#New: Add OPTIONS Method for All Java WebServices (REST + API Objects). Add "Allow" Headers + CORS Headers.

Author: ggallotti

wrappercommon/src/main/java/com/genexus/cors/CORSHelper.java

@@ -11,23 +11,25 @@ public class CORSHelper {
 	private static String CORS_ALLOWED_HEADERS = "*";
 
 	public static HashMap<String, String> getCORSHeaders(String requestRequiredHeaders) {
+		return getCORSHeaders(requestRequiredHeaders, CORS_ALLOWED_METHODS);
+	}
+	public static HashMap<String, String> getCORSHeaders(String requestRequiredHeaders, String allowedMethods) {
 		String corsAllowedOrigin = SpecificImplementation.Application.getClientPreferences().getProperty(CORS_ALLOWED_ORIGIN, "");
-		if (corsAllowedOrigin == null || corsAllowedOrigin.isEmpty()) {
+		if (corsAllowedOrigin == null || corsAllowedOrigin.isEmpty() || allowedMethods.isEmpty()) {
 			return null;
 		}
+
 		HashMap<String, String> corsHeaders = new HashMap<>();
 		corsHeaders.put(
 			"Access-Control-Allow-Origin", corsAllowedOrigin);
 		corsHeaders.put(
 			"Access-Control-Allow-Credentials", "true");
-
 		corsHeaders.put(
 			"Access-Control-Allow-Headers",
 			requestRequiredHeaders == null || requestRequiredHeaders.isEmpty() ? CORS_ALLOWED_HEADERS : requestRequiredHeaders);
-
 		corsHeaders.put(
 			"Access-Control-Allow-Methods",
-			CORS_ALLOWED_METHODS);
+			allowedMethods);
 		corsHeaders.put(
 			"Access-Control-Max-Age",
 			CORS_MAX_AGE_SECONDS);

wrapperjakarta/src/main/java/com/genexus/ws/JAXRSCorsFilter.java

@@ -1,5 +1,10 @@
 package com.genexus.ws.rs.core;
 
+import com.genexus.cors.CORSHelper;
+import com.genexus.servlet.http.IHttpServletRequest;
+
+import java.util.HashMap;
+
 public abstract class Response extends jakarta.ws.rs.core.Response{
 
 	public static Response.ResponseBuilder notModifiedWrapped() {
@@ -14,6 +19,24 @@ public static Response.ResponseBuilder okWrapped() {
 		return new Response.ResponseBuilder(jakarta.ws.rs.core.Response.ok());
 	}
 
+	public static Response.ResponseBuilder options(String allowedMethods) {
+		Response.ResponseBuilder builder = okWrapped();
+		builder.header("Allow", allowedMethods);
+		return builder;
+	}
+
+	private static void addCorsHeaders(IHttpServletRequest request, IResponseBuilder builder) {
+		HashMap<String, String> corsHeaders = CORSHelper.getCORSHeaders(request.getHeader("Access-Control-Request-Headers"), request.getMethod());
+		for (String headerName : corsHeaders.keySet()) {
+			builder.header(headerName,corsHeaders.get(headerName));
+		}
+	}
+
+	public static jakarta.ws.rs.core.Response build(IHttpServletRequest request, IResponseBuilder builder) {
+		addCorsHeaders(request, builder);
+		return (jakarta.ws.rs.core.Response)builder.build();
+	}
+
 	public static Response.ResponseBuilder notFound() {
 		return new Response.ResponseBuilder(jakarta.ws.rs.core.Response.status(Status.NOT_FOUND));
 	}

wrapperjakarta/src/main/java/com/genexus/ws/rs/core/Response.java

@@ -1,5 +1,10 @@
 package com.genexus.ws.rs.core;
 
+import com.genexus.cors.CORSHelper;
+import com.genexus.servlet.http.IHttpServletRequest;
+
+import java.util.HashMap;
+
 public abstract class Response extends javax.ws.rs.core.Response{
 
 	public static Response.ResponseBuilder notModifiedWrapped() {
@@ -13,6 +18,25 @@ public static Response.ResponseBuilder okWrapped(Object entity) {
 	public static Response.ResponseBuilder okWrapped() {
 		return new Response.ResponseBuilder(javax.ws.rs.core.Response.ok());
 	}
+
+	public static Response.ResponseBuilder options(String allowedMethods) {
+		Response.ResponseBuilder builder = new Response.ResponseBuilder(javax.ws.rs.core.Response.ok());
+		builder.header("Allow", allowedMethods);
+		return builder;
+	}
+
+	private static void addCorsHeaders(IHttpServletRequest request, IResponseBuilder builder) {
+		HashMap<String, String> corsHeaders = CORSHelper.getCORSHeaders(request.getHeader("Access-Control-Request-Headers"), request.getMethod());
+		for (String headerName : corsHeaders.keySet()) {
+			builder.header(headerName,corsHeaders.get(headerName));
+		}
+	}
+
+	public static javax.ws.rs.core.Response build(IHttpServletRequest request, IResponseBuilder builder) {
+		addCorsHeaders(request, builder);
+		return (javax.ws.rs.core.Response)builder.build();
+	}
+
 	public static Response.ResponseBuilder notFound() {
 		return new Response.ResponseBuilder(javax.ws.rs.core.Response.status(Status.NOT_FOUND));
 	}