fix: add_special_tokens in tokenize (#144)

#66 made add_special_tokens true by default but its behaviour isn't replicated in /tokenize resulting in a different token count if ADD_SPECIAL_TOKENS is false. This PR fixes that by passing it in /tokenize and adds a test for the tokenize method.

I can follow this up with another test that compares the token count between the methods if required but otherwise this closes #141.

src/vllm_tgis_adapter/grpc/grpc_server.py

@@ -855,7 +855,9 @@ async def Tokenize(
         # other threads
         for req in request.requests:
             batch_encoding = tokenizer.encode_plus(
-                text=req.text, return_offsets_mapping=request.return_offsets
+                text=req.text,
+                return_offsets_mapping=request.return_offsets,
+                add_special_tokens=ADD_SPECIAL_TOKENS,
             )
 
             # Tokenize the input text

tests/test_grpc_server.py

@@ -25,6 +25,14 @@ def test_generation_request(grpc_client):
     assert response.stop_reason is not None
 
 
+def test_tokenize_request(grpc_client):
+    response_tokenize = grpc_client.make_request_tokenize(
+        text="Please answer the following question.\nhow far is Paris from New York?",
+    )
+
+    assert response_tokenize.token_count
+
+
 def test_generation_request_stream(grpc_client):
     streaming_response = grpc_client.make_request_stream(
         "The answer to life the universe and everything is ",

tests/utils.py

@@ -11,11 +11,13 @@
 
 from vllm_tgis_adapter.grpc.pb.generation_pb2 import (
     BatchedGenerationRequest,
+    BatchedTokenizeRequest,
     GenerationRequest,
     ModelInfoRequest,
     Parameters,
     SingleGenerationRequest,
     StoppingCriteria,
+    TokenizeRequest,
 )
 from vllm_tgis_adapter.grpc.pb.generation_pb2_grpc import GenerationServiceStub
 
@@ -25,6 +27,7 @@
     from vllm_tgis_adapter.grpc.pb.generation_pb2 import (
         GenerationResponse,
         ModelInfoResponse,
+        TokenizeResponse,
     )
 
 _T = TypeVar("_T")
@@ -173,6 +176,30 @@ def make_request_stream(
         except grpc._channel._MultiThreadedRendezvous as exc:  # noqa: SLF001
             raise RuntimeError(exc.details()) from exc
 
+    def make_request_tokenize(
+        self,
+        text: str | list[str],
+        model_id: str | None = None,
+        adapter_id: str | None = None,
+    ) -> TokenizeResponse | Sequence[TokenizeResponse]:
+        if single_request := isinstance(text, str):
+            text = [text]
+
+        request = BatchedTokenizeRequest(
+            model_id=model_id,
+            requests=[TokenizeRequest(text=piece) for piece in text],
+            adapter_id=adapter_id,
+        )
+
+        response = self.generation_service_stub.Tokenize(
+            request=request,
+        )
+
+        if single_request:
+            return response.responses[0]
+
+        return response.responses
+
     def __enter__(self):  # noqa: D105
         return self