Java: Add RESP2 support

CHANGELOG.md

@@ -16,6 +16,7 @@
 * Java: Add binary version of `ZRANK WITHSCORE` ([#2896](https://github.com/valkey-io/valkey-glide/pull/2896))
 * Go: Add `ZCARD` ([#2838](https://github.com/valkey-io/valkey-glide/pull/2838))
 * Go: Add `BZPopMin` ([#2849](https://github.com/valkey-io/valkey-glide/pull/2849))
+* Java: Add `RESP2` support ([#2383](https://github.com/valkey-io/valkey-glide/pull/2383))
 
 #### Breaking Changes
 

java/client/src/main/java/glide/api/models/configuration/BaseClientConfiguration.java

@@ -66,6 +66,12 @@ public abstract class BaseClientConfiguration {
      */
     private final ThreadPoolResource threadPoolResource;
 
+    /**
+     * Serialization protocol to be used with the server. If not set, {@link ProtocolVersion#RESP3}
+     * will be used.
+     */
+    private final ProtocolVersion protocol;
+
     public abstract BaseSubscriptionConfiguration getSubscriptionConfiguration();
 
     /**

java/client/src/main/java/glide/api/models/configuration/ProtocolVersion.java

@@ -0,0 +1,10 @@
+/** Copyright Valkey GLIDE Project Contributors - SPDX Identifier: Apache-2.0 */
+package glide.api.models.configuration;
+
+/** Represents the communication protocol with the server. */
+public enum ProtocolVersion {
+    /** Use RESP3 to communicate with the server nodes. */
+    RESP3,
+    /** Use RESP2 to communicate with the server nodes. */
+    RESP2
+}

java/client/src/main/java/glide/managers/ConnectionManager.java

@@ -13,6 +13,7 @@
 import glide.api.models.configuration.GlideClientConfiguration;
 import glide.api.models.configuration.GlideClusterClientConfiguration;
 import glide.api.models.configuration.NodeAddress;
+import glide.api.models.configuration.ProtocolVersion;
 import glide.api.models.configuration.ReadFrom;
 import glide.api.models.exceptions.ClosingException;
 import glide.api.models.exceptions.ConfigurationError;
@@ -132,6 +133,10 @@ private ConnectionRequest.Builder setupConnectionRequestBuilderBaseConfiguration
             connectionRequestBuilder.setClientAz(configuration.getClientAZ());
         }
 
+        if (configuration.getProtocol() != null) {
+            connectionRequestBuilder.setProtocolValue(configuration.getProtocol().ordinal());
+        }
+
         return connectionRequestBuilder;
     }
 
@@ -159,7 +164,10 @@ private ConnectionRequest.Builder setupConnectionRequestBuilderGlideClient(
         }
 
         if (configuration.getSubscriptionConfiguration() != null) {
-            // TODO throw ConfigurationError if RESP2
+            if (configuration.getProtocol() == ProtocolVersion.RESP2) {
+                throw new ConfigurationError(
+                        "PubSub subscriptions require RESP3 protocol, but RESP2 was configured.");
+            }
             var subscriptionsBuilder = PubSubSubscriptions.newBuilder();
             for (var entry : configuration.getSubscriptionConfiguration().getSubscriptions().entrySet()) {
                 var channelsBuilder = PubSubChannelsOrPatterns.newBuilder();
@@ -211,7 +219,10 @@ private ConnectionRequest.Builder setupConnectionRequestBuilderGlideClusterClien
         connectionRequestBuilder.setClusterModeEnabled(true);
 
         if (configuration.getSubscriptionConfiguration() != null) {
-            // TODO throw ConfigurationError if RESP2
+            if (configuration.getProtocol() == ProtocolVersion.RESP2) {
+                throw new ConfigurationError(
+                        "PubSub subscriptions require RESP3 protocol, but RESP2 was configured.");
+            }
             var subscriptionsBuilder = PubSubSubscriptions.newBuilder();
             for (var entry : configuration.getSubscriptionConfiguration().getSubscriptions().entrySet()) {
                 var channelsBuilder = PubSubChannelsOrPatterns.newBuilder();

