Add CORS

CAu_NLP_2019/src/main/java/com/nlp/App.java

@@ -11,8 +11,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
-import static spark.Spark.get;
-import static spark.Spark.port;
+import static spark.Spark.*;
 
 public class App {
 
@@ -24,6 +23,27 @@ public class App {
             ArrayList<Result> results = getResults(words);
             return gson.toJson(results);
         });
+        options("/*",
+                (request, response) -> {
+
+                    String accessControlRequestHeaders = request
+                            .headers("Access-Control-Request-Headers");
+                    if (accessControlRequestHeaders != null) {
+                        response.header("Access-Control-Allow-Headers",
+                                accessControlRequestHeaders);
+                    }
+
+                    String accessControlRequestMethod = request
+                            .headers("Access-Control-Request-Method");
+                    if (accessControlRequestMethod != null) {
+                        response.header("Access-Control-Allow-Methods",
+                                accessControlRequestMethod);
+                    }
+
+                    return "OK";
+                });
+
+        before((request, response) -> response.header("Access-Control-Allow-Origin", "*"));
     }
 
     private static ArrayList<Result> getResults(String[] words) throws Exception {