Spark CORS Access-control-allow-origin error - http

Question

I'm using Spark with Java and Angular 1 on client side.
I keep getting this '-1' error when I send request to the server.
The error is "No 'Access-control-allow-origin' header is present on the requested resource. Origin 'http://localhost:4567' is therefore not allowed access."
I understand it's a CORS issue so I add header 'Access-Control-Allow-Origin' : '*' and added it as well to the response on server side.
Unfortunately it doesn't seem to solve my problem.
Need your help guys,
Thanks!

Answer 1

Spark.after() is your friend
package com.company.package;
import static spark.Spark.*;
import com.google.gson.Gson;
import spark.Filter;
import spark.Request;
import spark.Response;
public class MyClass {
public static void main(String[] args) {
final Service service = new ServiceImpl();
after((Filter) (request, response) -> {
response.header("Access-Control-Allow-Origin", "*");
response.header("Access-Control-Allow-Methods", "GET");
});
get( "/something", (req, res)->{
res.type("application/json");
return new Gson().toJsonTree(service.getNodes());
});
}
}

Answer 2

I have used the following successfully (which I found here: https://gist.github.com/zikani03/7c82b34fbbc9a6187e9a):
//add correct package
import com.mpaw.app.controllers.Apply;
import java.util.HashMap;
import spark.Filter;
import spark.Request;
import spark.Response;
import spark.Spark;
/**
* Really simple helper for enabling CORS in a spark application;
*/
public class CorsFilter /*implements Apply*/{
private final HashMap<String, String> corsHeaders = new HashMap<>();
public CorsFilter() {
corsHeaders.put("Access-Control-Allow-Methods", "GET,PUT,POST,DELETE,OPTIONS");
corsHeaders.put("Access-Control-Allow-Origin", "*");
corsHeaders.put("Access-Control-Allow-Headers", "Content-Type,Authorization,X-Requested-With,Content-Length,Accept,Origin,");
corsHeaders.put("Access-Control-Allow-Credentials", "true");
}
#Override
public void apply() {
Filter filter = new Filter() {
#Override
public void handle(Request request, Response response) throws Exception {
corsHeaders.forEach((key, value) -> {
response.header(key, value);
});
}
};
Spark.after(filter);
}
}
Usage:
public static void main(String[] args) {
CorsFilter.apply(); // Call this before mapping thy routes
Spark.get("/hello", (request, response) -> {
return "Hello";
});
}