JAVA-2788: Add isImplicitSession property to SessionContext

Author: jyemin

driver-async/src/main/com/mongodb/async/client/ClientSessionBinding.java

@@ -152,6 +152,11 @@ private final class AsyncClientSessionContext extends ClientSessionContext imple
         }
 
 
+        @Override
+        public boolean isImplicitSession() {
+            return ownsSession;
+        }
+
         @Override
         public boolean notifyMessageSent() {
             return clientSession.notifyMessageSent();

driver-async/src/test/unit/com/mongodb/async/client/ClientSessionBindingSpecification.groovy

@@ -149,6 +149,21 @@ class ClientSessionBindingSpecification extends Specification {
         0 * session.close()
     }
 
+    def 'owned session is implicit'() {
+        given:
+        def session = Mock(ClientSession)
+        def wrappedBinding = createStubBinding()
+
+        when:
+        def binding = new ClientSessionBinding(session, ownsSession, wrappedBinding)
+
+        then:
+        binding.getSessionContext().isImplicitSession() == ownsSession
+
+        where:
+        ownsSession << [true, false]
+    }
+    
     private AsyncReadWriteBinding createStubBinding() {
         def cluster = Mock(Cluster) {
             selectServerAsync(_, _) >> {

driver-core/src/main/com/mongodb/connection/ClusterClockAdvancingSessionContext.java

@@ -36,6 +36,11 @@ public boolean hasSession() {
         return wrapped.hasSession();
     }
 
+    @Override
+    public boolean isImplicitSession() {
+        return wrapped.isImplicitSession();
+    }
+
     @Override
     public BsonDocument getSessionId() {
         return wrapped.getSessionId();

driver-core/src/main/com/mongodb/internal/connection/NoOpSessionContext.java

@@ -38,6 +38,11 @@ public boolean hasSession() {
         return false;
     }
 
+    @Override
+    public boolean isImplicitSession() {
+        throw new UnsupportedOperationException();
+    }
+
     @Override
     public BsonDocument getSessionId() {
         throw new UnsupportedOperationException();

driver-core/src/main/com/mongodb/session/SessionContext.java

@@ -34,6 +34,14 @@ public interface SessionContext {
      */
     boolean hasSession();
 
+    /**
+     * Returns true if the session is implicit, and false if the application started the session explicity.
+     *
+     * @return true if the session is implicit
+     * @since 3.8
+     */
+    boolean isImplicitSession();
+
     /**
      * Gets the session identifier if this context has a session backing it.
      *

driver-core/src/test/functional/com/mongodb/binding/SimpleSessionContext.java

@@ -39,6 +39,11 @@ class SimpleSessionContext implements SessionContext {
 
     @Override
     public boolean hasSession() {
+        return false;
+    }
+
+    @Override
+    public boolean isImplicitSession() {
         return true;
     }
 

driver-core/src/test/unit/com/mongodb/connection/TestSessionContext.java

@@ -39,6 +39,11 @@ public boolean hasSession() {
         return false;
     }
 
+    @Override
+    public boolean isImplicitSession() {
+        throw new UnsupportedOperationException();
+    }
+
     @Override
     public BsonDocument getSessionId() {
         throw new UnsupportedOperationException();

driver-core/src/test/unit/com/mongodb/internal/session/ClientSessionContextSpecification.groovy

@@ -38,6 +38,11 @@ class ClientSessionContextSpecification extends Specification {
             false;
         }
 
+        @Override
+        boolean isImplicitSession() {
+            throw new UnsupportedOperationException()
+        }
+
         @Override
         boolean notifyMessageSent() {
             throw new UnsupportedOperationException()

driver-legacy/src/test/functional/com/mongodb/MongoClientSessionSpecification.groovy

@@ -384,7 +384,7 @@ class MongoClientSessionSpecification extends FunctionalSpecification {
     }
 
     @IgnoreIf({ !serverVersionAtLeast(3, 6) })
-    def 'should not use a session for an unacknowledged write'() {
+    def 'should not use an implicit session for an unacknowledged write'() {
         given:
         def commandListener = new TestCommandListener()
         def optionsBuilder = MongoClientOptions.builder()

driver-sync/src/main/com/mongodb/client/internal/ClientSessionBinding.java

@@ -139,6 +139,10 @@ private final class SyncClientSessionContext extends ClientSessionContext implem
             this.clientSession = clientSession;
         }
 
+        @Override
+        public boolean isImplicitSession() {
+            return ownsSession;
+        }
 
         @Override
         public boolean notifyMessageSent() {