一、Spring Security介绍

1、框架介绍

Spring 是一个非常流行和成功的 Java 应用开发框架。Spring Security 基于 Spring 框架，提供了一套 Web 应用安全性的完整解决方案。一般来说，Web 应用的安全性包括用户认证（Authentication*）和用户授权（Authorization） 两个部分。

（1）用户认证指的是：验证某个用户是否为系统中的合法主体，也就是说用户能否访问该系统。用户认证一般要求用户提供用户名和密码。系统通过校验用户名和密码来完成认证过程。

（2）用户授权指的是验证某个用户是否有权限执行某个操作。在一个系统中，不同用户所具有的权限是不同的。比如对一个文件来说，有的用户只能进行读取，而有的用户可以进行修改。一般来说，系统会为不同的用户分配不同的角色，而每个角色则对应一系列的权限。

Spring Security其实就是用filter，多请求的路径进行过滤。

（1）如果是基于Session，那么Spring-security会对cookie里的sessionid进行解析，找到服务器存储的sesion信息，然后判断当前用户是否符合请求的要求。

（2）如果是token，则是解析出token，然后将当前请求加入到Spring-security管理的权限信息中去

2、认证与授权实现思路

如果系统的模块众多，每个模块都需要就行授权与认证，所以我们选择基于token的形式进行授权与认证，用户根据用户名密码认证成功，然后获取当前用户角色的一系列权限值，并以用户名为key，权限列表为value的形式存入redis缓存中，根据用户名相关信息生成token返回，浏览器将token记录到cookie中，每次调用api接口都默认将token携带到header请求头中，Spring-security解析header头获取token信息，解析token获取当前用户名，根据用户名就可以从redis中获取权限列表，这样Spring-security就能够判断当前请求是否有权限访问

二、整合Spring Security

1、首先创建Spring Security相关的模块以及代码架构

2、在spring_security引入相关依赖

<dependencies>
    <dependency>
        <groupId>com.jiangxia</groupId>
        <artifactId>common_utils</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </dependency>
    <!-- Spring Security依赖 -->

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
    <dependency>
        <groupId>io.jsonwebtoken</groupId>
        <artifactId>jjwt</artifactId>
    </dependency>
</dependencies>
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3、在需要使用spring_security的模块中引入spring_security依赖

<dependency>
    <groupId>com.atguigu</groupId>
    <artifactId>spring_security</artifactId>
    <version>0.0.1-SNAPSHOT</version>
</dependency>
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4、核心代码说明

Spring Security的核心配置就是继承WebSecurityConfigurerAdapter并注解@EnableWebSecurity的配置。这个配置指明了用户名密码的处理方式、请求路径的开合、登录登出控制等和安全相关的配置。主要代码如下：

@Configuration
@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class TokenWebSecurityConfig extends WebSecurityConfigurerAdapter {
    private UserDetailsService userDetailsService;
    private TokenManager tokenManager;
    private DefaultPasswordEncoder defaultPasswordEncoder;
    private RedisTemplate redisTemplate;
    @Autowired
    public TokenWebSecurityConfig(UserDetailsService userDetailsService, DefaultPasswordEncoder defaultPasswordEncoder,TokenManager tokenManager, RedisTemplate redisTemplate) {
        this.userDetailsService = userDetailsService;
        this.defaultPasswordEncoder = defaultPasswordEncoder;
        this.tokenManager = tokenManager;
        this.redisTemplate = redisTemplate;
    }

