implement ui client session id

This changeset introduces a client side session id, which is generated
once by the client (ui: apiClient) and is send with each request to server.
The server makes the session id available by the PrincipalCollection of the
subject.

pom.xml

@@ -839,7 +839,7 @@
     <jaxb.version>2.3.0</jaxb.version>
 
     <!-- event bus -->
-    <legman.version>1.5.1</legman.version>
+    <legman.version>1.6.0</legman.version>
 
     <!-- webserver -->
     <jetty.version>9.4.22.v20191022</jetty.version>

scm-core/src/main/java/sonia/scm/security/BearerToken.java

@@ -37,6 +37,8 @@ import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
 import org.apache.shiro.authc.AuthenticationToken;
 
+import javax.annotation.Nullable;
+
 /**
  * Token used for authentication with bearer tokens.
  *
@@ -45,14 +47,17 @@ import org.apache.shiro.authc.AuthenticationToken;
  */
 public final class BearerToken implements AuthenticationToken {
 
+  private final SessionId sessionId;
   private final String raw;
 
   /**
    * Constructs a new instance.
    *
+   * @param sessionId session id of the client
    * @param raw raw bearer token
    */
-  private BearerToken(String raw) {
+  private BearerToken(SessionId sessionId, String raw) {
+    this.sessionId = sessionId;
     this.raw = raw;
   }
 
@@ -67,13 +72,13 @@ public final class BearerToken implements AuthenticationToken {
   }
 
   /**
-   * Returns always {@code null}.
+   * Returns the session id or {@code null}.
    *
-   * @return {@code null}
+   * @return session id or {@code null}
    */
   @Override
-  public Object getPrincipal() {
-    return null;
+  public SessionId getPrincipal() {
+    return sessionId;
   }
 
   /**
@@ -85,6 +90,23 @@ public final class BearerToken implements AuthenticationToken {
    */
   public static BearerToken valueOf(String raw){
     Preconditions.checkArgument(!Strings.isNullOrEmpty(raw), "raw token is required");
-    return new BearerToken(raw);
+    return new BearerToken(null, raw);
+  }
+
+  /**
+   * Creates a new {@link BearerToken} from raw string representation for the given ui session id.
+   *
+   * @param sessionId session id of the client
+   * @param rawToken bearer token string representation
+   *
+   * @return new bearer token
+   */
+  public static BearerToken create(@Nullable String sessionId, String rawToken) {
+    Preconditions.checkArgument(!Strings.isNullOrEmpty(rawToken), "raw token is required");
+    SessionId session = null;
+    if (!Strings.isNullOrEmpty(sessionId)) {
+      session = SessionId.valueOf(sessionId);
+    }
+    return new BearerToken(session, rawToken);
   }
 }

scm-core/src/main/java/sonia/scm/security/DAORealmHelper.java

@@ -115,7 +115,7 @@ public final class DAORealmHelper {
     UsernamePasswordToken upt = (UsernamePasswordToken) token;
     String principal = upt.getUsername();
 
-    return getAuthenticationInfo(principal, null, null);
+    return getAuthenticationInfo(principal, null, null, null);
   }
 
   /**
@@ -129,8 +129,9 @@ public final class DAORealmHelper {
     return new AuthenticationInfoBuilder(principal);
   }
 
-
-  private AuthenticationInfo getAuthenticationInfo(String principal, String credentials, Scope scope) {
+  private SimpleAuthenticationInfo getAuthenticationInfo(
+    String principal, String credentials, Scope scope, SessionId sessionId
+  ) {
     checkArgument(!Strings.isNullOrEmpty(principal), "username is required");
 
     LOG.debug("try to authenticate {}", principal);
@@ -150,6 +151,10 @@ public final class DAORealmHelper {
     collection.add(user, realm);
     collection.add(MoreObjects.firstNonNull(scope, Scope.empty()), realm);
 
