Remove support for MongoDB 4.0

* Remove branching code in the driver based on 4.0 version checks
* Remove testing of 4.0
* Clean up tests

JAVA-5831

Author: jyemin

.evergreen/.evg.yml

@@ -599,16 +599,6 @@ functions:
           LOGIN_CONTEXT_NAME=${LOGIN_CONTEXT_NAME} \
           .evergreen/run-gssapi-auth-test.sh
 
-  "run mmapv1 storage test":
-    - command: shell.exec
-      type: test
-      params:
-        silent: true
-        working_dir: "src"
-        script: |
-          ${PREPARE_SHELL}
-          PROJECT_DIRECTORY=${PROJECT_DIRECTORY} JAVA_VERSION=${JAVA_VERSION} TOPOLOGY=${TOPOLOGY} STORAGE_ENGINE=${STORAGE_ENGINE} MONGODB_URI="${MONGODB_URI}" .evergreen/run-mmapv1-storage-test.sh
-
   run socks5 tests:
     - command: shell.exec
       type: test
@@ -1577,11 +1567,6 @@ tasks:
               TEST_LAMBDA_DIRECTORY: ${PROJECT_DIRECTORY}/driver-lambda/
               AWS_REGION: us-east-1
 
-    - name: "mmapv1-storage-test"
-      commands:
-        - func: "bootstrap mongo-orchestration"
-        - func: "run mmapv1 storage test"
-
     - name: "test-kms-tls-invalid-cert"
       tags: ["kms-tls"]
       commands:
@@ -1762,10 +1747,6 @@ axes:
            # Multiple mongos instances can be specified in the connection string
            # for this version.
            SAFE_FOR_MULTI_MONGOS: true
-      - id: "4.0"
-        display_name: "4.0"
-        variables:
-           VERSION: "4.0"
   - id: os
     display_name: OS
     values:
@@ -1886,15 +1867,6 @@ axes:
         variables:
           SCALA: "2.13"
 
-  # Choice of MongoDB storage engine
-  - id: storage-engine
-    display_name: Storage
-    values:
-      - id: mmapv1
-        display_name: MMAPv1
-        variables:
-           STORAGE_ENGINE: "mmapv1"
-
   - id: api-version
     display_name: API Version
     values:
@@ -2201,7 +2173,7 @@ buildvariants:
     - name: "test-bson-and-crypt"
 
 - matrix_name: "tests-jdk8-unsecure"
-  matrix_spec: { auth: "noauth", ssl: "nossl", jdk: "jdk8", version: ["4.0", "4.2", "4.4", "5.0", "6.0", "7.0", "8.0", "latest"],
+  matrix_spec: { auth: "noauth", ssl: "nossl", jdk: "jdk8", version: ["4.2", "4.4", "5.0", "6.0", "7.0", "8.0", "latest"],
                  topology: "*", os: "linux" }
   display_name: "${version} ${topology} ${auth} ${ssl} ${jdk} ${os} "
   tags: ["tests-variant"]
@@ -2213,7 +2185,7 @@ buildvariants:
 
 - matrix_name: "tests-jdk-secure"
   matrix_spec: { auth: "auth", ssl: "ssl", jdk: [ "jdk8", "jdk17", "jdk21"],
-                 version: ["4.0", "4.2", "4.4", "5.0", "6.0", "7.0", "8.0", "latest" ],
+                 version: ["4.2", "4.4", "5.0", "6.0", "7.0", "8.0", "latest" ],
                  topology: "*", os: "linux" }
   display_name: "${version} ${topology} ${auth} ${ssl} ${jdk} ${os} "
   tags: ["tests-variant"]
@@ -2427,12 +2399,6 @@ buildvariants:
   tasks:
     - name: "publish-release"
 
-- matrix_name: "tests-storage-engines"
-  matrix_spec: { auth: "noauth", ssl: "nossl", jdk: "jdk8", os: "linux", version: ["4.0"], topology: ["replicaset", "sharded-cluster"], storage-engine: "mmapv1" }
-  display_name: "${version} Storage ${storage-engine} ${jdk} ${os} ${topology}"
-  tasks:
-    - name: "mmapv1-storage-test"
-
 - matrix_name: "kms-tls-test"
   matrix_spec: { os: "linux", version: [ "5.0" ], topology: ["standalone"] }
   display_name: "CSFLE KMS TLS"

.evergreen/run-mmapv1-storage-test.sh

@@ -55,12 +55,12 @@ public class ServerDescription {
      * The minimum supported driver server version
      * @since 3.8
      */
-    public static final String MIN_DRIVER_SERVER_VERSION = "3.6";
+    public static final String MIN_DRIVER_SERVER_VERSION = "4.2";
     /**
      * The minimum supported driver wire version
      * @since 3.8
      */
-    public static final int MIN_DRIVER_WIRE_VERSION = 7;
+    public static final int MIN_DRIVER_WIRE_VERSION = 8;
     /**
      * The maximum supported driver wire version
      * @since 3.8

