Expose httpx auth kwargs to RemoteRunnable to support most authentica…

…tion methods.

langserve/client.py

@@ -15,6 +15,8 @@
 from urllib.parse import urljoin
 
 import httpx
+from httpx._types import CertTypes, CookieTypes, HeaderTypes, VerifyTypes, AuthTypes
+
 from langchain.callbacks.tracers.log_stream import RunLog, RunLogPatch
 from langchain.load.dump import dumpd
 from langchain.schema.runnable import Runnable
@@ -110,16 +112,42 @@ def __init__(
         url: str,
         *,
         timeout: Optional[float] = None,
+        auth: Optional[AuthTypes] = None,
+        headers: Optional[HeaderTypes] = None,
+        cookies: Optional[CookieTypes] = None,
+        verify: VerifyTypes = True,
+        cert: Optional[CertTypes] = None,
     ) -> None:
         """Initialize the client.
 
         Args:
             url: The url of the server
             timeout: The timeout for requests
+            auth: Authentication class for requests
+            headers: Headers to send with requests
+            cookies: Cookies to send with requests
+            verify: Whether to verify SSL certificates
+            cert: SSL certificate to use for requests
         """
         self.url = url
-        self.sync_client = httpx.Client(base_url=url, timeout=timeout)
-        self.async_client = httpx.AsyncClient(base_url=url, timeout=timeout)
+        self.sync_client = httpx.Client(
+            base_url=url,
+            timeout=timeout,
+            auth=auth,
+            headers=headers,
+            cookies=cookies,
+            verify=verify,
+            cert=cert,
+        )
+        self.async_client = httpx.AsyncClient(
+            base_url=url,
+            timeout=timeout,
+            auth=auth,
+            headers=headers,
+            cookies=cookies,
+            verify=verify,
+            cert=cert
+        )
 
         # Register cleanup handler once RemoteRunnable is garbage collected
         weakref.finalize(self, _close_clients, self.sync_client, self.async_client)