feat(document status): support external id and instance id for streaming

Author: andersfylling

cognite/client/_api/documents.py

@@ -514,7 +514,13 @@ def retrieve_content(
         response = self._do_request("POST", f"{self._RESOURCE_PATH}/content", accept="text/plain", json=identifier)
         return response.content
 
-    def retrieve_content_buffer(self, id: int, buffer: BinaryIO) -> None:
+    def retrieve_content_buffer(
+        self,
+        buffer: BinaryIO,
+        id: int | None = None,
+        external_id: str | None = None,
+        instance_id: NodeId | None = None,
+    ) -> None:
         """`Retrieve document content into buffer <https://developer.cognite.com/api#tag/Documents/operation/documentsContent>`_
 
         Returns extracted textual information for the given document.
@@ -526,8 +532,10 @@ def retrieve_content_buffer(self, id: int, buffer: BinaryIO) -> None:
 
 
         Args:
-            id (int): The server-generated ID for the document you want to retrieve the content of.
             buffer (BinaryIO): The document content is streamed directly into the buffer. This is useful for retrieving large documents.
+            id (int | None): The server-generated ID for the document you want to retrieve the content of.
+            external_id (str | None): External ID
+            instance_id (NodeId | None): Instance ID
 
         Examples:
 
@@ -539,8 +547,10 @@ def retrieve_content_buffer(self, id: int, buffer: BinaryIO) -> None:
                 >>> with Path("my_file.txt").open("wb") as buffer:
                 ...     client.documents.retrieve_content_buffer(id=123, buffer=buffer)
         """
+        identifiers = IdentifierSequence.load(ids=id, external_ids=external_id, instance_ids=instance_id).as_singleton()
+        identifier = identifiers.as_dicts()[0]
         with self._do_request(
-            "POST", f"{self._RESOURCE_PATH}/content", stream=True, accept="text/plain", json={"id": id}
+            "POST", f"{self._RESOURCE_PATH}/content", stream=True, accept="text/plain", json=identifier
         ) as response:
             for chunk in response.iter_content(chunk_size=2**21):
                 if chunk:  # filter out keep-alive new chunks