Add support for EXPIRE command's options (#2002)

* Add support for EXPIRE command's options

* Add requested changes

* Change method arguments

* add variables to the function header

Co-authored-by: dvora-h <67596500+dvora-h@users.noreply.github.com>
Co-authored-by: Chayim <chayim@users.noreply.github.com>
Co-authored-by: dvora-h <dvora.heller@redis.com>

redis/commands/core.py

@@ -1501,16 +1501,42 @@ def exists(self, *names: KeyT) -> ResponseT:
 
     __contains__ = exists
 
-    def expire(self, name: KeyT, time: ExpiryT) -> ResponseT:
+    def expire(
+        self,
+        name: KeyT,
+        time: ExpiryT,
+        nx: bool = False,
+        xx: bool = False,
+        gt: bool = False,
+        lt: bool = False,
+    ) -> ResponseT:
         """
-        Set an expire flag on key ``name`` for ``time`` seconds. ``time``
-        can be represented by an integer or a Python timedelta object.
+        Set an expire flag on key ``name`` for ``time`` seconds with given
+        ``option``. ``time`` can be represented by an integer or a Python timedelta
+        object.
+
+        Valid options are:
+            NX -> Set expiry only when the key has no expiry
+            XX -> Set expiry only when the key has an existing expiry
+            GT -> Set expiry only when the new expiry is greater than current one
+            LT -> Set expiry only when the new expiry is less than current one
 
         For more information check https://redis.io/commands/expire
         """
         if isinstance(time, datetime.timedelta):
             time = int(time.total_seconds())
-        return self.execute_command("EXPIRE", name, time)
+
+        exp_option = list()
+        if nx:
+            exp_option.append("NX")
+        if xx:
+            exp_option.append("XX")
+        if gt:
+            exp_option.append("GT")
+        if lt:
+            exp_option.append("LT")
+
+        return self.execute_command("EXPIRE", name, time, *exp_option)
 
     def expireat(self, name: KeyT, when: AbsExpiryT) -> ResponseT:
         """

tests/test_commands.py

@@ -1058,6 +1058,31 @@ def test_expire(self, r):
         assert r.persist("a")
         assert r.ttl("a") == -1
 
+    @skip_if_server_version_lt("7.0.0")
+    def test_expire_option_nx(self, r):
+        r.set("key", "val")
+        assert r.expire("key", 100, nx=True) == 1
+        assert r.expire("key", 500, nx=True) == 0
+
+    @skip_if_server_version_lt("7.0.0")
+    def test_expire_option_xx(self, r):
+        r.set("key", "val")
+        assert r.expire("key", 100, xx=True) == 0
+        assert r.expire("key", 100)
+        assert r.expire("key", 500, nx=True) == 1
+
+    @skip_if_server_version_lt("7.0.0")
+    def test_expire_option_gt(self, r):
+        r.set("key", "val", 100)
+        assert r.expire("key", 50, gt=True) == 0
+        assert r.expire("key", 500, gt=True) == 1
+
+    @skip_if_server_version_lt("7.0.0")
+    def test_expire_option_lt(self, r):
+        r.set("key", "val", 100)
+        assert r.expire("key", 50, lt=True) == 1
+        assert r.expire("key", 150, lt=True) == 0
+
     def test_expireat_datetime(self, r):
         expire_at = redis_server_time(r) + datetime.timedelta(minutes=1)
         r["a"] = "foo"