Add support for EPSILON and WITHATTRIBS arguments in VSIM command

.github/wordlist.txt

@@ -340,4 +340,6 @@ SVS
 Hitless
 hitless
 noninstantiability
-Changelog
+Changelog
+WITHATTRIBS
+vsimWithScoreWithAttribs

RELEASE-NOTES.md

@@ -63,4 +63,4 @@ If you need any support, meet Lettuce at
 
 ---
 
-**Full Changelog**: [6.8.0.RELEASE...7.0.0.BETA1](https://github.com/redis/lettuce/compare/6.8.0.RELEASE...v7.0.0.BETA1)
+**Full Changelog**: [6.8.0.RELEASE...7.0.0.BETA1](https://github.com/redis/lettuce/compare/6.8.0.RELEASE...v7.0.0.BETA1)

docs/user-guide/vector-sets.md

@@ -121,10 +121,47 @@ VSimArgs simArgs = VSimArgs.Builder
     .build();
 
 Map<String, Double> resultsWithScores = vectorSet.vsimWithScore("points", simArgs, 0.9, 0.1);
-resultsWithScores.forEach((element, score) -> 
+resultsWithScores.forEach((element, score) ->
     System.out.println(element + ": " + score));
 ```
 
+### Similarity Cutoff with EPSILON
+
+Use EPSILON to apply a maximum distance cutoff so that only sufficiently similar results are returned.
+The cutoff is defined as a distance threshold epsilon in [0.0, 1.0]; results must have similarity ≥ 1 − epsilon.
+Smaller epsilon values yield fewer, more similar results.
+
+```java
+VSimArgs simArgs = VSimArgs.Builder
+    .count(10)
+    .epsilon(0.2)            // distance cutoff; results have similarity >= 0.8
+    .build();
+
+Map<String, Double> results = vectorSet.vsimWithScore("points", simArgs, 0.9, 0.1);
+```
+
+
+### Including Attributes in Results with WITHATTRIBS
+
+Attributes are included by using the API variant that emits WITHATTRIBS. Use vsimWithScoreWithAttribs(...) to obtain scores and attributes per element.
+
+```java
+VSimArgs args = VSimArgs.Builder
+    .count(10)
+    .epsilon(0.2)
+    .build();
+
+Map<String, VSimScoreAttribs> results = vectorSet.vsimWithScoreWithAttribs("points", args, 0.9, 0.1);
+results.forEach((element, sa) -> {
+    double score = sa.getScore();
+    String attrs = sa.getAttributes();
+    System.out.println(element + ": score=" + score + ", attrs=" + attrs);
+});
+```
+
+Note: WITHATTRIBS requires a Redis version that supports returning attributes (Redis 8.2+). Methods are marked @Experimental and subject to change.
+
+
 ## Element Attributes and Filtering
 
 ### Setting and Getting Attributes
@@ -761,4 +798,4 @@ public class VectorMigrationService {
         public Map<String, Object> getMetadata() { return metadata; }
     }
 }
-```
+```

src/main/java/io/lettuce/core/AbstractRedisAsyncCommands.java

@@ -63,6 +63,7 @@
 import io.lettuce.core.search.arguments.SugGetArgs;
 import io.lettuce.core.search.arguments.SynUpdateArgs;
 import io.lettuce.core.vector.RawVector;
+import io.lettuce.core.vector.VSimScoreAttribs;
 import io.lettuce.core.vector.VectorMetadata;
 
 import java.time.Duration;
@@ -2073,6 +2074,26 @@ public RedisFuture<Map<V, Double>> vsimWithScore(K key, VSimArgs args, V element
         return dispatch(vectorSetCommandBuilder.vsimWithScore(key, args, element));
     }
 
+    @Override
+    public RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, Double... vectors) {
+        return dispatch(vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, null, vectors));
+    }
+
+    @Override
+    public RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, V element) {
+        return dispatch(vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, null, element));
+    }
+
+    @Override
+    public RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs args, Double... vectors) {
+        return dispatch(vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, args, vectors));
+    }
+
+    @Override
+    public RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs args, V element) {
+        return dispatch(vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, args, element));
+    }
+
     @Override
     public RedisFuture<List<K>> keys(K pattern) {
         return dispatch(commandBuilder.keys(pattern));

src/main/java/io/lettuce/core/AbstractRedisReactiveCommands.java

@@ -67,6 +67,7 @@
 import io.lettuce.core.tracing.TraceContextProvider;
 import io.lettuce.core.tracing.Tracing;
 import io.lettuce.core.vector.RawVector;
+import io.lettuce.core.vector.VSimScoreAttribs;
 import io.lettuce.core.vector.VectorMetadata;
 import io.netty.util.concurrent.EventExecutorGroup;
 import io.netty.util.concurrent.ImmediateEventExecutor;
@@ -2138,6 +2139,26 @@ public Mono<Map<V, Double>> vsimWithScore(K key, VSimArgs args, V element) {
         return createMono(() -> vectorSetCommandBuilder.vsimWithScore(key, args, element));
     }
 
+    @Override
+    public Mono<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, Double... vectors) {
+        return createMono(() -> vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, null, vectors));
+    }
+
+    @Override
+    public Mono<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, V element) {
