Github oauth return error: The code passed is incorrect or expired

[xiaolin310]

After I do login, github returned a validate token, and When do login again , it raised an error The code passed is incorrect or expired

My code is as follows,

import (
    "context"
    "fmt"
    "github.com/gin-gonic/gin"
    "golang.org/x/oauth2"
    "golang.org/x/oauth2/github"
    "net/http"
)

var (
    oauthConf = &oauth2.Config{
        ClientID:     "your-client-id",
        ClientSecret: "your-client-secret",
        RedirectURL:  "http://localhost:8080/callback",
        Scopes:       []string{"user:email"},
        Endpoint:     github.Endpoint,
    }
)

func main() {
    r := gin.Default()

    r.GET("/", func(c *gin.Context) {
        html := "<a href='/login/github'>Login with GitHub</a>"
        c.HTML(http.StatusOK, "login.html", gin.H{"html": html})
    })

    r.GET("/login/github", func(c *gin.Context) {
        url := oauthConf.AuthCodeURL("state", oauth2.AccessTypeOffline)
        c.Redirect(http.StatusTemporaryRedirect, url)
    })

    r.GET("/callback", func(c *gin.Context) {
        code := c.Query("code")
        token, err := oauthConf.Exchange(context.Background(), code)
        if err != nil {
            c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
            return
        }

        client := oauthConf.Client(context.Background(), token)
        resp, err := client.Get("https://api.github.com/user/emails")
        if err != nil {
            c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
            return
        }
        defer resp.Body.Close()

        c.JSON(http.StatusOK, resp)
    })

    r.Run(":8080")
}

The error is traced to this line,

        url := oauthConf.AuthCodeURL("state", oauth2.AccessTypeOffline)