From 7164805960f21c941f3d0156a18371777ad0e1f1 Mon Sep 17 00:00:00 2001
From: SanHalacogluImproving
 <144171266+SanHalacogluImproving@users.noreply.github.com>
Date: Mon, 1 Apr 2024 13:52:12 -0700
Subject: [PATCH] Java: Add hlen command. (Hash Command Group) (#159)

---
 .../src/main/java/glide/api/BaseClient.java   |  6 +++++
 .../glide/api/commands/HashBaseCommands.java  | 18 ++++++++++++++
 .../glide/api/models/BaseTransaction.java     | 17 +++++++++++++
 .../test/java/glide/api/RedisClientTest.java  | 24 +++++++++++++++++++
 .../glide/api/models/TransactionTests.java    |  4 ++++
 .../test/java/glide/SharedCommandTests.java   | 23 ++++++++++++++++++
 .../java/glide/TransactionTestUtilities.java  |  2 ++
 7 files changed, 94 insertions(+)

diff --git a/java/client/src/main/java/glide/api/BaseClient.java b/java/client/src/main/java/glide/api/BaseClient.java
index 48bf3a50b4..0a960c9c13 100644
--- a/java/client/src/main/java/glide/api/BaseClient.java
+++ b/java/client/src/main/java/glide/api/BaseClient.java
@@ -13,6 +13,7 @@
 import static redis_request.RedisRequestOuterClass.RequestType.Expire;
 import static redis_request.RedisRequestOuterClass.RequestType.ExpireAt;
 import static redis_request.RedisRequestOuterClass.RequestType.GetString;
+import static redis_request.RedisRequestOuterClass.RequestType.HLen;
 import static redis_request.RedisRequestOuterClass.RequestType.HashDel;
 import static redis_request.RedisRequestOuterClass.RequestType.HashExists;
 import static redis_request.RedisRequestOuterClass.RequestType.HashGet;
@@ -323,6 +324,11 @@ public CompletableFuture<Long> hdel(@NonNull String key, @NonNull String[] field
         return commandManager.submitNewCommand(HashDel, args, this::handleLongResponse);
     }
 
+    @Override
+    public CompletableFuture<Long> hlen(@NonNull String key) {
+        return commandManager.submitNewCommand(HLen, new String[] {key}, this::handleLongResponse);
+    }
+
     @Override
     public CompletableFuture<String[]> hmget(@NonNull String key, @NonNull String[] fields) {
         String[] arguments = ArrayUtils.addFirst(fields, key);
diff --git a/java/client/src/main/java/glide/api/commands/HashBaseCommands.java b/java/client/src/main/java/glide/api/commands/HashBaseCommands.java
index 8007106a16..3d1d8333eb 100644
--- a/java/client/src/main/java/glide/api/commands/HashBaseCommands.java
+++ b/java/client/src/main/java/glide/api/commands/HashBaseCommands.java
@@ -65,6 +65,24 @@ public interface HashBaseCommands {
      */
     CompletableFuture<Long> hdel(String key, String[] fields);
 