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

@@ -60,8 +60,7 @@
 import static com.mongodb.internal.connection.ByteBufBsonDocument.createList;
 import static com.mongodb.internal.connection.ByteBufBsonDocument.createOne;
 import static com.mongodb.internal.connection.ReadConcernHelper.getReadConcernDocument;
-import static com.mongodb.internal.operation.ServerVersionHelper.FOUR_DOT_TWO_WIRE_VERSION;
-import static com.mongodb.internal.operation.ServerVersionHelper.FOUR_DOT_ZERO_WIRE_VERSION;
+import static com.mongodb.internal.operation.ServerVersionHelper.EARLIEST_WIRE_VERSION;
 
 /**
  * A command message that uses OP_MSG or OP_QUERY to send the command.
@@ -346,7 +345,6 @@ private List<BsonElement> getExtraElements(final OperationContext operationConte
 
         assertFalse(sessionContext.hasActiveTransaction() && sessionContext.isSnapshot());
         if (sessionContext.hasActiveTransaction()) {
-            checkServerVersionForTransactionSupport();
             extraElements.add(new BsonElement("txnNumber", new BsonInt64(sessionContext.getTransactionNumber())));
             if (firstMessageInTransaction) {
                 extraElements.add(new BsonElement("startTransaction", BsonBoolean.TRUE));
@@ -381,12 +379,6 @@ private void addServerApiElements(final List<BsonElement> extraElements) {
         }
     }
 
-    private void checkServerVersionForTransactionSupport() {
-        if (getSettings().getMaxWireVersion() < FOUR_DOT_TWO_WIRE_VERSION && getSettings().getServerType() == SHARD_ROUTER) {
-            throw new MongoClientException("Transactions are not supported by the MongoDB cluster to which this client is connected.");
-        }
-    }
-
 
     private void addReadConcernDocument(final List<BsonElement> extraElements, final SessionContext sessionContext) {
         BsonDocument readConcernDocument = getReadConcernDocument(sessionContext, getSettings().getMaxWireVersion());
@@ -416,7 +408,7 @@ private static OpCode getOpCode(final MessageSettings settings, final ClusterCon
     }
 
     private static boolean isServerVersionKnown(final MessageSettings settings) {
-        return settings.getMaxWireVersion() >= FOUR_DOT_ZERO_WIRE_VERSION;
+        return settings.getMaxWireVersion() >= EARLIEST_WIRE_VERSION;
     }
 
     @FunctionalInterface

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

@@ -119,7 +119,7 @@ private void handleException(final SdamIssue sdamIssue, final boolean beforeHand
         }
         if (sdamIssue.relatedToStateChange()) {
             updateDescription(sdamIssue.serverDescription());
-            if (sdamIssue.serverIsLessThanVersionFourDotTwo() || sdamIssue.relatedToShutdown()) {
+            if (sdamIssue.relatedToShutdown()) {
                 connectionPool.invalidate(sdamIssue.exception().orElse(null));
             }
             serverMonitor.connect();
@@ -130,9 +130,6 @@ private void handleException(final SdamIssue sdamIssue, final boolean beforeHand
             serverMonitor.cancelCurrentCheck();
         } else if (sdamIssue.relatedToWriteConcern() || !sdamIssue.specific()) {
             updateDescription(sdamIssue.serverDescription());
-            if (sdamIssue.serverIsLessThanVersionFourDotTwo()) {
-                connectionPool.invalidate(sdamIssue.exception().orElse(null));
-            }
             serverMonitor.connect();
         }
     }

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

@@ -35,7 +35,6 @@
 import static com.mongodb.assertions.Assertions.assertTrue;
 import static com.mongodb.internal.connection.ClusterableServer.SHUTDOWN_CODES;
 import static com.mongodb.internal.connection.ServerDescriptionHelper.unknownConnectingServerDescription;
-import static com.mongodb.internal.operation.ServerVersionHelper.FOUR_DOT_TWO_WIRE_VERSION;
 
 /**
  * See the
@@ -117,10 +116,6 @@ ServerDescription serverDescription() {
             return unknownConnectingServerDescription(context.serverId(), exception);
         }
 
-        boolean serverIsLessThanVersionFourDotTwo() {
-            return context.serverIsLessThanVersionFourDotTwo();
-        }
-
         boolean stale(final ConnectionPool connectionPool, final ServerDescription currentServerDescription) {
             return context.stale(connectionPool) || stale(exception, currentServerDescription);
         }
@@ -192,10 +187,6 @@ static final class Context {
                 this.serverMaxWireVersion = serverMaxWireVersion;
             }
 
