HMGET proxy not working as expected

[moores-expedia]

Using latest 5.0.0.RELEASE:
I am providing a command interface and a class that fails with "ERR wrong number of arguments for 'hmget' command" on an empty redis instance for the HMGET command when the method signature is as specified below. Fixed hmget field parameters work fine, but when i use vargs or an Iterable, looks like the fields are not passed in to redis.

Exception/trace here:

Caused by: io.lettuce.core.RedisCommandExecutionException: ERR wrong number of arguments for 'hmget' command
	at io.lettuce.core.protocol.AsyncCommand.completeResult(AsyncCommand.java:116)
	at io.lettuce.core.protocol.AsyncCommand.complete(AsyncCommand.java:107)
	at io.lettuce.core.protocol.CommandHandler.decode(CommandHandler.java:513)
	at io.lettuce.core.protocol.CommandHandler.channelRead(CommandHandler.java:485)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
	at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86)

INTERFACE:

package lettuce;

import io.lettuce.core.RedisFuture;
import io.lettuce.core.dynamic.Commands;
import io.lettuce.core.dynamic.batch.BatchExecutor;
import io.lettuce.core.dynamic.batch.CommandBatching;

import java.util.List;
import java.util.Map;
import java.util.Set;

public interface JavaPropertyCommands extends Commands, BatchExecutor {
    RedisFuture<List<byte[]>> hmget(CommandBatching batching, byte[] key, List<byte[]> fields);
} 

CALL THROUGH INTERFACE:

package lettuce;
import io.lettuce.core.RedisClient;
import io.lettuce.core.RedisFuture;
import io.lettuce.core.RedisURI;
import io.lettuce.core.api.StatefulRedisConnection;
import io.lettuce.core.codec.ByteArrayCodec;
import io.lettuce.core.dynamic.RedisCommandFactory;
import io.lettuce.core.dynamic.batch.CommandBatching;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;

public class HmgetTest {

    public void callHmget() throws Exception {

        RedisClient client = RedisClient.create();
        RedisURI uri = RedisURI.create("redis://localhost:6379");
        StatefulRedisConnection<byte[], byte[]> connection =  client.connect(new ByteArrayCodec(), uri);
        RedisCommandFactory factory = new RedisCommandFactory(connection);
        JavaPropertyCommands commands = factory.getCommands(JavaPropertyCommands.class);

        byte[] key = "key".getBytes();
        List<byte[]> fields = new ArrayList<>();
        fields.add("f1".getBytes());
        fields.add("f2".getBytes());

        RedisFuture<List<byte[]>> f = commands.hmget(CommandBatching.flush(), key, fields);

        List<byte[]> answer = f.get(2, TimeUnit.SECONDS);
        System.out.println(answer);
    }
}

[mp911de]

Thanks a lot for the example. I can reproduce the issue which is related to byte[]. byte[] elements of an Iterable were not bound.

You can view the sent commands from the client perspective by enabling TRACE logging for io.lettuce.core.protocol. This will create a lot of logging and slows the system down – not suitable for production but handy for development.

[mp911de]

That's fixed now and available via 5.0.1.BUILD-SNAPSHOT.

[moores-expedia]

👍