add: CrossOriginFilter

Author: wendal

src/org/nutz/mvc/filter/CrossOriginFilter.java

@@ -0,0 +1,54 @@
+package org.nutz.mvc.filter;
+
+import org.nutz.lang.Strings;
+import org.nutz.log.Log;
+import org.nutz.log.Logs;
+import org.nutz.mvc.ActionContext;
+import org.nutz.mvc.ActionFilter;
+import org.nutz.mvc.View;
+import org.nutz.mvc.view.HttpServerResponse;
+import org.nutz.mvc.view.VoidView;
+
+import javax.servlet.http.HttpServletResponse;
+
+/**
+ * 如果是OPTIONS请求，那么返回自定义的Access-Control-Allow-*头部
+ */
+public class CrossOriginFilter implements ActionFilter {
+
+    private static final Log log = Logs.get();
+
+    protected String origin;
+    protected String methods;
+    protected String headers;
+    protected String credentials;
+
+    public CrossOriginFilter() {
+        this("*", "get, post, put, delete, options", "origin, content-type, accept", "true");
+    }
+
+    public CrossOriginFilter(String origin, String methods, String headers, String credentials) {
+        this.origin = origin;
+        this.methods = methods;
+        this.headers = headers;
+        this.credentials = credentials;
+    }
+
+    public View match(ActionContext ac) {
+        if ("OPTIONS".equals(ac.getRequest().getMethod())) {
+            if (log.isDebugEnabled())
+                log.debugf("Feedback -- [%s] [%s] [%s] [%s]", origin, methods, headers, credentials);
+            HttpServletResponse resp = ac.getResponse();
+            if (!Strings.isBlank(origin))
+                resp.addHeader("Access-Control-Allow-Origin", origin);
+            if (!Strings.isBlank(methods))
+                resp.addHeader("Access-Control-Allow-Methods", methods);
+            if (!Strings.isBlank(headers))
+                resp.addHeader("Access-Control-Allow-Headers", headers);
+            if (!Strings.isBlank(credentials))
+                resp.addHeader("Access-Control-Allow-Credentials", credentials);
+            return new VoidView();
+        }
+        return null;
+    }
+}