-            private boolean serverIsLessThanVersionFourDotTwo() {
-                return serverMaxWireVersion < FOUR_DOT_TWO_WIRE_VERSION;
-            }
-
             private boolean stale(final ConnectionPool connectionPool) {
                 return connectionPoolGeneration < connectionPool.getGeneration();
             }

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

@@ -46,7 +46,6 @@
 
 import static com.mongodb.assertions.Assertions.assertNotNull;
 import static com.mongodb.internal.operation.ServerVersionHelper.serverIsLessThanVersionFourDotFour;
-import static com.mongodb.internal.operation.ServerVersionHelper.serverIsLessThanVersionFourDotTwo;
 import static java.lang.String.format;
 
 /**
@@ -70,10 +69,6 @@ private static void validateArrayFilters(final WriteConcern writeConcern) {
     private static void validateWriteRequestHint(final ConnectionDescription connectionDescription, final WriteConcern writeConcern,
                                                  final WriteRequest request) {
         if (!writeConcern.isAcknowledged()) {
-            if (request instanceof UpdateRequest && serverIsLessThanVersionFourDotTwo(connectionDescription)) {
-                throw new IllegalArgumentException(format("Hint not supported by wire version: %s",
-                        connectionDescription.getMaxWireVersion()));
-            }
             if (request instanceof DeleteRequest && serverIsLessThanVersionFourDotFour(connectionDescription)) {
                 throw new IllegalArgumentException(format("Hint not supported by wire version: %s",
                         connectionDescription.getMaxWireVersion()));
@@ -82,10 +77,6 @@ private static void validateWriteRequestHint(final ConnectionDescription connect
     }
 
     static void validateHintForFindAndModify(final ConnectionDescription connectionDescription, final WriteConcern writeConcern) {
-        if (serverIsLessThanVersionFourDotTwo(connectionDescription)) {
-            throw new IllegalArgumentException(format("Hint not supported by wire version: %s",
-                    connectionDescription.getMaxWireVersion()));
-        }
         if (!writeConcern.isAcknowledged() && serverIsLessThanVersionFourDotFour(connectionDescription)) {
             throw new IllegalArgumentException(format("Hint not supported by wire version: %s",
                     connectionDescription.getMaxWireVersion()));

driver-core/src/main/com/mongodb/internal/operation/OperationHelper.java

@@ -25,22 +25,19 @@
 public final class ServerVersionHelper {
 
     public static final int MIN_WIRE_VERSION = 0;
-    public static final int FOUR_DOT_ZERO_WIRE_VERSION = 7;
     public static final int FOUR_DOT_TWO_WIRE_VERSION = 8;
     public static final int FOUR_DOT_FOUR_WIRE_VERSION = 9;
     public static final int FIVE_DOT_ZERO_WIRE_VERSION = 12;
     public static final int SIX_DOT_ZERO_WIRE_VERSION = 17;
     public static final int SEVEN_DOT_ZERO_WIRE_VERSION = 21;
-    public static final int LATEST_WIRE_VERSION = SEVEN_DOT_ZERO_WIRE_VERSION;
+    public static final int EIGHT_DOT_ZERO_WIRE_VERSION = 21;
+    public static final int EARLIEST_WIRE_VERSION = FOUR_DOT_TWO_WIRE_VERSION;
+    public static final int LATEST_WIRE_VERSION = EIGHT_DOT_ZERO_WIRE_VERSION;
 
     public static boolean serverIsAtLeastVersionFourDotFour(final ConnectionDescription description) {
         return description.getMaxWireVersion() >= FOUR_DOT_FOUR_WIRE_VERSION;
     }
 
-    public static boolean serverIsLessThanVersionFourDotTwo(final ConnectionDescription description) {
-        return description.getMaxWireVersion() < FOUR_DOT_TWO_WIRE_VERSION;
-    }
-
     public static boolean serverIsLessThanVersionFourDotFour(final ConnectionDescription description) {
         return description.getMaxWireVersion() < FOUR_DOT_FOUR_WIRE_VERSION;
     }

driver-core/src/main/com/mongodb/internal/operation/ServerVersionHelper.java

@@ -16,7 +16,7 @@
 
 package com.mongodb.internal.connection
 
-import com.mongodb.MongoClientException
+
 import com.mongodb.MongoNamespace
 import com.mongodb.ReadConcern
 import com.mongodb.ReadPreference
@@ -43,7 +43,6 @@ import spock.lang.Specification
 import java.nio.ByteBuffer
 
 import static com.mongodb.internal.connection.SplittablePayload.Type.INSERT
-import static com.mongodb.internal.operation.ServerVersionHelper.FOUR_DOT_ZERO_WIRE_VERSION
 import static com.mongodb.internal.operation.ServerVersionHelper.LATEST_WIRE_VERSION
 