+    /**
+     * Returns the number of fields contained in the hash stored at <code>key</code>.
+     *
+     * @see <a href="https://redis.io/commands/hlen/">redis.io</a> for details.
+     * @param key The key of the hash.
+     * @return The number of fields in the hash, or <code>0</code> when the key does not exist.<br>
+     *     If <code>key</code> holds a value that is not a hash, an error is returned.
+     * @example
+     *     <pre>{@code
+     * Long num1 = client.hlen("myHash").get();
+     * assert num1 == 3L;
+     *
+     * Long num2 = client.hlen("nonExistingKey").get();
+     * assert num2 == 0L;
+     * }</pre>
+     */
+    CompletableFuture<Long> hlen(String key);
+
     /**
      * Returns the values associated with the specified fields in the hash stored at <code>key</code>.
      *
diff --git a/java/client/src/main/java/glide/api/models/BaseTransaction.java b/java/client/src/main/java/glide/api/models/BaseTransaction.java
index d0c1d4814c..cc9bb807da 100644
--- a/java/client/src/main/java/glide/api/models/BaseTransaction.java
+++ b/java/client/src/main/java/glide/api/models/BaseTransaction.java
@@ -18,6 +18,7 @@
 import static redis_request.RedisRequestOuterClass.RequestType.Expire;
 import static redis_request.RedisRequestOuterClass.RequestType.ExpireAt;
 import static redis_request.RedisRequestOuterClass.RequestType.GetString;
+import static redis_request.RedisRequestOuterClass.RequestType.HLen;
 import static redis_request.RedisRequestOuterClass.RequestType.HashDel;
 import static redis_request.RedisRequestOuterClass.RequestType.HashExists;
 import static redis_request.RedisRequestOuterClass.RequestType.HashGet;
@@ -394,6 +395,22 @@ public T hdel(@NonNull String key, @NonNull String[] fields) {
         return getThis();
     }
 
+    /**
+     * Returns the number of fields contained in the hash stored at <code>key</code>.
+     *
+     * @see <a href="https://redis.io/commands/hlen/">redis.io</a> for details.
+     * @param key The key of the hash.
+     * @return Command Response - The number of fields in the hash, or <code>0</code> when the key
+     *     does not exist.<br>
+     *     If <code>key</code> holds a value that is not a hash, an error is returned.
+     */
+    public T hlen(@NonNull String key) {
+        ArgsArray commandArgs = buildArgs(key);
+
+        protobufTransaction.addCommands(buildCommand(HLen, commandArgs));
+        return getThis();
+    }
+
     /**
      * Returns the values associated with the specified fields in the hash stored at <code>key</code>.
      *
diff --git a/java/client/src/test/java/glide/api/RedisClientTest.java b/java/client/src/test/java/glide/api/RedisClientTest.java
index 2aee44867d..a371d48a66 100644
--- a/java/client/src/test/java/glide/api/RedisClientTest.java
+++ b/java/client/src/test/java/glide/api/RedisClientTest.java
@@ -29,6 +29,7 @@
 import static redis_request.RedisRequestOuterClass.RequestType.Expire;
 import static redis_request.RedisRequestOuterClass.RequestType.ExpireAt;
 import static redis_request.RedisRequestOuterClass.RequestType.GetString;
+import static redis_request.RedisRequestOuterClass.RequestType.HLen;
 import static redis_request.RedisRequestOuterClass.RequestType.HashDel;
 import static redis_request.RedisRequestOuterClass.RequestType.HashExists;
 import static redis_request.RedisRequestOuterClass.RequestType.HashGet;
@@ -855,6 +856,29 @@ public void hdel_success() {
         assertEquals(value, payload);
     }
 
+    @SneakyThrows
+    @Test
+    public void hlen_success() {
+        // setup
+        String key = "testKey";
+        String[] args = {key};
+        Long value = 2L;
+
+        CompletableFuture<Long> testResponse = new CompletableFuture<>();
+        testResponse.complete(value);
+
+        // match on protobuf request
+        when(commandManager.<Long>submitNewCommand(eq(HLen), eq(args), any())).thenReturn(testResponse);
+
+        // exercise
+        CompletableFuture<Long> response = service.hlen(key);
+        Long payload = response.get();
+
+        // verify
+        assertEquals(testResponse, response);
+        assertEquals(value, payload);
+    }
+
     @SneakyThrows
     @Test
     public void hmget_success() {
diff --git a/java/client/src/test/java/glide/api/models/TransactionTests.java b/java/client/src/test/java/glide/api/models/TransactionTests.java
index 7d1f98430f..dd8d2af71c 100644
--- a/java/client/src/test/java/glide/api/models/TransactionTests.java
+++ b/java/client/src/test/java/glide/api/models/TransactionTests.java
@@ -16,6 +16,7 @@
 import static redis_request.RedisRequestOuterClass.RequestType.Expire;
 import static redis_request.RedisRequestOuterClass.RequestType.ExpireAt;
 import static redis_request.RedisRequestOuterClass.RequestType.GetString;
+import static redis_request.RedisRequestOuterClass.RequestType.HLen;
 import static redis_request.RedisRequestOuterClass.RequestType.HashDel;
 import static redis_request.RedisRequestOuterClass.RequestType.HashExists;
 import static redis_request.RedisRequestOuterClass.RequestType.HashGet;
@@ -146,6 +147,9 @@ public void transaction_builds_protobuf_request(BaseTransaction<?> transaction)
         transaction.hdel("key", new String[] {"field"});
         results.add(Pair.of(HashDel, ArgsArray.newBuilder().addArgs("key").addArgs("field").build()));
 
