获取'无法在grails Spring安全性休息中调用null对象上的方法loadUserByUsername（）'

Posted 2021-04-05

我一直在尝试从这里实施Facebook OAuth：http://alvarosanchez.github.io/grails-spring-security-rest/latest/docs/index.html#_delegating_authentication_to_oauth_providers

我能够集成OAuth并从Facebook获取访问令牌，但我遇到了实现自定义OAuthUserDetailsS​​ervice的问题。我创建了一个自定义服务：

FacebookOauthUserDetails.groovy

class FacebookOauthUserDetailsService implements OauthUserDetailsService{

@Delegate
UserDetailsService userDetailsService
UserDetailsChecker preAuthenticationChecks

@Override
OauthUser loadUserByUserProfile(CommonProfile userProfile, Collection<GrantedAuthority> defaultRoles) throws UsernameNotFoundException {
    UserDetails userDetails
    OauthUser oauthUser
    println("adss")
    try {
        println("Trying to fetch user details for user profile: ${userProfile}")
        userDetails = userDetailsService.loadUserByUsername(userProfile.id)
        log.debug("Checking user details with ${preAuthenticationChecks.class.name}")
        preAuthenticationChecks?.check(userDetails)
        Collection<GrantedAuthority> allRoles = userDetails.authorities + defaultRoles
        oauthUser = new OauthUser(userDetails.username, userDetails.password, allRoles, userProfile)
    } catch (UsernameNotFoundException unfe) {
        println("User not found. Creating a new one with default roles: ${defaultRoles}")
        oauthUser = new OauthUser(userProfile.id, 'N/A', defaultRoles, userProfile)
    }

    return oauthUser
}
}

官方文档提到，为了覆盖默认行为，需要在resources.groovy中使用bean名称oauthUserDetailsS​​ervice定义它。这就是我的resources.groovy文件的样子：

resources.groovy：

import hungr.FacebookOauthUserDetailsService
import hungr.UserPasswordEncoderListener

beans =
{
    userPasswordEncoderListener(UserPasswordEncoderListener)
    oauthUserDetailsService(FacebookOauthUserDetailsService)
}

我试图在这里引用这个doc如何定义一个bean：https://docs.grails.org/latest/guide/spring.html，但它对我来说也没有用。我究竟做错了什么？

答案

GrailsUserDetailsService的接口基本上位于org.springframework.security.core.userdetails包中。您可以在服务（类）中实现上述服务（接口）的loadUserByUsername方法并编写代码（实现）以获取所需的数据/用户详细信息，您可以将用户详细信息作为对象/列表/映射获得您想要的任何格式，你可以通过GORM finder方法通过给定的用户名找到数据并返回该数据。以下是示例示例，

服务代码：

class Your_service_name implements GrailsUserDetailsService {

      Map loadUserByUsername(String username) throws UsernameNotFoundException {
        Map userDetails = [:]
        User.withTransaction { status ->

        User user = User.findByUsername(username, ["readOnly": true])
        if (!user) throw new UsernameNotFoundException('User not found', username)
        // you can also return the whole user object here instead of map keep method return type as UserDetails  and return user object, you also return the user roles along with other details in Map.
        userDetails["username"] = user.username
        userDetails["emailAddress"] = user.emailAddress
        userDetails["userFullName"] = user.userFullName
        return userDetails
   }
}

现在，您可以在控制器中注入上述服务并调用以下方法，

class YourController{
  Your_service_name myService // injected above created service which contains the loadUserByUsername method implementation

  def getUserDetails(){
    Map userdetails = myService.loadUserByUsername("username_to_find")
    println userdetails
  }
}

您的resources.groovy将如下，

beans = {
    userDetailsService(Your_service_name)
}

注意：在此更改后清理并重新启动应用程序。