java/client/src/test/java/glide/managers/ConnectionManagerTest.java

@@ -28,6 +28,7 @@
 import glide.api.models.configuration.GlideClientConfiguration;
 import glide.api.models.configuration.GlideClusterClientConfiguration;
 import glide.api.models.configuration.NodeAddress;
+import glide.api.models.configuration.ProtocolVersion;
 import glide.api.models.configuration.ReadFrom;
 import glide.api.models.configuration.ServerCredentials;
 import glide.api.models.configuration.StandaloneSubscriptionConfiguration;
@@ -146,6 +147,7 @@ public void connection_request_protobuf_generation_with_all_fields_set() {
                                         .build())
                         .databaseId(DATABASE_ID)
                         .clientName(CLIENT_NAME)
+                        .protocol(ProtocolVersion.RESP3)
                         .subscriptionConfiguration(
                                 StandaloneSubscriptionConfiguration.builder()
                                         .subscription(EXACT, gs("channel_1"))
@@ -180,6 +182,7 @@ public void connection_request_protobuf_generation_with_all_fields_set() {
                                         .build())
                         .setDatabaseId(DATABASE_ID)
                         .setClientName(CLIENT_NAME)
+                        .setProtocol(ConnectionRequestOuterClass.ProtocolVersion.RESP3)
                         .setPubsubSubscriptions(
                                 PubSubSubscriptions.newBuilder()
                                         .putAllChannelsOrPatternsByType(

java/integTest/src/test/java/glide/ConnectionTests.java

@@ -23,6 +23,7 @@
 import glide.api.models.configuration.AdvancedGlideClientConfiguration;
 import glide.api.models.configuration.AdvancedGlideClusterClientConfiguration;
 import glide.api.models.configuration.BackoffStrategy;
+import glide.api.models.configuration.ProtocolVersion;
 import glide.api.models.configuration.ReadFrom;
 import glide.api.models.configuration.RequestRoutingConfiguration;
 import glide.api.models.exceptions.ClosingException;
@@ -36,22 +37,28 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Timeout;
 import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.EnumSource;
 import org.junit.jupiter.params.provider.ValueSource;
 
 @Timeout(10) // seconds
 public class ConnectionTests {
 
-    @Test
+    @ParameterizedTest
+    @EnumSource(ProtocolVersion.class)
     @SneakyThrows
-    public void basic_client() {
-        var regularClient = GlideClient.createClient(commonClientConfig().build()).get();
+    public void basic_client(ProtocolVersion protocol) {
+        var regularClient =
+                GlideClient.createClient(commonClientConfig().protocol(protocol).build()).get();
         regularClient.close();
     }
 
-    @Test
+    @ParameterizedTest
+    @EnumSource(ProtocolVersion.class)
     @SneakyThrows
-    public void cluster_client() {
-        var clusterClient = GlideClusterClient.createClient(commonClusterClientConfig().build()).get();
+    public void cluster_client(ProtocolVersion protocol) {
+        var clusterClient =
+                GlideClusterClient.createClient(commonClusterClientConfig().protocol(protocol).build())
+                        .get();
         clusterClient.close();
     }
 

java/integTest/src/test/java/glide/PubSubTests.java

@@ -27,6 +27,7 @@
 import glide.api.models.configuration.BaseSubscriptionConfiguration.MessageCallback;
 import glide.api.models.configuration.ClusterSubscriptionConfiguration;
 import glide.api.models.configuration.ClusterSubscriptionConfiguration.PubSubClusterChannelMode;
+import glide.api.models.configuration.ProtocolVersion;
 import glide.api.models.configuration.RequestRoutingConfiguration.SlotKeyRoute;
 import glide.api.models.configuration.RequestRoutingConfiguration.SlotType;
 import glide.api.models.configuration.StandaloneSubscriptionConfiguration;
@@ -280,6 +281,31 @@ private void skipTestsOnMac() {
                 "PubSub doesn't work on mac OS");
     }
 
+    @SneakyThrows
+    @ParameterizedTest(name = "standalone = {0}")
+    @ValueSource(booleans = {true, false})
+    public void config_error_on_resp2(boolean standalone) {
+        if (standalone) {
+            var config =
+                    commonClientConfig()
+                            .subscriptionConfiguration(StandaloneSubscriptionConfiguration.builder().build())
+                            .protocol(ProtocolVersion.RESP2)
+                            .build();
+            var exception =
+                    assertThrows(ConfigurationError.class, () -> GlideClient.createClient(config));
+            assertTrue(exception.getMessage().contains("PubSub subscriptions require RESP3 protocol"));
+        } else {
+            var config =
+                    commonClusterClientConfig()
+                            .subscriptionConfiguration(ClusterSubscriptionConfiguration.builder().build())
+                            .protocol(ProtocolVersion.RESP2)
+                            .build();
+            var exception =
+                    assertThrows(ConfigurationError.class, () -> GlideClusterClient.createClient(config));
+            assertTrue(exception.getMessage().contains("PubSub subscriptions require RESP3 protocol"));
+        }
+    }
+
     /** Similar to `test_pubsub_exact_happy_path` in python client tests. */
     @SneakyThrows
     @ParameterizedTest(name = "standalone = {0}, read messages via {1}")