Merge pull request #1813 from weaviate/jose/add_alias_exists

Add support for exists on aliases.

Author: jfrancoa

integration/test_alias.py

@@ -78,8 +78,10 @@ def test_alias_creation_and_deletion(client: weaviate.WeaviateClient, request: S
         assert all_alias[alias2].collection == name2
 
         # Delete existing aliases
-        assert client.alias.delete(alias_name=alias1)
-        assert client.alias.delete(alias_name=alias2)
+        if client.alias.exists(alias_name=alias1):
+            assert client.alias.delete(alias_name=alias1)
+        if client.alias.exists(alias_name=alias2):
+            assert client.alias.delete(alias_name=alias2)
         all_alias = client.alias.list_all(collection=name2)
         all_alias = {
             alias[0]: alias[1]
@@ -157,3 +159,25 @@ def test_alias_get(client: weaviate.WeaviateClient, request: SubRequest) -> None
     finally:
         client.collections.delete(name)
         client.alias.delete(alias_name=alias1)
+
+
+def test_alias_exists(client: weaviate.WeaviateClient, request: SubRequest) -> None:
+    if client._connection._weaviate_version.is_lower_than(1, 32, 0):
+        pytest.skip("Aliases are not supported in Weaviate versions < 1.32.0")
+
+    name = _sanitize_collection_name(request.node.name)
+    alias1: str = "Alias" + _sanitize_collection_name(request.node.name)
+
+    client.collections.delete(name)
+    client.alias.delete(alias_name=alias1)
+    try:
+        client.collections.create(
+            name=name, vectorizer_config=wvc.config.Configure.Vectorizer.none()
+        )
+
+        client.alias.create(alias_name=alias1, target_collection=name)
+        assert client.alias.exists(alias_name=alias1)
+    finally:
+        client.collections.delete(name)
+        client.alias.delete(alias_name=alias1)
+        assert not client.alias.exists(alias_name=alias1)

weaviate/aliases/async_.pyi

@@ -11,3 +11,4 @@ class _AliasAsync(_AliasExecutor[ConnectionAsync]):
     async def create(self, *, alias_name: str, target_collection: str) -> None: ...
     async def delete(self, *, alias_name: str) -> bool: ...
     async def update(self, *, alias_name: str, new_target_collection: str) -> bool: ...
+    async def exists(self, *, alias_name: str) -> bool: ...

weaviate/aliases/executor.py

@@ -122,3 +122,25 @@ def resp(res: Response) -> bool:
                 error="update aliases",
             ),
         )
+
+    def exists(self, *, alias_name: str) -> executor.Result[bool]:
+        """Use this method to check if an alias exists in the Weaviate instance.
+
+        Args:
+            name: The name of the alias to check.
+
+        Returns:
+            `True` if the alias exists, `False` otherwise.
+        """
+        self._connection._weaviate_version.check_is_at_least_1_32_0("alias")
+
+        def resp(res: Response) -> bool:
+            return res.status_code == 200
+
+        return executor.execute(
+            response_callback=resp,
+            method=self._connection.get,
+            path=f"/aliases/{alias_name}",
+            error_msg="Alias may not exist.",
+            status_codes=_ExpectedStatusCodes(ok_in=[200, 404], error="alias exists"),
+        )

weaviate/aliases/sync.pyi

@@ -11,3 +11,4 @@ class _Alias(_AliasExecutor[ConnectionSync]):
     def create(self, *, alias_name: str, target_collection: str) -> None: ...
     def delete(self, *, alias_name: str) -> bool: ...
     def update(self, *, alias_name: str, new_target_collection: str) -> bool: ...
+    def exists(self, *, alias_name: str) -> bool: ...