+        transaction.hlen("key");
+        results.add(Pair.of(HLen, ArgsArray.newBuilder().addArgs("key").build()));
+
         transaction.hmget("key", new String[] {"field"});
         results.add(Pair.of(HashMGet, ArgsArray.newBuilder().addArgs("key").addArgs("field").build()));
 
diff --git a/java/integTest/src/test/java/glide/SharedCommandTests.java b/java/integTest/src/test/java/glide/SharedCommandTests.java
index ab565d1f1e..d0d7e38be3 100644
--- a/java/integTest/src/test/java/glide/SharedCommandTests.java
+++ b/java/integTest/src/test/java/glide/SharedCommandTests.java
@@ -442,6 +442,29 @@ public void hdel_multiple_existing_fields_non_existing_field_non_existing_key(Ba
         assertEquals(0, client.hdel("non_existing_key", new String[] {field3}).get());
     }
 
+    @SneakyThrows
+    @ParameterizedTest
+    @MethodSource("getClients")
+    public void hlen(BaseClient client) {
+        String key1 = UUID.randomUUID().toString();
+        String key2 = UUID.randomUUID().toString();
+        String field1 = UUID.randomUUID().toString();
+        String field2 = UUID.randomUUID().toString();
+        String value = UUID.randomUUID().toString();
+        Map<String, String> fieldValueMap = Map.of(field1, value, field2, value);
+
+        assertEquals(2, client.hset(key1, fieldValueMap).get());
+        assertEquals(2, client.hlen(key1).get());
+        assertEquals(1, client.hdel(key1, new String[] {field1}).get());
+        assertEquals(1, client.hlen(key1).get());
+        assertEquals(0, client.hlen("nonExistingHash").get());
+
+        assertEquals(OK, client.set(key2, "value").get());
+        ExecutionException executionException =
+                assertThrows(ExecutionException.class, () -> client.hlen(key2).get());
+        assertTrue(executionException.getCause() instanceof RequestException);
+    }
+
     @SneakyThrows
     @ParameterizedTest
     @MethodSource("getClients")
diff --git a/java/integTest/src/test/java/glide/TransactionTestUtilities.java b/java/integTest/src/test/java/glide/TransactionTestUtilities.java
index 4c74b4b24d..3ea9091b60 100644
--- a/java/integTest/src/test/java/glide/TransactionTestUtilities.java
+++ b/java/integTest/src/test/java/glide/TransactionTestUtilities.java
@@ -56,6 +56,7 @@ public static BaseTransaction<?> transactionTest(BaseTransaction<?> baseTransact
 
         baseTransaction.hset(key4, Map.of(field1, value1, field2, value2));
         baseTransaction.hget(key4, field1);
+        baseTransaction.hlen(key4);
         baseTransaction.hexists(key4, field2);
         baseTransaction.hmget(key4, new String[] {field1, "non_existing_field", field2});
         baseTransaction.hgetall(key4);
@@ -115,6 +116,7 @@ public static Object[] transactionTestResult() {
             1L,
             2L,
             value1,
+            2L, // hlen(key4)
             true,
             new String[] {value1, null, value2},
             Map.of(field1, value1, field2, value2),