Proxy to external URLs

gateway/src/main/java/org/georchestra/gateway/filter/headers/AddSecHeadersGatewayFilterFactory.java

@@ -36,6 +36,8 @@
 public class AddSecHeadersGatewayFilterFactory
         extends AbstractGatewayFilterFactory<AbstractGatewayFilterFactory.NameConfig> {
 
+    public static String DISABLE_SECURITY_HEADERS = AddSecHeadersGatewayFilterFactory.class.getName()
+            + ".DISABLE_SECURITY_HEADERS";
     private final List<HeaderContributor> providers;
 
     public AddSecHeadersGatewayFilterFactory(List<HeaderContributor> providers) {
@@ -57,15 +59,18 @@ private static class AddSecHeadersGatewayFilter implements GatewayFilter, Ordere
         private final @NonNull List<HeaderContributor> providers;
 
         public @Override Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
-            ServerHttpRequest.Builder requestBuilder = exchange.getRequest().mutate();
+            if (exchange.getAttribute(DISABLE_SECURITY_HEADERS) == null) {
+                ServerHttpRequest.Builder requestBuilder = exchange.getRequest().mutate();
 
-            providers.stream()//
-                    .map(provider -> provider.prepare(exchange))//
-                    .forEach(requestBuilder::headers);
+                providers.stream()//
+                        .map(provider -> provider.prepare(exchange))//
+                        .forEach(requestBuilder::headers);
 
-            ServerHttpRequest request = requestBuilder.build();
-            ServerWebExchange updatedExchange = exchange.mutate().request(request).build();
-            return chain.filter(updatedExchange);
+                ServerHttpRequest request = requestBuilder.build();
+                ServerWebExchange updatedExchange = exchange.mutate().request(request).build();
+                return chain.filter(updatedExchange);
+            }
+            return chain.filter(exchange);
         }
 
         @Override

gateway/src/main/java/org/georchestra/gateway/filter/headers/HeaderFiltersConfiguration.java

@@ -53,6 +53,10 @@ public class HeaderFiltersConfiguration {
         return new CookieAffinityGatewayFilterFactory();
     }
 
+    public @Bean ProxyGatewayFilterFactory proxyGatewayFilterFactory() {
+        return new ProxyGatewayFilterFactory();
+    }
+
     public @Bean GeorchestraUserHeadersContributor userSecurityHeadersProvider() {
         return new GeorchestraUserHeadersContributor();
     }

gateway/src/main/java/org/georchestra/gateway/filter/headers/ProxyGatewayFilterFactory.java

@@ -0,0 +1,40 @@
+package org.georchestra.gateway.filter.headers;
+
+import org.springframework.cloud.gateway.filter.GatewayFilter;
+import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.cloud.gateway.route.Route;
+import org.springframework.cloud.gateway.support.ServerWebExchangeUtils;
+
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.List;
+
+public class ProxyGatewayFilterFactory extends AbstractGatewayFilterFactory<Object> {
+    public ProxyGatewayFilterFactory() {
+        super(Object.class);
+    }
+
+    @Override
+    public GatewayFilter apply(final Object config) {
+        return (exchange, chain) -> {
+            Route route = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);
+            ServerHttpRequest request = exchange.getRequest();
+            List<String> urls = request.getQueryParams().get("url");
+            if ((urls != null) && (urls.size() == 1)) {
+                try {
+                    request = exchange.getRequest().mutate().uri(new URI(urls.get(0))).build();
+
+                    Route newRoute = Route.async().id(route.getId()).uri(new URI(urls.get(0))).order(route.getOrder())
+                            .asyncPredicate(route.getPredicate()).build();
+
+                    exchange.getAttributes().put(AddSecHeadersGatewayFilterFactory.DISABLE_SECURITY_HEADERS, "true");
+                    exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR, newRoute);
+                    return chain.filter(exchange.mutate().request(request).build());
+                } catch (URISyntaxException e) {
+                }
+            }
+            return chain.filter(exchange);
+        };
+    }
+}