Adds tests for InternalSubject

Signed-off-by: Darshit Chanpura <[email protected]>

sandbox/libs/authn/src/test/java/org/opensearch/authn/internal/InternalSubjectTests.java

@@ -0,0 +1,111 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.authn.internal;
+
+import com.carrotsearch.randomizedtesting.annotations.ThreadLeakScope;
+import org.apache.shiro.SecurityUtils;
+import org.apache.shiro.authc.AuthenticationException;
+import org.apache.shiro.subject.Subject;
+import org.junit.After;
+import org.junit.Before;
+import org.opensearch.authn.AuthenticationManager;
+import org.opensearch.authn.tokens.AuthenticationToken;
+import org.opensearch.authn.tokens.BasicAuthToken;
+import org.opensearch.identity.Identity;
+import org.opensearch.test.OpenSearchTestCase;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ThreadLeakScope(ThreadLeakScope.Scope.NONE)
+public class InternalSubjectTests extends OpenSearchTestCase {
+    private static final AuthenticationToken AUTH_TOKEN = new BasicAuthToken("Basic YWRtaW46YWRtaW4=");
+
+    @Before
+    public void initRealm() {
+        final AuthenticationManager authManager = new InternalAuthenticationManager();
+        Identity.setAuthManager(authManager);
+    }
+
+    @After
+    public void logoutSubject() {
+        Subject subject = SecurityUtils.getSubject();
+        if (subject == null) return;
+        if (subject.getSession() != null) subject.getSession().stop();
+        SecurityUtils.getSubject().logout();
+    }
+
+    public void testGetPrincipal() {
+        InternalSubject internalSubject = new InternalSubject(SecurityUtils.getSubject());
+        assertNull(internalSubject.getPrincipal());
+
+        internalSubject.login(AUTH_TOKEN);
+
+        assertNotNull(internalSubject.getPrincipal());
+    }
+
+    public void testLoginBehaviors() {
+        Subject subject = mock(Subject.class);
+        InternalSubject internalSubject = new InternalSubject(subject);
+
+        // 1. Verify that login() is called on first attempt
+
+        internalSubject.login(AUTH_TOKEN);
+        verify(subject, times(1)).login(any());
+
+        // 2. Verify that call to login() is skipped on 2nd attempt for same user
+
+        when(subject.isAuthenticated()).thenReturn(true);
+        when(subject.getPrincipal()).thenReturn("admin");
+
+        internalSubject.login(AUTH_TOKEN);
+        verify(subject, times(1)).login(any());
+
+        // 3. Verify that login() is called again for a different user
+
+        when(subject.isAuthenticated()).thenReturn(true);
+        when(subject.getPrincipal()).thenReturn("marvin");
+
+        // even though we are using same token, the mock stub returns different principal and hence login is called again
+        internalSubject.login(AUTH_TOKEN);
+        verify(subject, times(2)).login(any());
+    }
+
+    public void testSuccessfulLoginAndLogOut() {
+        InternalSubject internalSubject = new InternalSubject(SecurityUtils.getSubject());
+
+        internalSubject.login(AUTH_TOKEN);
+        assertTrue(internalSubject.isAuthenticated());
+
+        internalSubject.logout();
+        assertFalse(internalSubject.isAuthenticated());
+
+        // subsequent logout calls for same user does not fail
+        internalSubject.logout();
+    }
+
+    public void testLoginFailure() {
+        InternalSubject internalSubject = new InternalSubject(SecurityUtils.getSubject());
+
+        AuthenticationToken authToken = new BasicAuthToken("Basic bWFydmluOmdhbGF4eQ==");
+
+        assertThrows(AuthenticationException.class, () -> internalSubject.login(authToken));
+    }
+
+    public void testIsAuthenticated() {
+        InternalSubject internalSubject = new InternalSubject(SecurityUtils.getSubject());
+
+        assertFalse(internalSubject.isAuthenticated());
+        internalSubject.login(AUTH_TOKEN);
+        assertTrue(internalSubject.isAuthenticated());
+    }
+}