feat: #2848 Server Session pattern (#2909)

* #2848 Moved project from private project directory to forked repo

* #2848 Requested changes implemented

server-session/src/test/java/com.iluwatar.sessionserver/LogoutHandlerTest.java

@@ -0,0 +1,75 @@
+import com.sun.net.httpserver.Headers;
+import com.sun.net.httpserver.HttpExchange;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import com.iluwatar.sessionserver.LogoutHandler;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.time.Instant;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.mockito.Mockito.when;
+
+public class LogoutHandlerTest {
+
+    private LogoutHandler logoutHandler;
+    private Headers headers;
+    private Map<String, Integer> sessions;
+    private Map<String, Instant> sessionCreationTimes;
+
+    @Mock
+    private HttpExchange exchange;
+
+    @BeforeEach
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        sessions = new HashMap<>();
+        sessionCreationTimes = new HashMap<>();
+        logoutHandler = new LogoutHandler(sessions, sessionCreationTimes);
+        headers = new Headers();
+        headers.add("Cookie", "sessionID=1234"); //Exchange object methods return Header Object but Exchange is mocked so Headers must be manually created
+    }
+
+    @Test
+    public void testHandler_SessionNotExpired() throws IOException {
+
+        //assemble
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        sessions.put("1234", 1); //Fake login details since LoginHandler isn't called
+        sessionCreationTimes.put("1234", Instant.now()); //Fake login details since LoginHandler isn't called
+        when(exchange.getRequestHeaders()).thenReturn(headers);
+        when(exchange.getResponseBody()).thenReturn(outputStream);
+
+        //act
+        logoutHandler.handle(exchange);
+
+        //assert
+        String[] response = outputStream.toString().split("Session ID: ");
+        Assertions.assertEquals("1234", response[1]);
+        Assertions.assertFalse(sessions.containsKey(response));
+        Assertions.assertFalse(sessionCreationTimes.containsKey(response));
+    }
+
+    @Test
+    public void testHandler_SessionExpired() throws IOException {
+
+        //assemble
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        when(exchange.getRequestHeaders()).thenReturn(headers);
+        when(exchange.getResponseBody()).thenReturn(outputStream);
+
+        //act
+        logoutHandler.handle(exchange);
+
+        //assert
+        String[] response = outputStream.toString().split("Session ID: ");
+        Assertions.assertEquals("Session has already expired!", response[0]);
+        Assertions.assertFalse(sessions.containsKey(response));
+        Assertions.assertFalse(sessionCreationTimes.containsKey(response));
+    }
+}