[과제] Standard Spring Task 3

# 과제 요구사항

## 1) JwtAuthenticationFilter를 UserDetails를 활용하는 방식으로 변경

### 변경 전

- `new UsernamePasswordAuthenticationToken(email, null, authorities)` 형태

### 변경 후

- JWT에서 subject(email) 추출
- `CustomUserDetailsService` 활용 후  아래와 같은 형태로 사용

```java
@GetMapping("/private")
public String privateApi(@AuthenticationPrincipal CustomUserDetails userDetails) {
    String userEmail = userDetails.getUsername();
    return "hello userEmail=" + userEmail;
}
```

 

https://github.com/MinWoo1995/spring-security-prac

GitHub - MinWoo1995/spring-security-prac

 

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