Added unit tests for ForwardRoutingFilter (#411)

spring-cloud-gateway-core/src/test/java/org/springframework/cloud/gateway/filter/ForwardRoutingFilterTests.java

@@ -0,0 +1,112 @@
+package org.springframework.cloud.gateway.filter;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.springframework.core.Ordered;
+import org.springframework.mock.http.server.reactive.MockServerHttpRequest;
+import org.springframework.mock.web.server.MockServerWebExchange;
+import org.springframework.web.reactive.DispatcherHandler;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.util.UriComponentsBuilder;
+
+import java.net.URI;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.*;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_ALREADY_ROUTED_ATTR;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR;
+
+/**
+ * @author Arjun Curat
+ */
+
+@RunWith(MockitoJUnitRunner.class)
+public class ForwardRoutingFilterTests {
+
+	private ServerWebExchange exchange;
+
+	@Mock
+	private GatewayFilterChain chain;
+
+	@Mock
+	private DispatcherHandler dispatcherHandler;
+
+	@InjectMocks
+	private ForwardRoutingFilter forwardRoutingFilter;
+
+	@Before
+	public void setup() {
+		exchange = MockServerWebExchange.from(MockServerHttpRequest.get("localendpoint").build());
+	}
+
+	@Test
+	public void shouldNotFilterWhenGatewayRequestUrlSchemeIsNotForward() {
+		URI uri = UriComponentsBuilder.fromUriString("http://endpoint").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, uri);
+		forwardRoutingFilter.filter(exchange, chain);
+
+		verifyZeroInteractions(dispatcherHandler);
+		verify(chain).filter(exchange);
+		verifyNoMoreInteractions(chain);
+	}
+
+	@Test
+	public void shouldFilterWhenGatewayRequestUrlSchemeIsForward() {
+		URI uri = UriComponentsBuilder.fromUriString("forward://endpoint").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, uri);
+
+		assertThat(exchange.getAttributes().get(GATEWAY_ALREADY_ROUTED_ATTR)).isNull();
+
+		forwardRoutingFilter.filter(exchange, chain);
+
+		verifyNoMoreInteractions(chain);
+		verify(dispatcherHandler).handle(exchange);
+
+		assertThat(exchange.getAttributes().get(GATEWAY_ALREADY_ROUTED_ATTR)).isEqualTo(true);
+	}
+
+	@Test
+	public void shouldFilterAndKeepHostPathAsSpecified() {
+
+		URI uri = UriComponentsBuilder.fromUriString("forward://host/outage").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, uri);
+
+		ArgumentCaptor<ServerWebExchange> captor = ArgumentCaptor.forClass(ServerWebExchange.class);
+
+		forwardRoutingFilter.filter(exchange, chain);
+
+		verify(dispatcherHandler).handle(captor.capture());
+
+		ServerWebExchange webExchange = captor.getValue();
+
+		URI forwardedUrl = webExchange.getRequiredAttribute(GATEWAY_REQUEST_URL_ATTR);
+
+		assertThat(forwardedUrl).hasScheme("forward").hasHost("host").hasPath("/outage");
+
+	}
+
+
+	@Test
+	public void shouldNotFilterWhenGatewayRequestUrlSchemeIsForwardButAlreadyRouted() {
+		URI uri = UriComponentsBuilder.fromUriString("forward://host").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, uri);
+		exchange.getAttributes().put(GATEWAY_ALREADY_ROUTED_ATTR, true);
+
+		forwardRoutingFilter.filter(exchange, chain);
+
+		verifyZeroInteractions(dispatcherHandler);
+		verify(chain).filter(exchange);
+		verifyNoMoreInteractions(chain);
+	}
+
+	@Test
+	public void orderIsLowestPrecedence() {
+		assertThat(forwardRoutingFilter.getOrder()).isEqualTo(Ordered.LOWEST_PRECEDENCE);
+	}
+
+}