首页 > 解决方案 > Spring boot AngularJs $http.get 为空

问题描述

我正在创建一个资源监视器,用于检索有关不同域但相同端口上的机器的典型信息。直接访问url时,数据返回成功。但是,如果我们使用 angularJs 尝试它,$http.get 请求将返回“被 CORS 策略阻止:请求的资源上不存在 'Access-Control-Allow-Origin' 标头”。我们决定使用 chrome CORS 扩展来允许连接。唯一的问题是尽管数据存在,但 $http.get 请求始终为空。不知道为什么会发生这种情况,因为没有产生错误。

角度控制器

app.controller("ServerResourcesController", [ "$scope", "$http", function($scope, $http) {

     $http.get("http://000.000.0.0:8080/testing")
    .then(function(data){
        console.log(data);
        })
}]);

控制器

@RestController
public class ServerRestController {

    Logger logger = LoggerFactory.getLogger(ServerRestController.class);
    ServerQueryController sqc = new ServerQueryController();

    @RequestMapping("/server-service-info")
    public String ServiceInfo() {//Welcome page, non-rest
        return "Server Resource Monitor Service";
    }

    //rest end point
    @GetMapping("/server-resources-info")
    public ServerInformation ServerInformation() {
        ServerInformation serverInformation = sqc.CurrentServerResourceInformation();
        return serverInformation;
    }
    }

项目等级

@Getter @Setter
@JsonIgnoreProperties(ignoreUnknown = true)
public class ServerInformation {

    private String name;
    private String ipAddress;
    private double systemCpuLoad;
    private double freePhysicalMemory;
    private double totalPhysicalMemory;
    private String operatingSystem;
    private double freeDiskSpace;
    private double diskUsage;

    public ServerInformation() {

    }

    @Override
    public String toString() {
        return "Values{ systemCpuLoad: "+systemCpuLoad+
                ", freePhysicalMemory: "+freePhysicalMemory+
                ", totalPhysicalMemory: "+totalPhysicalMemory+
                ", operatingSystem: "+operatingSystem+
                ", freeDiskSpace: "+freeDiskSpace+
                ", diskUsage: "+diskUsage+
                " }";
    }

}

标签: javaangularjshttp

解决方案


看来您ServerRestController需要跨域,添加此

@RestController
@CrossOrigin(origins = "*")
public class ServerRestController {
...
}

此外,如果你想允许一个特定的来源,你可以这样做:

@CrossOrigin(origins = "http://stackoverflow.com", maxAge = 3600)

您可以@CrossOrigin在每种方法或RestController.

此外,如果您有多个RestController,最好不要@CrossOrigin在每个控制器上编写,您可以创建一个Filter这样的:

@Component
public class SimpleCORSFilter implements Filter {

private final Logger log = LoggerFactory.getLogger(SimpleCORSFilter.class);

public SimpleCORSFilter() {
    log.info("SimpleCORSFilter init");
}

@Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;

response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));
response.setHeader("Access-Control-Allow-Credentials", "true");
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers", "Content-Type, Accept, X-Requested-With, remember-me");

chain.doFilter(req, res);
}

@Override
public void init(FilterConfig filterConfig) {
}

@Override
public void destroy() {
}

}

请参阅此处的示例:spring cors


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