    /**
     * 配置设置
     * @param http
     * @throws Exception
     */
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.exceptionHandling()
                .authenticationEntryPoint(new UnauthorizedEntryPoint())
                .and().csrf().disable()
                .authorizeRequests()
                .anyRequest().authenticated()
                .and().logout().logoutUrl("/admin/acl/index/logout")
                .addLogoutHandler(new TokenLogoutHandler(tokenManager,redisTemplate)).and().addFilter(new TokenLoginFilter(authenticationManager(), tokenManager, redisTemplate)).addFilter(new TokenAuthenticationFilter(authenticationManager(), tokenManager, redisTemplate)).httpBasic();
    }
    /**
     * 密码处理
     * @param auth
     * @throws Exception
     */
    @Override
    public void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService).passwordEncoder(defaultPasswordEncoder);
    }
    //配置哪些请求不拦截
    @Override
    public void configure(WebSecurity web) throws Exception {
        web.ignoring().antMatchers("/api/**",
                "/swagger-resources/**", "/webjars/**", "/v2/**", "/swagger-ui.html/**"
               );
    }
}
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创建认证授权相关的工具类:

1、密码处理的方法

@Component
public class DefaultPasswordEncoder implements PasswordEncoder {
    public DefaultPasswordEncoder() {
        this(-1);
    }
    /**
     * @param strength
     *            the log rounds to use, between 4 and 31
     */
    public DefaultPasswordEncoder(int strength) {
    }
    public String encode(CharSequence rawPassword) {
        return MD5.encrypt(rawPassword.toString());
    }
    public boolean matches(CharSequence rawPassword, String encodedPassword) {
        return encodedPassword.equals(MD5.encrypt(rawPassword.toString()));
    }
}
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2、token操作的工具类

@Component
public class TokenManager {
    private long tokenExpiration = 24*60*60*1000;
    private String tokenSignKey = "123456";
    public String createToken(String username) {
        String token = Jwts.builder().setSubject(username)
                .setExpiration(new Date(System.currentTimeMillis() + tokenExpiration))
                .signWith(SignatureAlgorithm.HS512, tokenSignKey).compressWith(CompressionCodecs.GZIP).compact();
        return token;
    }
    public String getUserFromToken(String token) {
        String user = Jwts.parser().setSigningKey(tokenSignKey).parseClaimsJws(token).getBody().getSubject();
        return user;
    }
    public void removeToken(String token) {
        //jwttoken无需删除，客户端扔掉即可。
    }
}
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3、退出登录实现类

/**
 * 
 * 登出业务逻辑类
 *
 */
public class TokenLogoutHandler implements LogoutHandler {
    private TokenManager tokenManager;
    private RedisTemplate redisTemplate;
    public TokenLogoutHandler(TokenManager tokenManager, RedisTemplate redisTemplate) {
        this.tokenManager = tokenManager;
        this.redisTemplate = redisTemplate;
    }
    @Override
    public void logout(HttpServletRequest request, HttpServletResponse response, Authentication authentication) {
        String token = request.getHeader("token");
        if (token != null) {
            tokenManager.removeToken(token);
            //清空当前用户缓存中的权限数据
            String userName = tokenManager.getUserFromToken(token);
            redisTemplate.delete(userName);
        }
        ResponseUtil.out(response, R.ok());
    }
}
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4、针对未授权的统一处理方式

public class UnauthorizedEntryPoint implements AuthenticationEntryPoint {
    @Override
    public void commence(HttpServletRequest request, HttpServletResponse response,
                         AuthenticationException authException) throws IOException, ServletException {
        ResponseUtil.out(response, R.error());
    }
}
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5、创建认证和授权的filter