+        return createMono(() -> vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, null, element));
+    }
+
+    @Override
+    public Mono<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs args, Double... vectors) {
+        return createMono(() -> vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, args, vectors));
+    }
+
+    @Override
+    public Mono<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs args, V element) {
+        return createMono(() -> vectorSetCommandBuilder.vsimWithScoreWithAttribs(key, args, element));
+    }
+
     @Override
     public Flux<K> keys(K pattern) {
         return createDissolvingFlux(() -> commandBuilder.keys(pattern));

src/main/java/io/lettuce/core/RedisVectorSetCommandBuilder.java

@@ -18,6 +18,7 @@
 import io.lettuce.core.protocol.RedisCommand;
 import io.lettuce.core.vector.RawVector;
 import io.lettuce.core.vector.VectorMetadata;
+import io.lettuce.core.vector.VSimScoreAttribs;
 
 import java.util.Arrays;
 import java.util.List;
@@ -383,7 +384,7 @@ public Command<K, V, List<V>> vsim(K key, VSimArgs vSimArgs, Double[] vectors) {
         if (vectors.length > 1) {
             args.add(CommandKeyword.VALUES);
             args.add(vectors.length);
-            Arrays.stream(vectors).map(Object::toString).forEach(args::add);
+            Arrays.stream(vectors).forEach(args::add);
         } else {
             args.add(vectors[0]);
         }
@@ -463,7 +464,7 @@ public Command<K, V, Map<V, Double>> vsimWithScore(K key, VSimArgs vSimArgs, Dou
         if (vectors.length > 1) {
             args.add(CommandKeyword.VALUES);
             args.add(vectors.length);
-            Arrays.stream(vectors).map(Object::toString).forEach(args::add);
+            Arrays.stream(vectors).forEach(args::add);
         } else {
             args.add(vectors[0]);
         }
@@ -500,4 +501,50 @@ public Command<K, V, Map<V, Double>> vsimWithScore(K key, VSimArgs vSimArgs, V e
         return createCommand(VSIM, new ValueDoubleMapOutput<>(codec), args);
     }
 
+    // WITHSCORES WITHATTRIBS variants
+    public Command<K, V, Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, Double[] vectors) {
+        return vsimWithScoreWithAttribs(key, null, vectors);
+    }
+
+    public Command<K, V, Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, V element) {
+        return vsimWithScoreWithAttribs(key, null, element);
+    }
+
+    public Command<K, V, Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs vSimArgs, Double[] vectors) {
+        notNullKey(key);
+        notEmpty(vectors);
+
+        CommandArgs<K, V> args = new CommandArgs<>(codec).addKey(key);
+
+        if (vectors.length > 1) {
+            args.add(CommandKeyword.VALUES);
+            args.add(vectors.length);
+            Arrays.stream(vectors).forEach(args::add);
+        } else {
+            args.add(vectors[0]);
+        }
+
+        args.add(WITHSCORES).add(WITHATTRIBS);
+
+        if (vSimArgs != null) {
+            vSimArgs.build(args);
+        }
+
+        return createCommand(VSIM, new VSimScoreAttribsMapOutput<>(codec), args);
+    }
+
+    public Command<K, V, Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs vSimArgs, V element) {
+        notNullKey(key);
+        notNullKey(element);
+
+        CommandArgs<K, V> args = new CommandArgs<>(codec).addKey(key).add(ELE).addValue(element).add(WITHSCORES)
+                .add(WITHATTRIBS);
+
+        if (vSimArgs != null) {
+            vSimArgs.build(args);
+        }
+
+        return createCommand(VSIM, new VSimScoreAttribsMapOutput<>(codec), args);
+    }
+
 }

src/main/java/io/lettuce/core/VSimArgs.java

@@ -11,6 +11,7 @@
 import io.lettuce.core.protocol.CommandKeyword;
 
 import java.util.Optional;
+import java.util.OptionalDouble;
 
 /**
  * Argument list builder for the Redis <a href="https://redis.io/docs/latest/commands/vsim/">VSIM</a> command. Static import the
@@ -36,6 +37,8 @@ public class VSimArgs implements CompositeArgument {
 
     private Optional<Boolean> noThread = Optional.empty();
 
+    private Optional<Double> epsilon = Optional.empty();
+
     /**
      * Builder entry points for {@link VSimArgs}.
      * <p>
@@ -266,10 +269,28 @@ public VSimArgs noThread(boolean noThread) {
         return this;
     }
 
+    /**
+     * Sets the EPSILON distance cutoff for approximate vector similarity matching; results must have similarity ≥ 1 − epsilon.
+     * In other words, this is a maximum distance threshold used to filter VSIM results.
+     *
+     * @param delta the similarity threshold delta value, must be within [0.0, 1.0] inclusive
+     * @return {@code this}
+     * @throws IllegalArgumentException if delta is outside the valid range [0.0, 1.0]
+     */
+    public VSimArgs epsilon(double delta) {
+        if (delta < 0.0 || delta > 1.0) {
+            throw new IllegalArgumentException("EPSILON must be in range [0.0, 1.0], got: " + delta);
+        }
+        this.epsilon = Optional.of(delta);
