springCloud跨域訪問
轉自：http://blog.csdn.net/wangkang80/article/details/72829390
什麽是跨域?
假設你在http://xxx.com/test/下有一個js文件,從這個js裏發出一個ajax請求請求後端服務,按照如下情況判定:
解決方案：
1） JSONP :
動態添加一個<script>標簽，而script標簽的src屬性是沒有跨域的限制的。這樣說來，這種跨域方式其實與ajax XmlHttpRequest協議無關了,而缺點也很明顯,它只支持GET請求而不支持POST等其它類型的HTTP請求；它只支持跨域HTTP請求這種情況，不能解決不同域的兩個頁面之間如何進行JavaScript調用的問題
2） NGINX代理 :
通過一個代理服務器,將跨域的請求轉發,如:前端JS在http://www.demo.com/a.js,後端是http://www.abc.com/app/action,通過代理可將後端的地址轉換成http://www.demo/app/action,這樣,從前端發起的請求,就不存在跨域的情況了
3）CORS
然後CORS是支持所有類型的HTTP請求,並且也只是服務端進行設置即可,但是缺點就是老的瀏覽器不支持CORS(如:IE7,7,8,等)
什麽是CORS？
Cross-origin resource sharing(跨域資源共享),是一個W3C標準,它允許你向一個不同源的服務器發出XMLHttpRequest
CORS的響應頭
Access-Control-Allow-Origin : 必須的,允許的域名,如果設置*,則表示接受任何域名
Access-Control-Allow-Credentials : 非必須的,表示是否允許發送Cookie,註意,當設置為true的時候,客戶端的ajax請求,也需要將withCredentials屬性設置為true
Access-Control-Expose-Headers : 非必須的,表示客戶端能拿到的header,默認情況下XMLHttpRequest的getResponseHeader方法只能拿到幾個基本的header,如果有自定義的header要獲取的話,則需要設置此值
Access-Control-Request-Method : 必須的,表示CORS上會使用到那些HTTP方法
Access-Control-Request-Headers : 必須的,表示CORS上會有那些額外的的有信息
代碼實現：
@Component
public class SimpleCORSFilter implements Filter {
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
HttpServletResponse response = (HttpServletResponse) res;
response.setHeader("Access-Control-Allow-Origin", "*");
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers", "x-requested-with");
chain.doFilter(req, res);
}
public void init(FilterConfig filterConfig) {}
public void destroy() {}
}
完整代碼，詳見：https://www.tianmaying.com/tutorial/cross-origin-rest-service
也可以通過nginx配置CORS：
轉自：https://enable-cors.org/server_nginx.html
#
# Wide-open CORS config for nginx
#
location / {
if ($request_method = ‘OPTIONS‘) {
add_header ‘Access-Control-Allow-Origin‘ ‘*‘;
add_header ‘Access-Control-Allow-Methods‘ ‘GET, POST, OPTIONS‘;
#
# Custom headers and headers various browsers *should* be OK with but aren‘t
#
add_header ‘Access-Control-Allow-Headers‘ ‘DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range‘;
#
# Tell client that this pre-flight info is valid for 20 days
#
add_header ‘Access-Control-Max-Age‘ 1728000;
add_header ‘Content-Type‘ ‘text/plain; charset=utf-8‘;
add_header ‘Content-Length‘ 0;
return 204;
}
if ($request_method = ‘POST‘) {
add_header ‘Access-Control-Allow-Origin‘ ‘*‘;
add_header ‘Access-Control-Allow-Methods‘ ‘GET, POST, OPTIONS‘;
add_header ‘Access-Control-Allow-Headers‘ ‘DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range‘;
add_header ‘Access-Control-Expose-Headers‘ ‘DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range‘;
}
if ($request_method = ‘GET‘) {
add_header ‘Access-Control-Allow-Origin‘ ‘*‘;
add_header ‘Access-Control-Allow-Methods‘ ‘GET, POST, OPTIONS‘;
add_header ‘Access-Control-Allow-Headers‘ ‘DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range‘;
add_header ‘Access-Control-Expose-Headers‘ ‘DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range‘;
}
}
springCloud跨域訪問