+    if (sessionId != null) {
+      collection.add(sessionId, realm);
+    }
+
     String creds = credentials;
 
     if (credentials == null) {
@@ -170,7 +175,7 @@ public final class DAORealmHelper {
 
     private String credentials;
     private Scope scope;
-    private Iterable<String> groups = Collections.emptySet();
+    private SessionId sessionId;
 
     private AuthenticationInfoBuilder(String principal) {
       this.principal = principal;
@@ -201,17 +206,17 @@ public final class DAORealmHelper {
       return this;
     }
 
-//    /**
-//     * With groups adds extra groups, besides those which come from the {@link GroupDAO}, to the authentication info.
-//     *
-//     * @param groups extra groups
-//     *
-//     * @return {@code this}
-//     */
-//    public AuthenticationInfoBuilder withGroups(Iterable<String> groups) {
-//      this.groups = groups;
-//      return this;
-//    }
+    /**
+     * With the session id.
+     *
+     * @param sessionId session id
+     *
+     * @return {@code this}
+     */
+    public AuthenticationInfoBuilder withSessionId(SessionId sessionId) {
+      this.sessionId = sessionId;
+      return this;
+    }
 
     /**
      * Build creates the authentication info from the given information.
@@ -219,7 +224,7 @@ public final class DAORealmHelper {
      * @return authentication info
      */
     public AuthenticationInfo build() {
-      return getAuthenticationInfo(principal, credentials, scope);
+      return getAuthenticationInfo(principal, credentials, scope, sessionId);
     }
 
   }

scm-core/src/main/java/sonia/scm/security/SessionID.java

@@ -0,0 +1,41 @@
+package sonia.scm.security;
+
+import com.google.common.base.Preconditions;
+import com.google.common.base.Strings;
+
+import java.util.Objects;
+
+/**
+ * Client side session id.
+ */
+public final class SessionId {
+
+  private final String value;
+
+  private SessionId(String value) {
+    this.value = value;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    SessionId sessionID = (SessionId) o;
+    return Objects.equals(value, sessionID.value);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(value);
+  }
+
+  @Override
+  public String toString() {
+    return value;
+  }
+
+  public static SessionId valueOf(String value) {
+    Preconditions.checkArgument(!Strings.isNullOrEmpty(value), "session id could not be empty or null");
+    return new SessionId(value);
+  }
+}

scm-core/src/main/java/sonia/scm/util/HttpUtil.java

@@ -116,6 +116,12 @@ public final class HttpUtil
    */
   public static final String HEADER_SCM_CLIENT = "X-SCM-Client";
 
+  /**
+   * header for identifying the scm-manager client session
+   * @since 2.0.0
+   */
+  public static final String HEADER_SCM_SESSION = "X-SCM-Session-ID";
+
   /** Field description */
   public static final String HEADER_USERAGENT = "User-Agent";
 
@@ -698,8 +704,10 @@ public final class HttpUtil
     String defaultValue)
   {
     String value = request.getHeader(header);
-
-    return MoreObjects.firstNonNull(value, defaultValue);
+    if (value == null) {
+      value = defaultValue;
+    }
+    return value;
   }
 
   /**

scm-core/src/test/java/sonia/scm/security/DAORealmHelperTest.java

@@ -27,9 +27,6 @@ class DAORealmHelperTest {
   @Mock
   private UserDAO userDAO;
 
-  @Mock
-  private GroupDAO groupDAO;
-
   private DAORealmHelper helper;
 
   @BeforeEach
@@ -87,6 +84,21 @@ class DAORealmHelperTest {
     assertThat(principals.oneByType(Scope.class)).isSameAs(scope);
   }
 
+  @Test
+  void shouldReturnAuthenticationInfoWithSessionId() {
+    User user = new User("trillian");
+    when(userDAO.get("trillian")).thenReturn(user);
+
+    SessionId session = SessionId.valueOf("abc123");
+
+    AuthenticationInfo authenticationInfo = helper.authenticationInfoBuilder("trillian")
+      .withSessionId(session)
+      .build();
+
+    PrincipalCollection principals = authenticationInfo.getPrincipals();
+    assertThat(principals.oneByType(SessionId.class)).isSameAs(session);
+  }
+
   @Test
   void shouldReturnAuthenticationInfoWithCredentials() {
     User user = new User("trillian");

scm-core/src/test/java/sonia/scm/util/HttpUtilTest.java

@@ -54,6 +54,31 @@ import javax.servlet.http.HttpServletRequest;
 public class HttpUtilTest
 {
 
