Implementing Front‑Back End Separation with Spring Boot, Vue, and Shiro: CORS Handling and Deployment

In a front‑back end separated architecture, the frontend is isolated from the backend and communicates solely through JSON APIs; the backend no longer returns HTML pages, only data.

Backend – Spring Boot

The controller returns JSON data via a POST endpoint:

@RequestMapping(value = "/add", method = RequestMethod.POST)
@ResponseBody
public JSONResult addClient(@RequestBody String param) {
    JSONObject jsonObject = JSON.parseObject(param);
    String task = jsonObject.getString("task");
    List
list = jsonObject.getJSONArray("attributes");
    List
attrList = new LinkedList<>(list);
    Client client = JSON.parseObject(jsonObject.getJSONObject("client").toJSONString(), new TypeReference
(){});
    clientService.addClient(client, task, attrList);
    return JSONResult.ok();
}

The POST request receives parameters via @RequestBody .

Frontend – Vue + ElementUI + Vue‑Router + Vuex + Axios + Webpack

The frontend stack references the official Vue guide and popular admin templates. Common issues include cross‑origin requests because the webpack dev server runs on a different port.

CORS Handling

Two solutions are presented:

When the backend is self‑developed, add a Spring interceptor to set the required CORS headers:

@Component
public class CommonInterceptor implements HandlerInterceptor {
    private final Logger logger = LoggerFactory.getLogger(this.getClass());
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        response.setHeader("Access-Control-Allow-Origin", "*");
        if (request.getMethod().equals("OPTIONS")) {
            response.addHeader("Access-Control-Allow-Methods", "GET,HEAD,POST,PUT,DELETE,TRACE,OPTIONS,PATCH");
            response.addHeader("Access-Control-Allow-Headers", "Content-Type, Accept, Authorization");
        }
        return true;
    }
}

When the backend is not under your control, a proxyTable can be configured in the webpack dev server (only for development).

Shiro Integration in a Front‑Back End Separated Project

Because pre‑flight OPTIONS requests do not carry the Authorization header, they fail Shiro authentication. A custom filter extending FormAuthenticationFilter is added to allow OPTIONS requests and to return a JSON error for unauthenticated access:

public class CORSAuthenticationFilter extends FormAuthenticationFilter {
    @Override
    public boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        if (request instanceof HttpServletRequest) {
            if (((HttpServletRequest) request).getMethod().toUpperCase().equals("OPTIONS")) {
                return true;
            }
        }
        return super.isAccessAllowed(request, response, mappedValue);
    }
    @Override
    protected boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletResponse res = (HttpServletResponse) response;
        res.setHeader("Access-Control-Allow-Origin", "*");
        res.setStatus(HttpServletResponse.SC_OK);
        res.setCharacterEncoding("UTF-8");
        PrintWriter writer = res.getWriter();
        Map
map = new HashMap<>();
        map.put("code", 702);
        map.put("msg", "未登录");
        writer.write(JSON.toJSONString(map));
        writer.close();
        return false;
    }
}

The Shiro configuration registers this filter and defines the filter chain:

@Configuration
public class ShiroConfig {
    @Bean
    public Realm realm() { return new DDRealm(); }
    @Bean
    public CacheManager cacheManager() { return new MemoryConstrainedCacheManager(); }
    @Bean
    public SimpleCookie rememberMeCookie() {
        SimpleCookie cookie = new SimpleCookie("rememberMe");
        cookie.setMaxAge(259200);
        return cookie;
    }
    @Bean
    public CookieRememberMeManager rememberMeManager() {
        CookieRememberMeManager manager = new CookieRememberMeManager();
        manager.setCookie(rememberMeCookie());
        manager.setCipherKey(Base64.decode("2AvVhdsgUs0FSA3SDFAdag=="));
        return manager;
    }
    @Bean
    public SecurityManager securityManager() {
        DefaultWebSecurityManager sm = new DefaultWebSecurityManager();
        sm.setRealm(realm());
        sm.setCacheManager(cacheManager());
        sm.setRememberMeManager(rememberMeManager());
        sm.setSessionManager(sessionManager());
        return sm;
    }
    @Bean
    public SessionManager sessionManager() { return new CustomSessionManager(); }
    @Bean(name = "shiroFilter")
    public ShiroFilterFactoryBean getShiroFilterFactoryBean(SecurityManager securityManager) {
        ShiroFilterFactoryBean shiroFilter = new ShiroFilterFactoryBean();
        shiroFilter.setSecurityManager(securityManager);
        Map
filterChainDefinitionMap = new LinkedHashMap<>();
        filterChainDefinitionMap.put("/", "anon");
        filterChainDefinitionMap.put("/static/**", "anon");
        filterChainDefinitionMap.put("/login/**", "anon");
        filterChainDefinitionMap.put("/**", "corsAuthenticationFilter");
        shiroFilter.setFilterChainDefinitionMap(filterChainDefinitionMap);
        Map
filterMap = new LinkedHashMap<>();
        filterMap.put("corsAuthenticationFilter", corsAuthenticationFilter());
        shiroFilter.setFilters(filterMap);
        return shiroFilter;
    }
    @Bean
    public CORSAuthenticationFilter corsAuthenticationFilter() { return new CORSAuthenticationFilter(); }
    // additional beans for lifecycle, advisors, etc.
}

A custom CustomSessionManager overrides getSessionId to read the session ID from the Authorization header and extends the default timeout:

public class CustomSessionManager extends DefaultWebSessionManager {
    private static final String AUTHORIZATION = "Authorization";
    private static final String REFERENCED_SESSION_ID_SOURCE = "Stateless request";
    public CustomSessionManager() {
        super();
        setGlobalSessionTimeout(DEFAULT_GLOBAL_SESSION_TIMEOUT * 48);
    }
    @Override
    protected Serializable getSessionId(ServletRequest request, ServletResponse response) {
        String sessionId = WebUtils.toHttp(request).getHeader(AUTHORIZATION);
        if (!StringUtils.isEmpty(sessionId)) {
            request.setAttribute(ShiroHttpServletRequest.REFERENCED_SESSION_ID_SOURCE, REFERENCED_SESSION_ID_SOURCE);
            request.setAttribute(ShiroHttpServletRequest.REFERENCED_SESSION_ID, sessionId);
            request.setAttribute(ShiroHttpServletRequest.REFERENCED_SESSION_ID_IS_VALID, Boolean.TRUE);
            return sessionId;
        } else {
            return super.getSessionId(request, response);
        }
    }
}

Deployment

Two deployment approaches are described:

Package the Vue project into static files ( npm run build ) and serve them from a Spring Boot controller, eliminating cross‑origin issues.

Run the frontend as a separate service (Tomcat, Nginx, Node.js), which re‑introduces CORS considerations.

Example controller for serving the index page:

@RequestMapping(value = {"/", "/index"}, method = RequestMethod.GET)
public String index() {
    return "/index";
}

Additional deployment challenges such as Nginx reverse‑proxy redirects from HTTPS to HTTP and handling unauthenticated requests without Shiro’s default redirect are also discussed.

The article concludes with a reminder that the presented solutions may need adjustments for specific projects.