给一个 jwt 的例子
时间: 2023-06-29 10:19:27 浏览: 81
好的,以下是一个 JWT 的例子:
```
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
```
这个 JWT 由三个部分组成,每个部分都由 . 分隔开来:
- 头部(Header):eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9
- 载荷(Payload):eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ
- 签名(Signature):SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
其中,头部和载荷都是经过 Base64 编码的 JSON 对象,签名则是用于验证 JWT 真实性的字符串。可以通过将头部和载荷进行 Base64 解码,再加上一个秘钥,使用指定的算法(例如 HS256)生成签名。在验证 JWT 时,可以使用相同的秘钥和算法,对头部和载荷进行 Base64 解码并生成签名,然后将生成的签名与 JWT 中的签名进行比较,如果一致说明 JWT 有效,否则 JWT 无效。
相关问题
给出一个springboot项目集成jwt的例子
好的,我可以回答这个问题。以下是一个Spring Boot项目集成JWT的示例:
1. 首先,需要在pom.xml文件中添加以下依赖:
```
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt</artifactId>
<version>.9.1</version>
</dependency>
```
2. 创建一个JwtUtil类,用于生成和验证JWT:
```
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
@Component
public class JwtUtil {
@Value("${jwt.secret}")
private String secret;
@Value("${jwt.expiration}")
private Long expiration;
public String generateToken(String username) {
Map<String, Object> claims = new HashMap<>();
claims.put("sub", username);
claims.put("created", new Date());
return Jwts.builder()
.setClaims(claims)
.setExpiration(new Date(System.currentTimeMillis() + expiration * 100))
.signWith(SignatureAlgorithm.HS512, secret)
.compact();
}
public boolean validateToken(String token, String username) {
Claims claims = getClaims(token);
if (claims != null) {
String subject = claims.getSubject();
Date expirationDate = claims.getExpiration();
Date now = new Date(System.currentTimeMillis());
if (subject.equals(username) && expirationDate.after(now)) {
return true;
}
}
return false;
}
public Claims getClaims(String token) {
try {
return Jwts.parser().setSigningKey(secret).parseClaimsJws(token).getBody();
} catch (Exception e) {
return null;
}
}
}
```
3. 创建一个JwtAuthenticationFilter类,用于拦截请求并验证JWT:
```
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
public class JwtAuthenticationFilter extends AbstractAuthenticationProcessingFilter {
public JwtAuthenticationFilter(AuthenticationManager authenticationManager) {
super(new AntPathRequestMatcher("/api/**"));
setAuthenticationManager(authenticationManager);
}
@Override
public Authentication attemptAuthentication(HttpServletRequest request, HttpServletResponse response) {
String token = request.getHeader("Authorization");
if (token != null) {
String username = JwtUtil.getClaims(token).getSubject();
if (username != null) {
return getAuthenticationManager().authenticate(new UsernamePasswordAuthenticationToken(username, null));
}
}
return null;
}
@Override
protected void successfulAuthentication(HttpServletRequest request, HttpServletResponse response, FilterChain chain, Authentication authResult) throws IOException, ServletException {
SecurityContextHolder.getContext().setAuthentication(authResult);
chain.doFilter(request, response);
}
}
```
4. 在WebSecurityConfig类中配置JwtAuthenticationFilter:
```
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
@Configuration
@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
@Autowired
private JwtAuthenticationEntryPoint jwtAuthenticationEntryPoint;
@Autowired
private JwtUserDetailsService jwtUserDetailsService;
@Autowired
private JwtRequestFilter jwtRequestFilter;
@Override
protected void configure(HttpSecurity http) throws Exception {
http.csrf().disable()
.authorizeRequests().antMatchers("/api/authenticate").permitAll()
.anyRequest().authenticated()
.and().exceptionHandling().authenticationEntryPoint(jwtAuthenticationEntryPoint)
.and().sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS);
http.addFilterBefore(jwtRequestFilter, UsernamePasswordAuthenticationFilter.class);
}
@Autowired
public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
auth.userDetailsService(jwtUserDetailsService).passwordEncoder(passwordEncoder());
}
@Bean
public PasswordEncoder passwordEncoder() {
return new BCryptPasswordEncoder();
}
@Bean
@Override
public AuthenticationManager authenticationManagerBean() throws Exception {
return super.authenticationManagerBean();
}
@Bean
public JwtAuthenticationFilter jwtAuthenticationFilter() throws Exception {
return new JwtAuthenticationFilter(authenticationManagerBean());
}
}
```
以上就是一个Spring Boot项目集成JWT的示例,希望能对你有所帮助。
flask_jwt_extended 生成token 写一个例子给我
好的,以下是一个使用 flask_jwt_extended 生成 token 的例子:
```python
from flask import Flask
from flask_jwt_extended import JWTManager, create_access_token
app = Flask(__name__)
app.config['JWT_SECRET_KEY'] = 'super-secret' # 设置 JWT 密钥
jwt = JWTManager(app)
@app.route('/login', methods=['POST'])
def login():
# 假设这里有一个验证用户身份的过程
user_id = '123'
access_token = create_access_token(identity=user_id) # 生成 token
return {'access_token': access_token}
if __name__ == '__main__':
app.run()
```
在这个例子中,我们首先创建了一个 Flask 应用,并设置了 JWT 密钥。然后,我们定义了一个 `/login` 路由,用于验证用户身份并生成 token。在 `create_access_token` 函数中,我们传入了一个 `identity` 参数,这个参数可以是任何标识用户身份的信息,比如用户 ID。最后,我们将生成的 token 返回给客户端。