Merge branch 'nc/playground' of https://github.com/langchain-ai/langs…

…erve into nc/playground

langserve/playground.py

@@ -2,33 +2,46 @@
 import mimetypes
 import os
 from string import Template
-from typing import List
+from typing import List, Type
 
 from fastapi.responses import Response
 from langchain.schema.runnable import Runnable
 
+try:
+    from pydantic.v1 import BaseModel
+except ImportError:
+    from pydantic import BaseModel
+
 
 class PlaygroundTemplate(Template):
     delimiter = "____"
 
 
 async def serve_playground(
-    runnable: Runnable, config_keys: List[str], base_url: str, file_path: str
+    runnable: Runnable,
+    input_schema: Type[BaseModel],
+    config_keys: List[str],
+    base_url: str,
+    file_path: str,
 ) -> Response:
     local_file_path = os.path.join(
         os.path.dirname(__file__),
         "./playground/dist",
         file_path or "index.html",
     )
     with open(local_file_path) as f:
-        html = f.read()
         mime_type = mimetypes.guess_type(local_file_path)[0]
-    formatted = PlaygroundTemplate(html).substitute(
-        LANGSERVE_BASE_URL=base_url[1:] if base_url.startswith("/") else base_url,
-        LANGSERVE_CONFIG_SCHEMA=json.dumps(
-            runnable.config_schema(include=config_keys).schema()
-        ),
-        LANGSERVE_INPUT_SCHEMA=json.dumps(runnable.input_schema.schema()),
-    )
+        if mime_type in ("text/html", "text/css", "application/javascript"):
+            res = PlaygroundTemplate(f.read()).substitute(
+                LANGSERVE_BASE_URL=base_url[1:]
+                if base_url.startswith("/")
+                else base_url,
+                LANGSERVE_CONFIG_SCHEMA=json.dumps(
+                    runnable.config_schema(include=config_keys).schema()
+                ),
+                LANGSERVE_INPUT_SCHEMA=json.dumps(input_schema.schema()),
+            )
+        else:
+            res = f.buffer.read()
 
-    return Response(formatted, media_type=mime_type)
+    return Response(res, media_type=mime_type)