+  @Test
+  public void testGetHeader() {
+    HttpServletRequest request = mock(HttpServletRequest.class);
+    when(request.getHeader("Test")).thenReturn("Value-One");
+
+    String value = HttpUtil.getHeader(request, "Test", "Fallback");
+    assertEquals("Value-One", value);
+  }
+
+  @Test
+  public void testGetHeaderWithDefaultValue() {
+    HttpServletRequest request = mock(HttpServletRequest.class);
+
+    String value = HttpUtil.getHeader(request, "Test", "Fallback");
+    assertEquals("Fallback", value);
+  }
+
+  @Test
+  public void testGetHeaderWithNullAsDefaultValue() {
+    HttpServletRequest request = mock(HttpServletRequest.class);
+
+    String value = HttpUtil.getHeader(request, "Test", null);
+    assertNull(value);
+  }
+
   @Test
   public void concatenateTest() {
     assertEquals(

scm-ui/ui-components/src/apiclient.ts

@@ -2,12 +2,20 @@ import { contextPath } from "./urls";
 import { createBackendError, ForbiddenError, isBackendError, UnauthorizedError } from "./errors";
 import { BackendErrorContent } from "./errors";
 
+const sessionId = (
+  Date.now().toString(36) +
+  Math.random()
+    .toString(36)
+    .substr(2, 5)
+).toUpperCase();
+
 const applyFetchOptions: (p: RequestInit) => RequestInit = o => {
   o.credentials = "same-origin";
   o.headers = {
     Cache: "no-cache",
     // identify the request as ajax request
-    "X-Requested-With": "XMLHttpRequest"
+    "X-Requested-With": "XMLHttpRequest",
+    "X-SCM-Session-ID": sessionId
   };
   return o;
 };

scm-webapp/src/main/java/sonia/scm/security/BearerRealm.java

@@ -104,6 +104,7 @@ public class BearerRealm extends AuthenticatingRealm
     return helper.authenticationInfoBuilder(accessToken.getSubject())
       .withCredentials(bt.getCredentials())
       .withScope(Scopes.fromClaims(accessToken.getClaims()))
+      .withSessionId(bt.getPrincipal())
       .build();
   }
 

scm-webapp/src/main/java/sonia/scm/web/BearerWebTokenGenerator.java

@@ -70,7 +70,8 @@ public class BearerWebTokenGenerator extends SchemeBasedWebTokenGenerator
 
     if (HttpUtil.AUTHORIZATION_SCHEME_BEARER.equalsIgnoreCase(scheme))
     {
-      token = BearerToken.valueOf(authorization);
+      String sessionId = request.getHeader(HttpUtil.HEADER_SCM_SESSION);
+      token = BearerToken.create(sessionId, authorization);
     }
 
     return token;

scm-webapp/src/main/java/sonia/scm/web/CookieBearerWebTokenGenerator.java

@@ -43,7 +43,7 @@ import javax.servlet.http.HttpServletRequest;
 import sonia.scm.util.HttpUtil;
 
 /**
- * Creates an {@link BearerToken} from the {@link #COOKIE_NAME} 
+ * Creates an {@link BearerToken} from the {@link HttpUtil#COOKIE_BEARER_AUTHENTICATION}
  * cookie.
  *
  * @author Sebastian Sdorra
@@ -54,7 +54,7 @@ public class CookieBearerWebTokenGenerator implements WebTokenGenerator
 {
 
   /**
-   * Creates an {@link BearerToken} from the {@link #COOKIE_NAME} 
+   * Creates an {@link BearerToken} from the {@link HttpUtil#COOKIE_BEARER_AUTHENTICATION}
    * cookie.
    *
    * @param request http servlet request
@@ -73,7 +73,8 @@ public class CookieBearerWebTokenGenerator implements WebTokenGenerator
       {
         if (HttpUtil.COOKIE_BEARER_AUTHENTICATION.equals(cookie.getName()))
         {
-          token = BearerToken.valueOf(cookie.getValue());
+          String sessionId = HttpUtil.getHeader(request, HttpUtil.HEADER_SCM_SESSION, null);
+          token = BearerToken.create(sessionId, cookie.getValue());
 
           break;
         }

scm-webapp/src/main/java/sonia/scm/web/security/DefaultAdministrationContext.java

