Merge pull request #172 from redis/add-expire-#171

Add expire behavior

README.md

@@ -119,6 +119,9 @@ print(andrew.pk)
 # We can save the model to Redis by calling `save()`:
 andrew.save()
 
+# Expire the model after 2 mins (120 seconds)
+andrew.expire(120)
+
 # To retrieve this customer with its primary key, we use `Customer.get()`:
 assert Customer.get(andrew.pk) == andrew
 ```

aredis_om/model/model.py

@@ -1130,6 +1130,15 @@ class RedisModel(BaseModel, abc.ABC, metaclass=ModelMeta):
     async def save(self, pipeline: Optional[Pipeline] = None) -> "RedisModel":
         raise NotImplementedError
 
+    async def expire(self, num_seconds: int, pipeline: Optional[Pipeline] = None):
+        if pipeline is None:
+            db = self.db()
+        else:
+            db = pipeline
+
+        # TODO: Wrap any Redis response errors in a custom exception?
+        await db.expire(self.make_primary_key(self.pk), num_seconds)
+
     @validator("pk", always=True, allow_reuse=True)
     def validate_pk(cls, v):
         if not v:

docs/getting_started.md

@@ -553,6 +553,15 @@ andrew = Customer(
 andrew.save()
 ```
 
+## Expiring Models
+
+We can expire an instance of a model using `expire`, and passing it the number of seconds after which we want the instance to expire in Redis:
+
+```python
+# Expire Andrew in 2 minutes (120 seconds)
+andrew.expire(120)
+```
+
 ## Examining Your Data In Redis
 
 You can view the data stored in Redis for any Redis OM model.

tests/test_hash_model.py

@@ -391,6 +391,24 @@ async def test_delete(m):
     assert response == 1
 
 
+@pytest.mark.asyncio
+async def test_expire(m):
+    member = m.Member(
+        first_name="Expire",
+        last_name="Test",
+        email="e@example.com",
+        join_date=today,
+        age=93,
+        bio="This is a test user for expiry",
+    )
+
+    await member.save()
+    await member.expire(60)
+
+    ttl = await m.Member.db().ttl(member.key())
+    assert ttl > 0
+
+
 def test_raises_error_with_embedded_models(m):
     class Address(m.BaseHashModel):
         address_line_1: str