/**
 * 
 * 登录过滤器，继承UsernamePasswordAuthenticationFilter，对用户名密码进行登录校验，认证
 * 
 */
public class TokenLoginFilter extends UsernamePasswordAuthenticationFilter {
    private AuthenticationManager authenticationManager;
    private TokenManager tokenManager;
    private RedisTemplate redisTemplate;
    public TokenLoginFilter(AuthenticationManager authenticationManager, TokenManager tokenManager, RedisTemplate redisTemplate) {
        this.authenticationManager = authenticationManager;
        this.tokenManager = tokenManager;
        this.redisTemplate = redisTemplate;
        this.setPostOnly(false);
        this.setRequiresAuthenticationRequestMatcher(new AntPathRequestMatcher("/admin/acl/login","POST"));
    }
    @Override
    public Authentication attemptAuthentication(HttpServletRequest req, HttpServletResponse res)
            throws AuthenticationException {
        try {
            User user = new ObjectMapper().readValue(req.getInputStream(), User.class);
            return authenticationManager.authenticate(new UsernamePasswordAuthenticationToken(user.getUsername(), user.getPassword(), new ArrayList<>()));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
    /**
     * 登录成功
     * @param req
     * @param res
     * @param chain
     * @param auth
     * @throws IOException
     * @throws ServletException
     */
    @Override
    protected void successfulAuthentication(HttpServletRequest req, HttpServletResponse res, FilterChain chain,
                            Authentication auth) throws IOException, ServletException {
        SecurityUser user = (SecurityUser) auth.getPrincipal();
        String token = tokenManager.createToken(user.getCurrentUserInfo().getUsername());
        redisTemplate.opsForValue().set(user.getCurrentUserInfo().getUsername(), user.getPermissionValueList());
        ResponseUtil.out(res, R.ok().data("token", token));
    }
    /**
     * 登录失败
     * @param request
     * @param response
     * @param e
     * @throws IOException
     * @throws ServletException
     */
    @Override
    protected void unsuccessfulAuthentication(HttpServletRequest request, HttpServletResponse response,
                                              AuthenticationException e) throws IOException, ServletException {
        ResponseUtil.out(response, R.error());
    }
}
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/**
 * 访问过滤器：授权filter
 * 
 */
public class TokenAuthenticationFilter extends BasicAuthenticationFilter {
    private TokenManager tokenManager;
    private RedisTemplate redisTemplate;
    public TokenAuthenticationFilter(AuthenticationManager authManager, TokenManager tokenManager,RedisTemplate redisTemplate) {
        super(authManager);
        this.tokenManager = tokenManager;
        this.redisTemplate = redisTemplate;
    }
    @Override
    protected void doFilterInternal(HttpServletRequest req, HttpServletResponse res, FilterChain chain)
            throws IOException, ServletException {
        logger.info("================="+req.getRequestURI());
        if(req.getRequestURI().indexOf("admin") == -1) {
            chain.doFilter(req, res);
            return;
        }
        UsernamePasswordAuthenticationToken authentication = null;
        try {
            authentication = getAuthentication(req);
        } catch (Exception e) {
            ResponseUtil.out(res, R.error());
        }
        if (authentication != null) {
            SecurityContextHolder.getContext().setAuthentication(authentication);
        } else {
            ResponseUtil.out(res, R.error());
        }
        chain.doFilter(req, res);
    }
    private UsernamePasswordAuthenticationToken getAuthentication(HttpServletRequest request) {
        // token置于header里
        String token = request.getHeader("token");
        if (token != null && !"".equals(token.trim())) {
            String userName = tokenManager.getUserFromToken(token);
            List<String> permissionValueList = (List<String>) redisTemplate.opsForValue().get(userName);
            Collection<GrantedAuthority> authorities = new ArrayList<>();
            for(String permissionValue : permissionValueList) {
                if(StringUtils.isEmpty(permissionValue)) continue;
                SimpleGrantedAuthority authority = new SimpleGrantedAuthority(permissionValue);
                authorities.add(authority);
            }
            if (!StringUtils.isEmpty(userName)) {
                return new UsernamePasswordAuthenticationToken(userName, token, authorities);
            }
            return null;
        }
        return null;
    }
}
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总结

以上就是关于在springboot中进行spring security的相关逻辑。spring security授权和认证的流程大致其实跟自定义拦截器进行权限拦截是一样的。认证的过程就是客户端用户登录，然后服务端将用户登录信息缓存起来，最后服务端将用户信息（基本信息、权限、token等）返回给客户端。授权的过程，首先客户端发起请求，携带token，服务端解析token，判断用户是否登录，再从缓存中查询用户的菜单，判断用户是否有权限请求菜单，最后返回数据给客户端。

SpringBoot系列：整合Spring Security