@@ -177,45 +177,26 @@ public class DefaultAdministrationContext implements AdministrationContext
     //J+
   }
 
-  /**
-   * Method description
-   *
-   *
-   * @param action
-   */
-  private void doRunAsInNonWebSessionContext(PrivilegedAction action)
-  {
-    if (logger.isTraceEnabled())
-    {
+  private void doRunAsInNonWebSessionContext(PrivilegedAction action) {
     logger.trace("bind shiro security manager to current thread");
-    }
 
-    try
-    {
+    try {
       SecurityUtils.setSecurityManager(securityManager);
 
       Subject subject = createAdminSubject();
       ThreadState state = new SubjectThreadState(subject);
 
       state.bind();
-
       try
       {
-        if (logger.isInfoEnabled())
-        {
-          logger.info("execute action {} in administration context",
-            action.getClass().getName());
-        }
+        logger.info("execute action {} in administration context", action.getClass().getName());
 
         action.run();
+      } finally {
+        logger.trace("restore current thread state");
+        state.restore();
       }
-      finally
-      {
-        state.clear();
-      }
-    }
-    finally
-    {
+    } finally {
       SecurityUtils.setSecurityManager(null);
     }
   }

scm-webapp/src/test/java/sonia/scm/security/BearerRealmTest.java

@@ -84,11 +84,9 @@ class BearerRealmTest {
 
   @Test
   void shouldDoGetAuthentication() {
-    BearerToken bearerToken = BearerToken.valueOf("__bearer__");
+    BearerToken bearerToken = BearerToken.create("__session__", "__bearer__");
     AccessToken accessToken = mock(AccessToken.class);
 
-    Set<String> groups = ImmutableSet.of("HeartOfGold", "Puzzle42");
-
     when(accessToken.getSubject()).thenReturn("trillian");
     when(accessToken.getClaims()).thenReturn(new HashMap<>());
     when(accessTokenResolver.resolve(bearerToken)).thenReturn(accessToken);
@@ -96,6 +94,7 @@ class BearerRealmTest {
     when(realmHelper.authenticationInfoBuilder("trillian")).thenReturn(builder);
     when(builder.withCredentials("__bearer__")).thenReturn(builder);
     when(builder.withScope(any(Scope.class))).thenReturn(builder);
+    when(builder.withSessionId(any(SessionId.class))).thenReturn(builder);
     when(builder.build()).thenReturn(authenticationInfo);
 
     AuthenticationInfo result = realm.doGetAuthenticationInfo(bearerToken);

scm-webapp/src/test/java/sonia/scm/web/BearerWebTokenGeneratorTest.java

@@ -33,47 +33,73 @@ package sonia.scm.web;
 
 import javax.servlet.http.HttpServletRequest;
 import org.apache.shiro.authc.AuthenticationToken;
-import org.junit.Test;
-import static org.junit.Assert.*;
-import static org.hamcrest.Matchers.*;
-import org.junit.runner.RunWith;
+
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
+
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.Mockito.*;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import sonia.scm.security.BearerToken;
+import sonia.scm.security.SessionId;
+import sonia.scm.util.HttpUtil;
 
 /**
  *
  * @author Sebastian Sdorra
  */
-@RunWith(MockitoJUnitRunner.class)
-public class BearerWebTokenGeneratorTest {
+@ExtendWith(MockitoExtension.class)
+class BearerWebTokenGeneratorTest {
+
+  private final BearerWebTokenGenerator tokenGenerator = new BearerWebTokenGenerator();
 
   @Mock
   private HttpServletRequest request;
 
-  private final BearerWebTokenGenerator tokenGenerator = new BearerWebTokenGenerator();
-
   @Test
-  public void testCreateTokenWithWrongScheme()
-  {
+  void shouldNotCreateTokenWithWrongScheme() {
     when(request.getHeader("Authorization")).thenReturn("BASIC ASD");
-    assertNull(tokenGenerator.createToken(request));
-  }
 
