%s port=%s user=%s dbname=%s sslmode=disable TimeZone=Asia/Shanghai password=%s", DbHost, DbPort, DbUser, DbName, DbPass)

DB, err = gorm.Open(postgres.Open(dsn), &gorm.Config{})
if err != nil {
log.Fatalf("Connect to database failed, %v\n", err)
} else {
log.Printf("Connect to database success, host: %s, port: %s, user: %s, dbname: %s\n", DbHost, DbPort, DbUser, DbName)
}

// 迁移数据表
DB.AutoMigrate(&User{})
}
  • user.go
package models

import (
"errors"
"gin-jwt/utils/token"
"html"
"strings"

"golang.org/x/crypto/bcrypt"
"gorm.io/gorm"
)

type User struct {
gorm.Model
Username string `gorm:"size:255;not null;unique" json:"username"`
Password string `gorm:"size:255;not null;" json:"password"`
}

func (u *User) SaveUser() (*User, error) {
err := DB.Create(&u).Error
if err != nil {
return &User{}, err
}
return u, nil
}

// 使用gorm的hook在保存密码前对密码进行hash
func (u *User) BeforeSave(tx *gorm.DB) error {
hashedPassword, err := bcrypt.GenerateFromPassword([]byte(u.Password), bcrypt.DefaultCost)
if err != nil {
return err
}
u.Password = string(hashedPassword)
u.Username = html.EscapeString(strings.TrimSpace(u.Username))
return nil
}

// 返回前将用户密码置空
func (u *User) PrepareGive() {
u.Password = ""
}

// 对哈希加密的密码进行比对校验
func VerifyPassword(password, hashedPassword string) error {
return bcrypt.CompareHashAndPassword([]byte(hashedPassword), []byte(password))
}


func LoginCheck(username, password string) (string, error) {
var err error
u := User{}

err = DB.Model(User{}).Where("username = ?", username).Take(&u).Error
if err != nil {
return "", err
}
err = VerifyPassword(password, u.Password)
if err != nil && err == bcrypt.ErrMismatchedHashAndPassword {
return "", err
}

token, err := token.GenerateToken(u.ID)
if err != nil {
return "", err
}
return token, nil
}

func GetUserByID(uid uint) (User, error) {
var u User
if err := DB.First(&u, uid).Error; err != nil {
return u, errors.New("user not found")
}

u.PrepareGive()
return u, nil
}

utils

  • token/token.go
package token

import (
"fmt"
"os"
"strconv"
"strings"
"time"

"github.com/gin-gonic/gin"
"github.com/golang-jwt/jwt/v5"
)

func GenerateToken(user_id uint) (string, error) {
token_lifespan, err := strconv.Atoi(os.Getenv("TOKEN_HOUR_LIFESPAN"))
if err != nil {
return "", err
}

claims := jwt.MapClaims{}
claims["authorized"] = true
claims["user_id"] = user_id
claims["exp"] = time.Now().Add(time.Hour * time.Duration(token_lifespan)).Unix()
token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)

return token.SignedString([]byte(os.Getenv("API_SECRET")))
}

func TokenValid(c *gin.Context) error {
tokenString := ExtractToken(c)
fmt.Println(tokenString)
_, err := jwt.Parse(tokenString, func(token *jwt.Token) (any, error) {
if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
}
return []byte(os.Getenv("API_SECRET")), nil
})
if err != nil {
return err
}

return nil
}

// 从请求头中获取token
func ExtractToken(c *gin.Context) string {
bearerToken := c.GetHeader("Authorization")
if len(strings.Split(bearerToken, " ")) == 2 {
return strings.Split(bearerToken, " ")[1]
}
return ""
}

// 从jwt中解析出user_id
func ExtractTokenID(c *gin.Context) (uint, error) {
tokenString := ExtractToken(c)
token, err := jwt.Parse(tokenString, func(token *jwt.Token) (any, error) {
if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
}
return []byte(os.Getenv("API_SECRET")), nil
})
if err != nil {
return 0, err
}
claims, ok := token.Claims.(jwt.MapClaims)
// 如果jwt有效,将user_id转换为浮点数字符串,然后再转换为 uint32
if ok && token.Valid {
uid, err := strconv.ParseUint(fmt.Sprintf("%.0f", claims["user_id"]), 10, 32)
if err != nil {
return 0, err
}
return uint(uid), nil
}

return 0, nil
}

middlewares

  • middlewares.go
package middlewares

import (
"gin-jwt/utils/token"
"net/http"

"github.com/gin-gonic/gin"
)

func JwtAuthMiddleware() gin.HandlerFunc {
return func(c *gin.Context) {
err := token.TokenValid(c)
if err != nil {
c.String(http.StatusUnauthorized, err.Error())
c.Abort()
return
}
c.Next()
}
}

参考