go-restful + JWT身份验证

Question

我正在尝试将JWT身份验证插入到一个用go-restful编写的非常简单的go服务中。

代码非常类似于：

package main

import (
    "github.com/emicklei/go-restful"
    "log"
    "net/http"
)

type User struct {
    Id, Name string
}

type UserList struct {
    Users []User
}

func getAllUsers(request *restful.Request, response *restful.Response) {
    log.Printf("getAllUsers")
    response.WriteEntity(UserList{[]User{{"42", "Gandalf"}, {"3.14", "Pi"}}})
}

func NewUserService() *restful.WebService {
    ws := new(restful.WebService)
    ws.
        Path("/users").
        Consumes(restful.MIME_XML, restful.MIME_JSON).
        Produces(restful.MIME_JSON, restful.MIME_XML)

    ws.Route(ws.GET("").To(getAllUsers))

    return ws
}


func main() {
    restful.Add(NewUserService())
    log.Printf("start listening on localhost:8080")
    log.Fatal(http.ListenAndServe(":8080", nil))
}

其中restful.Request是http.Request的包装器。

话虽如此，使用Auth0 jwt middleware也是可能的。

但作为一个戈朗新手，我有点迷失在管道的过程中。我知道我必须使用一个Filter函数，比如

ws.Filter(jwtAuthentication)

哪里

func jwtAuthentication(req *restful.Request, resp *restful.Response, chain *restful.FilterChain) {
    // Jwt Magic goes here \o
    chain.ProcessFilter(req, resp)
}

但是我不知道应该如何以及在哪里实例化JWT中间件。

Answer 1

下面是使用auth0/go-jwt-middleware实现过滤器的示例。在现实生活中，您可能希望避免每次都创建新的jwtMiddleware实例。

func jwtAuthentication(req *restful.Request, resp *restful.Response, chain *restful.FilterChain) {
    jwtMiddleware := jwtmiddleware.New(jwtmiddleware.Options{
        ValidationKeyGetter: func(token *jwt.Token) (interface{}, error) {
            return []byte("My Secret"), nil
        },
        SigningMethod: jwt.SigningMethodHS256,
    })

    if err := jwtMiddleware.CheckJWT(resp.ResponseWriter, req.Request); err != nil {
        logger.Errorf("Authentication error: %v", err)
    }
    chain.ProcessFilter(req, resp)
}

在过滤器之后，解析后的令牌将位于上下文中(auth0/go-jwt-middleware使用gorilla/context)。默认上下文键为user。

注意:当设置了JWTMiddleware.SigningMethod时，中间件验证令牌是否使用特定的签名算法进行了签名。

如果签名方法不是常量，则可以使用ValidationKeyGetter回调实现额外的检查。

重要的是要避免here描述的安全问题。

Answer 2

以下是生成令牌登录API和检查身份验证的JWT身份验证筛选器的示例

import (
  "os"
  "strings"
  "github.com/dgrijalva/jwt-go"
  "golang.org/x/crypto/bcrypt"
)

type Token struct {
  UserId   uint
  Username string
  jwt.StandardClaims
}

type Account struct {
  ID       uint
  Email    string
  Password string
  Token    string
}

func Login(request *restful.Request, response *restful.Response) {
  account := &Account{ID: 1, Email: "test@email.com" }
  // TODO - account should be pulled from database

  tk := &Token{ UserId: account.ID }
  token := jwt.NewWithClaims(jwt.GetSigningMethod("HS256"), tk)
  tokenString, _ := token.SignedString([]byte("JWT-SECRET-GOES-RIGHT-HERE"))
  account.Token = tokenString
  account.Password = ''
  response.WriteEntity(account)
}

func JwtAuthentication(req *restful.Request, resp *restful.Response, chain *restful.FilterChain) {
    tokenHeader := req.Request.HeaderParameter("Authorization")

    if tokenHeader == "" {
      resp.WriteErrorString(http.StatusForbidden, "Not Authorized")
      return
    }

    splitted := strings.Split(tokenHeader, " ")
    if len(splitted) != 2 {
      resp.WriteErrorString(http.StatusForbidden, "Not Authorized")
      return
    }

    tokenPart := splitted[1]
    tk := &Token{}

    token, err := jwt.ParseWithClaims(tokenPart, tk, func(token *jwt.Token) (interface{}, error) {
      return []byte("JWT-SECRET-GOES-RIGHT-HERE"), nil
    })

    if err != nil { //Malformed token, returns with http code 403 as usual
      resp.WriteErrorString(http.StatusForbidden, "Not Authorized")
      return
    }

    if !token.Valid { //Token is invalid, maybe not signed on this server
      resp.WriteErrorString(http.StatusForbidden, "Not Authorized")
      return
    }

    chain.ProcessFilter(req, resp)
}

然后应用过滤器

ws.Filter(JwtAuthentication)