-  @Test
-  public void testCreateTokenWithoutAuthorizationHeader(){
-    assertNull(tokenGenerator.createToken(request));
-  }
-  
-  @Test
-  public void testCreateToken(){
-    when(request.getHeader("Authorization")).thenReturn("Bearer asd");
     AuthenticationToken token = tokenGenerator.createToken(request);
-    assertNotNull(token);
-    assertThat(token, instanceOf(BearerToken.class));
+
+    assertThat(token).isNull();
+  }
+
+  @Test
+  void shouldNotCreateTokenWithoutAuthorizationHeader(){
+    AuthenticationToken token = tokenGenerator.createToken(request);
+
+    assertThat(token).isNull();
+  }
+
+  @Test
+  void shouldCreateToken(){
+    when(request.getHeader("Authorization")).thenReturn("Bearer asd");
+
+    AuthenticationToken token = tokenGenerator.createToken(request);
+    assertThat(token)
+      .isNotNull()
+      .isInstanceOf(BearerToken.class);
+
     BearerToken bt = (BearerToken) token;
-    assertThat(bt.getCredentials(), equalTo("asd"));
+    assertThat(bt.getCredentials()).isEqualTo("asd");
+  }
+
+  @Test
+  void shouldCreateTokenWithSessionId(){
+    doReturn("Bearer asd").when(request).getHeader("Authorization");
+    doReturn("bcd123").when(request).getHeader(HttpUtil.HEADER_SCM_SESSION);
+
+    AuthenticationToken token = tokenGenerator.createToken(request);
+    assertThat(token)
+      .isNotNull()
+      .isInstanceOf(BearerToken.class);
+
+    BearerToken bt = (BearerToken) token;
+    assertThat(bt.getPrincipal()).isEqualTo(SessionId.valueOf("bcd123"));
+    assertThat(bt.getCredentials()).isEqualTo("asd");
   }
 
 }

scm-webapp/src/test/java/sonia/scm/web/CookieBearerWebTokenGeneratorTest.java

@@ -35,82 +35,81 @@ package sonia.scm.web;
 
 //~--- non-JDK imports --------------------------------------------------------
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
-
+import org.mockito.junit.jupiter.MockitoExtension;
 import sonia.scm.security.BearerToken;
-
-import static org.junit.Assert.*;
-
-import static org.mockito.Mockito.*;
-
-//~--- JDK imports ------------------------------------------------------------
+import sonia.scm.security.SessionId;
+import sonia.scm.util.HttpUtil;
 
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
-import sonia.scm.util.HttpUtil;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.*;
+
+//~--- JDK imports ------------------------------------------------------------
 
 /**
  *
  * @author Sebastian Sdorra
  */
-@RunWith(MockitoJUnitRunner.class)
-public class CookieBearerWebTokenGeneratorTest
-{
+@ExtendWith(MockitoExtension.class)
+class CookieBearerWebTokenGeneratorTest {
+
+  private final CookieBearerWebTokenGenerator tokenGenerator = new CookieBearerWebTokenGenerator();
+
+  @Mock
+  private HttpServletRequest request;
 
-  /**
-   * Method description
-   *
-   */
   @Test
-  public void testCreateToken()
-  {
-    Cookie c = mock(Cookie.class);
-
-    when(c.getName()).thenReturn(HttpUtil.COOKIE_BEARER_AUTHENTICATION);
-    when(c.getValue()).thenReturn("value");
-    when(request.getCookies()).thenReturn(new Cookie[] { c });
+  void shouldCreateToken() {
+    assignBearerCookie("value");
 
     BearerToken token = tokenGenerator.createToken(request);
 
-    assertNotNull(token);
-    assertEquals("value", token.getCredentials());
+    assertThat(token).isNotNull();
+    assertThat(token.getPrincipal()).isNull();
+    assertThat(token.getCredentials()).isEqualTo("value");
   }
 