+        return this;
+    }
+
     @Override
     public <K, V> void build(CommandArgs<K, V> args) {
         count.ifPresent(Long -> args.add(CommandKeyword.COUNT).add(Long));
 
+        epsilon.ifPresent(d -> args.add(CommandKeyword.EPSILON).add(d));
+
         explorationFactor.ifPresent(Long -> args.add(CommandKeyword.EF).add(Long));
 
         filter.ifPresent(s -> args.add(CommandKeyword.FILTER).add(s));

src/main/java/io/lettuce/core/api/async/RedisVectorSetAsyncCommands.java

@@ -14,6 +14,7 @@
 import io.lettuce.core.annotations.Experimental;
 import io.lettuce.core.json.JsonValue;
 import io.lettuce.core.vector.RawVector;
+import io.lettuce.core.vector.VSimScoreAttribs;
 import io.lettuce.core.vector.VectorMetadata;
 
 /**
@@ -487,4 +488,78 @@ public interface RedisVectorSetAsyncCommands<K, V> {
     @Experimental
     RedisFuture<Map<V, Double>> vsimWithScore(K key, VSimArgs args, V element);
 
+    /**
+     * Finds the most similar vectors to the given query vector in the vector set stored at {@code key} and returns them with
+     * their similarity scores and attributes.
+     * <p>
+     * The similarity scores represent the distance between the query vector and the result vectors. Attributes are returned as
+     * a server-provided string.
+     * <p>
+     * Time complexity: O(log(N)) where N is the number of elements in the vector set
+     *
+     * @param key the key of the vector set
+     * @param vectors the query vector values as floating point numbers
+     * @return a map of elements to their (score, attributes), or an empty map if the key does not exist
+     * @since 7.0
+     * @see <a href="https://redis.io/docs/latest/commands/vsim/">Redis Documentation: VSIM</a>
+     */
+    @Experimental
+    RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, Double... vectors);
+
+    /**
+     * Finds the most similar vectors to the given element's vector in the vector set stored at {@code key} and returns them
+     * with their similarity scores and attributes.
+     * <p>
+     * The similarity scores represent the distance between the specified element's vector and the result vectors. Attributes
+     * are returned as a server-provided string.
+     * <p>
+     * Time complexity: O(log(N)) where N is the number of elements in the vector set
+     *
+     * @param key the key of the vector set
+     * @param element the name of the element whose vector will be used as the query
+     * @return a map of elements to their (score, attributes), or an empty map if the key or element does not exist
+     * @since 7.0
+     * @see <a href="https://redis.io/docs/latest/commands/vsim/">Redis Documentation: VSIM</a>
+     */
+    @Experimental
+    RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, V element);
+
+    /**
+     * Finds the most similar vectors to the given query vector in the vector set stored at {@code key} with additional options
+     * and returns them with their similarity scores and attributes.
+     * <p>
+     * The {@link VSimArgs} allows configuring various options such as the number of results ({@code COUNT}), epsilon cutoff
+     * ({@code EPSILON}), exploration factor ({@code EF}), and filtering.
+     * <p>
+     * Time complexity: O(log(N)) where N is the number of elements in the vector set
+     *
+     * @param key the key of the vector set
+     * @param args the additional arguments for the VSIM command
+     * @param vectors the query vector values as floating point numbers
+     * @return a map of elements to their (score, attributes), or an empty map if the key does not exist
+     * @since 7.0
+     * @see <a href="https://redis.io/docs/latest/commands/vsim/">Redis Documentation: VSIM</a>
+     */
+    @Experimental
+    RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs args, Double... vectors);
+
+    /**
+     * Finds the most similar vectors to the given element's vector in the vector set stored at {@code key} with additional
+     * options and returns them with their similarity scores and attributes.
+     * <p>
+     * This method combines using an existing element's vector as the query with the ability to specify additional options via
+     * {@link VSimArgs}. Attributes are returned as a server-provided string.
+     * <p>
+     * Time complexity: O(log(N)) where N is the number of elements in the vector set
+     *
+     * @param key the key of the vector set
+     * @param element the name of the element whose vector will be used as the query
+     * @param args the additional arguments for the VSIM command
+     * @return a map of elements to their (score, attributes), or an empty map if the key or element does not exist
+     * @since 7.0
+     * @see <a href="https://redis.io/docs/latest/commands/vsim/">Redis Documentation: VSIM</a>
+     */
+    @Experimental
+    RedisFuture<Map<V, VSimScoreAttribs>> vsimWithScoreWithAttribs(K key, VSimArgs args, V element);
+
 }