Python: adds HSETNX command

CHANGELOG.md

@@ -14,6 +14,7 @@
 * Node: Added ZCOUNT command ([#909](https://github.com/aws/glide-for-redis/pull/909))
 * Python: Added ECHO command ([#953](https://github.com/aws/glide-for-redis/pull/953))
 * Python: Added ZPOPMIN command ([#975](https://github.com/aws/glide-for-redis/pull/975))
+* Python: Added HSETNX command. ([#954](https://github.com/aws/glide-for-redis/pull/954))
 
 #### Features
 * Python, Node: Added support in Lua Scripts ([#775](https://github.com/aws/glide-for-redis/pull/775), [#860](https://github.com/aws/glide-for-redis/pull/860))

glide-core/src/client/value_conversion.rs

@@ -201,7 +201,7 @@ pub(crate) fn expected_type_for_cmd(cmd: &Cmd) -> Option<ExpectedReturnType> {
             Some(ExpectedReturnType::Map)
         }
         b"INCRBYFLOAT" | b"HINCRBYFLOAT" => Some(ExpectedReturnType::Double),
-        b"HEXISTS" | b"EXPIRE" | b"EXPIREAT" | b"PEXPIRE" | b"PEXPIREAT" => {
+        b"HEXISTS" | b"HSETNX" | b"EXPIRE" | b"EXPIREAT" | b"PEXPIRE" | b"PEXPIREAT" => {
             Some(ExpectedReturnType::Boolean)
         }
         b"SMEMBERS" => Some(ExpectedReturnType::Set),

glide-core/src/protobuf/redis_request.proto

@@ -107,6 +107,7 @@ enum RequestType {
     HLen = 69;
     Echo = 70;
     ZPopMin = 71;
+    HSetNX = 72;
 }
 
 message Command {

glide-core/src/socket_listener.rs

@@ -350,6 +350,7 @@ fn get_command(request: &Command) -> Option<Cmd> {
         RequestType::HLen => Some(cmd("HLEN")),
         RequestType::Echo => Some(cmd("ECHO")),
         RequestType::ZPopMin => Some(cmd("ZPOPMIN")),
+        RequestType::HSetNX => Some(cmd("HSETNX")),
     }
 }
 

python/python/glide/async_commands/core.py

@@ -419,7 +419,7 @@ async def hset(self, key: str, field_value_map: Mapping[str, str]) -> int:
             int: The number of fields that were added to the hash.
 
         Example:
-            >>> hset("my_hash", {"field": "value", "field2": "value2"})
+            >>> await client.hset("my_hash", {"field": "value", "field2": "value2"})
                 2
         """
         field_value_list: List[str] = [key]
@@ -444,16 +444,47 @@ async def hget(self, key: str, field: str) -> Optional[str]:
             Returns None if `field` is not presented in the hash or `key` does not exist.
 
         Examples:
-            >>> hget("my_hash", "field")
+            >>> await client.hget("my_hash", "field")
                 "value"
-            >>> hget("my_hash", "nonexistent_field")
+            >>> await client.hget("my_hash", "nonexistent_field")
                 None
         """
         return cast(
             Optional[str],
             await self._execute_command(RequestType.HashGet, [key, field]),
         )
 
+    async def hsetnx(
+        self,
+        key: str,
+        field: str,
+        value: str,
+    ) -> bool:
+        """
+        Sets `field` in the hash stored at `key` to `value`, only if `field` does not yet exist.
+        If `key` does not exist, a new key holding a hash is created.
+        If `field` already exists, this operation has no effect.
+        See https://redis.io/commands/hsetnx/ for more details.
+
+        Args:
+            key (str): The key of the hash.
+            field (str): The field to set the value for.
+            value (str): The value to set.
+
+        Returns:
+            bool: True if the field was set, False if the field already existed and was not set.
+
+        Examples:
+            >>> await client.hsetnx("my_hash", "field", "value")
+                True  # Indicates that the field "field" was set successfully in the hash "my_hash".
+            >>> await client.hsetnx("my_hash", "field", "new_value")
+                False # Indicates that the field "field" already existed in the hash "my_hash" and was not set again.
+        """
+        return cast(
+            bool,
+            await self._execute_command(RequestType.HSetNX, [key, field, value]),
+        )
+
     async def hincrby(self, key: str, field: str, amount: int) -> int:
         """
         Increment or decrement the value of a `field` in the hash stored at `key` by the specified amount.

python/python/glide/async_commands/transaction.py

@@ -373,6 +373,28 @@ def hget(self: TTransaction, key: str, field: str) -> TTransaction:
         """
         return self.append_command(RequestType.HashGet, [key, field])
 
+    def hsetnx(
+        self: TTransaction,
+        key: str,
+        field: str,
+        value: str,
+    ) -> TTransaction:
+        """
+        Sets `field` in the hash stored at `key` to `value`, only if `field` does not yet exist.
+        If `key` does not exist, a new key holding a hash is created.
+        If `field` already exists, this operation has no effect.
+        See https://redis.io/commands/hsetnx/ for more details.
+
+        Args:
+            key (str): The key of the hash.
+            field (str): The field to set the value for.
+            value (str): The value to set.
+
+        Commands response:
+            bool: True if the field was set, False if the field already existed and was not set.
+        """
+        return self.append_command(RequestType.HSetNX, [key, field, value])
+
     def hincrby(self: TTransaction, key: str, field: str, amount: int) -> TTransaction:
         """
         Increment or decrement the value of a `field` in the hash stored at `key` by the specified amount.

python/python/tests/test_async_client.py

@@ -634,6 +634,20 @@ async def test_hdel(self, redis_client: TRedisClient):
         assert await redis_client.hdel(key, ["nonExistingField"]) == 0
         assert await redis_client.hdel("nonExistingKey", [field3]) == 0
 
+    @pytest.mark.parametrize("cluster_mode", [True, False])
+    @pytest.mark.parametrize("protocol", [ProtocolVersion.RESP2, ProtocolVersion.RESP3])
+    async def test_hsetnx(self, redis_client: TRedisClient):
+        key = get_random_string(10)
+        field = get_random_string(5)
+
+        assert await redis_client.hsetnx(key, field, "value") == True
+        assert await redis_client.hsetnx(key, field, "new value") == False
+        assert await redis_client.hget(key, field) == "value"
+        key = get_random_string(5)
+        assert await redis_client.set(key, "value") == OK
+        with pytest.raises(RequestError):
+            await redis_client.hsetnx(key, field, "value")
+
     @pytest.mark.parametrize("cluster_mode", [True, False])
     @pytest.mark.parametrize("protocol", [ProtocolVersion.RESP2, ProtocolVersion.RESP3])
     async def test_hmget(self, redis_client: TRedisClient):

python/python/tests/test_transaction.py

@@ -86,7 +86,8 @@ def transaction_test(
     args.append(value2)
     transaction.hlen(key4)
     args.append(2)
-
+    transaction.hsetnx(key4, key, value)
+    args.append(False)
     transaction.hincrby(key4, key3, 5)
     args.append(5)
     transaction.hincrbyfloat(key4, key3, 5.5)