-  /**
-   * Method description
-   *
-   */
   @Test
-  public void testCreateTokenWithWrongCookie()
-  {
+  void shouldCreateTokenWithSessionId() {
+    when(request.getHeader(HttpUtil.HEADER_SCM_SESSION)).thenReturn("abc123");
+
+    assignBearerCookie("authc");
+
+    BearerToken token = tokenGenerator.createToken(request);
+
+    assertThat(token).isNotNull();
+    assertThat(token.getPrincipal()).isEqualTo(SessionId.valueOf("abc123"));
+    assertThat(token.getCredentials()).isEqualTo("authc");
+  }
+
+  private void assignBearerCookie(String value) {
+    assignCookie(HttpUtil.COOKIE_BEARER_AUTHENTICATION, value);
+  }
+
+  private void assignCookie(String name, String value) {
     Cookie c = mock(Cookie.class);
 
-    when(c.getName()).thenReturn("other-cookie");
+    when(c.getName()).thenReturn(name);
+    lenient().when(c.getValue()).thenReturn(value);
     when(request.getCookies()).thenReturn(new Cookie[]{c});
-    assertNull(tokenGenerator.createToken(request));
   }
 
-  /**
-   * Method description
-   *
-   */
   @Test
-  public void testCreateTokenWithoutCookies()
-  {
-    assertNull(tokenGenerator.createToken(request));
+  void shouldNotCreateTokenForWrongCookie() {
+    assignCookie("other-cookie", "with-some-value");
+
+    BearerToken token = tokenGenerator.createToken(request);
+    assertThat(token).isNull();
   }
 
-  //~--- fields ---------------------------------------------------------------
-
-  /** Field description */
-  private final CookieBearerWebTokenGenerator tokenGenerator =
-    new CookieBearerWebTokenGenerator();
-
-  /** Field description */
-  @Mock
-  private HttpServletRequest request;
+  @Test
+  void shouldNotCreateTokenWithoutCookies() {
+    BearerToken token = tokenGenerator.createToken(request);
+    assertThat(token).isNull();
+  }
 }

scm-webapp/src/test/java/sonia/scm/web/security/DefaultAdministrationContextTest.java

@@ -0,0 +1,72 @@
+package sonia.scm.web.security;
+
+import com.google.inject.Guice;
+import com.google.inject.Injector;
+import org.apache.shiro.SecurityUtils;
+import org.apache.shiro.mgt.DefaultSecurityManager;
+import org.apache.shiro.mgt.SecurityManager;
+import org.apache.shiro.subject.Subject;
+import org.apache.shiro.util.ThreadContext;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+class DefaultAdministrationContextTest {
+
+  private DefaultAdministrationContext context;
+
+  @Mock
+  private Subject subject;
+
+  @BeforeEach
+  void create() {
+    Injector injector = Guice.createInjector();
+    SecurityManager securityManager = new DefaultSecurityManager();
+
+    context = new DefaultAdministrationContext(injector, securityManager);
+  }
+
+  @Test
+  void shouldBindSubject() {
+    context.runAsAdmin(() -> {
+      Subject adminSubject = SecurityUtils.getSubject();
+      assertThat(adminSubject.getPrincipal()).isEqualTo("scmsystem");
+    });
+  }
+
+  @Test
+  void shouldBindSubjectEvenIfAlreadyBound() {
+    ThreadContext.bind(subject);
+    try {
+
+      context.runAsAdmin(() -> {
+        Subject adminSubject = SecurityUtils.getSubject();
+        assertThat(adminSubject.getPrincipal()).isEqualTo("scmsystem");
+      });
+
+    } finally {
+      ThreadContext.unbindSubject();
+    }
+  }
+
+  @Test
+  void shouldRestoreCurrentSubject() {
+    when(subject.getPrincipal()).thenReturn("tricia");
+    ThreadContext.bind(subject);
+    try {
+      context.runAsAdmin(() -> {});
+      Subject currentSubject = SecurityUtils.getSubject();
+      assertThat(currentSubject.getPrincipal()).isEqualTo("tricia");
+    } finally {
+      ThreadContext.unbindSubject();
+    }
+  }
+
+}