 /**
@@ -360,30 +359,6 @@ class CommandMessageSpecification extends Specification {
         output.close()
     }
 
-    def 'should throw if wire version and sharded cluster does not support transactions'() {
-        given:
-        def messageSettings = MessageSettings.builder().serverType(ServerType.SHARD_ROUTER)
-                .maxWireVersion(FOUR_DOT_ZERO_WIRE_VERSION).build()
-        def payload = new SplittablePayload(INSERT, [new BsonDocument('a', new BsonInt32(1))], true, fieldNameValidator)
-        def message = new CommandMessage(namespace, command, fieldNameValidator, ReadPreference.primary(), messageSettings,
-                false, payload, ClusterConnectionMode.MULTIPLE, null)
-        def output = new ByteBufferBsonOutput(new SimpleBufferProvider())
-        def sessionContext = Stub(SessionContext) {
-            getReadConcern() >> ReadConcern.DEFAULT
-            hasActiveTransaction() >> true
-        }
-
-        when:
-        message.encode(output, new OperationContext(IgnorableRequestContext.INSTANCE, sessionContext,
-                Stub(TimeoutContext), null))
-
-        then:
-        thrown(MongoClientException)
-
-        cleanup:
-        output.close()
-    }
-
     private static BsonDocument getCommandDocument(ByteBufNIO byteBuf, ReplyHeader replyHeader) {
         new ReplyMessage<BsonDocument>(new ResponseBuffers(replyHeader, byteBuf), new BsonDocumentCodec(), 0).document
     }

driver-core/src/test/unit/com/mongodb/internal/connection/CommandMessageSpecification.groovy

@@ -48,7 +48,6 @@
 import static com.mongodb.MongoClientSettings.getDefaultCodecRegistry;
 import static com.mongodb.client.model.bulk.ClientBulkWriteOptions.clientBulkWriteOptions;
 import static com.mongodb.internal.mockito.MongoMockito.mock;
-import static com.mongodb.internal.operation.ServerVersionHelper.FOUR_DOT_ZERO_WIRE_VERSION;
 import static com.mongodb.internal.operation.ServerVersionHelper.LATEST_WIRE_VERSION;
 import static java.util.Arrays.asList;
 import static java.util.Collections.singletonList;
@@ -69,7 +68,7 @@ void encodeShouldThrowTimeoutExceptionWhenTimeoutContextIsCalled() {
         //given
         CommandMessage commandMessage = new CommandMessage(NAMESPACE, COMMAND, NoOpFieldNameValidator.INSTANCE, ReadPreference.primary(),
                 MessageSettings.builder()
-                        .maxWireVersion(FOUR_DOT_ZERO_WIRE_VERSION)
+                        .maxWireVersion(LATEST_WIRE_VERSION)
                         .serverType(ServerType.REPLICA_SET_SECONDARY)
                         .sessionSupported(true)
                         .build(),
@@ -96,7 +95,7 @@ void encodeShouldNotAddExtraElementsFromTimeoutContextWhenConnectedToMongoCrypt(
         //given
         CommandMessage commandMessage = new CommandMessage(NAMESPACE, COMMAND, NoOpFieldNameValidator.INSTANCE, ReadPreference.primary(),
                 MessageSettings.builder()
-                        .maxWireVersion(FOUR_DOT_ZERO_WIRE_VERSION)
+                        .maxWireVersion(LATEST_WIRE_VERSION)
                         .serverType(ServerType.REPLICA_SET_SECONDARY)
                         .sessionSupported(true)
                         .cryptd(true)

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

@@ -23,6 +23,7 @@
 import org.bson.BsonDocument;
 import org.bson.BsonNull;
 import org.bson.BsonValue;
+import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
@@ -39,16 +40,25 @@
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeFalse;
 
 // See https://github.com/mongodb/specifications/tree/master/source/server-discovery-and-monitoring/tests
 @RunWith(Parameterized.class)
 public class ServerDiscoveryAndMonitoringTest extends AbstractServerDiscoveryAndMonitoringTest {
 
+    private final String description;
+
     public ServerDiscoveryAndMonitoringTest(final String description, final BsonDocument definition) {
         super(definition);
+        this.description = description;
         init(serverAddress -> NO_OP_SERVER_LISTENER, NO_OP_CLUSTER_LISTENER);
     }
 
+    @Before
+    public void setUp() {
+        assumeFalse(description.startsWith("pre-42"));
+    }
+
     @Test
     public void shouldPassAllOutcomes() {
         for (BsonValue phase : getDefinition().getArray("phases")) {