Bael 9455 (#18863)

* BAEL-9455

* BAEL-9455

Author: Neetika23

spring-boot-modules/spring-boot-mvc-5/src/main/java/com/baeldung/hostport/GetHostPort.java

@@ -0,0 +1,45 @@
+package com.baeldung.hostport;
+
+import jakarta.servlet.http.HttpServletRequest;
+import org.springframework.web.servlet.support.ServletUriComponentsBuilder;
+
+public class GetHostPort {
+
+    public static String getHostWithPort(HttpServletRequest request) {
+        String scheme = request.getScheme();
+        String serverName = request.getServerName();
+        int serverPort = request.getServerPort();
+
+        boolean isDefaultPort = ("http".equals(scheme) && serverPort == 80)
+                || ("https".equals(scheme) && serverPort == 443);
+
+        if (isDefaultPort) {
+            return String.format("%s://%s", scheme, serverName);
+        } else {
+            return String.format("%s://%s:%d", scheme, serverName, serverPort);
+        }
+    }
+
+    public static String getBaseUrl() {
+        return ServletUriComponentsBuilder.fromCurrentRequestUri()
+                .replacePath(null)
+                .build()
+                .toUriString();
+    }
+
+    public static String getForwardedHost(HttpServletRequest request) {
+        String forwardedHost = request.getHeader("X-Forwarded-Host");
+        String forwardedProto = request.getHeader("X-Forwarded-Proto");
+        String forwardedPort = request.getHeader("X-Forwarded-Port");
+
+        String scheme = forwardedProto != null ? forwardedProto : request.getScheme();
+        String host = forwardedHost != null ? forwardedHost : request.getServerName();
+        String port = forwardedPort != null ? forwardedPort : String.valueOf(request.getServerPort());
+
+        boolean isDefaultPort = ("http".equals(scheme) && "80".equals(port))
+                || ("https".equals(scheme) && "443".equals(port));
+
+        return isDefaultPort ? String.format("%s://%s", scheme, host)
+                : String.format("%s://%s:%s", scheme, host, port);
+    }
+}

spring-boot-modules/spring-boot-mvc-5/src/test/java/com/baeldung/hostport/GetHostPortUnitTest.java

@@ -0,0 +1,117 @@
+package com.baeldung.hostport;
+
+import jakarta.servlet.http.HttpServletRequest;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+import org.springframework.mock.web.MockHttpServletRequest;
+import org.springframework.web.context.request.RequestContextHolder;
+import org.springframework.web.context.request.ServletRequestAttributes;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class GetHostPortUnitTest {
+
+    @Test
+    void givenHttpWithDefaultPort_whenGetHostWithPort_thenReturnWithoutPort() {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getScheme()).thenReturn("http");
+        Mockito.when(request.getServerName()).thenReturn("example.com");
+        Mockito.when(request.getServerPort()).thenReturn(80);
+
+        String result = GetHostPort.getHostWithPort(request);
+
+        assertEquals("http://example.com", result);
+    }
+
+    @Test
+    void givenHttpsWithDefaultPort_whenGetHostWithPort_thenReturnWithoutPort() {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getScheme()).thenReturn("https");
+        Mockito.when(request.getServerName()).thenReturn("secure.example.com");
+        Mockito.when(request.getServerPort()).thenReturn(443);
+
+        String result = GetHostPort.getHostWithPort(request);
+
+        assertEquals("https://secure.example.com", result);
+    }
+
+    @Test
+    void givenHttpWithCustomPort_whenGetHostWithPort_thenIncludePort() {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getScheme()).thenReturn("http");
+        Mockito.when(request.getServerName()).thenReturn("localhost");
+        Mockito.when(request.getServerPort()).thenReturn(8080);
+
+        String result = GetHostPort.getHostWithPort(request);
+
+        assertEquals("http://localhost:8080", result);
+    }
+
+    @Test
+    void givenHttpsWithCustomPort_whenGetHostWithPort_thenIncludePort() {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getScheme()).thenReturn("https");
+        Mockito.when(request.getServerName()).thenReturn("test.example.com");
+        Mockito.when(request.getServerPort()).thenReturn(8443);
+
+        String result = GetHostPort.getHostWithPort(request);
+
+        assertEquals("https://test.example.com:8443", result);
+    }
+
+    @Test
+    void whenUsingServletUriComponentsBuilder_thenReturnBaseUrl() {
+        MockHttpServletRequest request = new MockHttpServletRequest();
+        request.setScheme("https");
+        request.setServerName("example.com");
+        request.setServerPort(8443);
+        request.setRequestURI("/api/users/123");
+
+        RequestContextHolder.setRequestAttributes(new ServletRequestAttributes(request));
+        String baseUrl = GetHostPort.getBaseUrl();
+
+        assertEquals("https://example.com:8443", baseUrl);
+
+        RequestContextHolder.resetRequestAttributes();
+    }
+
+    @Test
+    void givenRequestURL_whenParse_thenExtractHostWithPort() throws MalformedURLException {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getRequestURL()).thenReturn(new StringBuffer("http://localhost:8080/api/test"));
+
+        URL url = new URL(request.getRequestURL().toString());
+        String hostWithPort = url.getPort() == -1
+                ? String.format("%s://%s", url.getProtocol(), url.getHost())
+                : String.format("%s://%s:%d", url.getProtocol(), url.getHost(), url.getPort());
+
+        assertEquals("http://localhost:8080", hostWithPort);
+    }
+
+    @Test
+    void givenForwardedHeaders_whenGetForwardedHost_thenReturnProxyHost() {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getHeader("X-Forwarded-Host")).thenReturn("proxy.example.com");
+        Mockito.when(request.getHeader("X-Forwarded-Proto")).thenReturn("https");
+        Mockito.when(request.getHeader("X-Forwarded-Port")).thenReturn("443");
+
+        String result = GetHostPort.getForwardedHost(request);
+
+        assertEquals("https://proxy.example.com", result);
+    }
+
+    @Test
+    void givenNoForwardedHeaders_whenGetForwardedHost_thenUseRequestValues() {
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        Mockito.when(request.getScheme()).thenReturn("http");
+        Mockito.when(request.getServerName()).thenReturn("localhost");
+        Mockito.when(request.getServerPort()).thenReturn(8080);
+
+        String result = GetHostPort.getForwardedHost(request);
+
+        assertEquals("http://localhost:8080", result);
+    }
+}