Matt/header forwarding

gateway/src/main/java/com/mx/path/gateway/connect/filter/HeaderForwarderFilter.java

@@ -0,0 +1,30 @@
+package com.mx.path.gateway.connect.filter;
+
+import com.mx.path.core.common.connect.Request;
+import com.mx.path.core.common.connect.RequestFilterBase;
+import com.mx.path.core.common.connect.Response;
+import com.mx.path.core.context.RequestContext;
+import com.mx.path.core.context.UpstreamRequestConfiguration;
+
+/**
+ * Request Filter that adds forwarded headers to request
+ */
+public class HeaderForwarderFilter extends RequestFilterBase {
+
+  @Override
+  public final void execute(Request request, Response response) {
+    UpstreamRequestConfiguration upstreamRequestConfiguration = null;
+
+    if (RequestContext.current() != null) {
+      upstreamRequestConfiguration = RequestContext.current().getUpstreamRequestConfiguration();
+    }
+
+    if (upstreamRequestConfiguration != null && upstreamRequestConfiguration.getForwardedRequestHeaders() != null) {
+      upstreamRequestConfiguration.getForwardedRequestHeaders().forEach((key, value) -> {
+        request.withHeader(key, value.toString());
+      });
+    }
+
+    next(request, response);
+  }
+}

gateway/src/test/groovy/com/mx/path/gateway/connect/filter/HeaderForwarderFilterTest.groovy

@@ -0,0 +1,49 @@
+package com.mx.path.gateway.connect.filter
+
+import static org.mockito.Mockito.mock
+
+import com.mx.path.core.common.connect.Request
+import com.mx.path.core.common.connect.RequestFilter
+import com.mx.path.core.common.connect.Response
+import com.mx.path.core.context.RequestContext
+import com.mx.path.core.context.UpstreamRequestConfiguration
+
+import spock.lang.Specification
+
+class HeaderForwarderFilterTest extends Specification {
+  class TestRequest extends Request<TestRequest, TestResponse> {
+    TestRequest(RequestFilter filterChain) {
+      super(filterChain)
+    }
+
+    @Override
+    TestResponse execute() {
+      return null
+    }
+  }
+
+  class TestResponse extends Response<TestRequest, TestResponse> {
+  }
+
+  def "forwards all headers in current RequestContext forwardedHeader"() {
+    given:
+    def requestFilter = mock(RequestFilter)
+    def subject = new HeaderForwarderFilter()
+    def request = new TestRequest(requestFilter)
+    def response = new TestResponse()
+    RequestContext.builder()
+        .upstreamRequestConfiguration(UpstreamRequestConfiguration.builder()
+        .forwardedHeader("mx_forwarded_important_header", "12345")
+        .forwardedHeader("mx-forwarded-important-header", "12345")
+        .build())
+        .build()
+        .register()
+
+    when:
+    subject.execute(request, response)
+
+    then:
+    request.headers.containsKey("mx_forwarded_important_header")
+    request.headers.containsKey("mx-forwarded-important-header")
+  }
+}