AuthenticationPrincipalArgumentResolver (spring-security-messaging 5.6.8 API)

java.lang.Object
- org.springframework.security.messaging.handler.invocation.reactive.AuthenticationPrincipalArgumentResolver

All Implemented Interfaces:

org.springframework.messaging.handler.invocation.reactive.HandlerMethodArgumentResolver
```
public class AuthenticationPrincipalArgumentResolver
extends java.lang.Object
implements org.springframework.messaging.handler.invocation.reactive.HandlerMethodArgumentResolver
```
Allows resolving the Authentication.getPrincipal() using the AuthenticationPrincipal annotation. For example, the following Controller:
```
 @Controller
 public class MyController {
     @MessageMapping("/im")
     public void im(@AuthenticationPrincipal CustomUser customUser) {
         // do something with CustomUser
     }
 }
 
```
Will resolve the CustomUser argument using Authentication.getPrincipal() from the ReactiveSecurityContextHolder. If the Authentication or Authentication.getPrincipal() is null, it will return null. If the types do not match, null will be returned unless AuthenticationPrincipal.errorOnInvalidType() is true in which case a ClassCastException will be thrown.
Alternatively, users can create a custom meta annotation as shown below:
```
 @Target({ ElementType.PARAMETER })
 @Retention(RetentionPolicy.RUNTIME)
 @AuthenticationPrincipal
 public @interface CurrentUser {
 }
 
```
The custom annotation can then be used instead. For example:
```
 @Controller
 public class MyController {
     @MessageMapping("/im")
     public void im(@CurrentUser CustomUser customUser) {
         // do something with CustomUser
     }
 }
 
```
Since:

5.2

Constructor Summary

Constructors
Constructor Description

AuthenticationPrincipalArgumentResolver()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`reactor.core.publisher.Mono<java.lang.Object>`	`resolveArgument(org.springframework.core.MethodParameter parameter, org.springframework.messaging.Message<?> message)`
`void`	`setAdapterRegistry(org.springframework.core.ReactiveAdapterRegistry adapterRegistry)`	Sets the `ReactiveAdapterRegistry` to be used.
`void`	`setBeanResolver(org.springframework.expression.BeanResolver beanResolver)`	Sets the `BeanResolver` to be used on the expressions
`boolean`	`supportsParameter(org.springframework.core.MethodParameter parameter)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - AuthenticationPrincipalArgumentResolver
```
public AuthenticationPrincipalArgumentResolver()
```
- Method Detail
  - setBeanResolver
```
public void setBeanResolver(org.springframework.expression.BeanResolver beanResolver)
```
    Sets the BeanResolver to be used on the expressions
    
    Parameters:
    
    beanResolver - the BeanResolver to use
  - setAdapterRegistry
```
public void setAdapterRegistry(org.springframework.core.ReactiveAdapterRegistry adapterRegistry)
```
    Sets the ReactiveAdapterRegistry to be used.
    
    Parameters:
    
    adapterRegistry - the ReactiveAdapterRegistry to use. Cannot be null. Default is ReactiveAdapterRegistry.getSharedInstance()
  - supportsParameter
```
public boolean supportsParameter(org.springframework.core.MethodParameter parameter)
```
    Specified by:
    
    supportsParameter in interface org.springframework.messaging.handler.invocation.reactive.HandlerMethodArgumentResolver
  - resolveArgument
```
public reactor.core.publisher.Mono<java.lang.Object> resolveArgument(org.springframework.core.MethodParameter parameter,
                                                                     org.springframework.messaging.Message<?> message)
```
    Specified by:
    
    resolveArgument in interface org.springframework.messaging.handler.invocation.reactive.HandlerMethodArgumentResolver