From e560933f9c0a8b3b4e6ac62228e8dc401646a021 Mon Sep 17 00:00:00 2001
From: architkulkarni <architkulkarni@users.noreply.github.com>
Date: Tue, 12 Jan 2021 09:57:15 -0800
Subject: [PATCH] [Serve] Add dependency management support for driver not
 running in a conda env (#13269)

---
 doc/source/serve/advanced.rst                   |  5 -----
 .../ray/serve/examples/doc/imported_backend.py  |  1 +
 python/ray/serve/utils.py                       | 17 +++++++++++++----
 3 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/doc/source/serve/advanced.rst b/doc/source/serve/advanced.rst
index dc386ee11..4ec71103e 100644
--- a/doc/source/serve/advanced.rst
+++ b/doc/source/serve/advanced.rst
@@ -386,11 +386,6 @@ as shown below.
 
 .. literalinclude:: ../../../python/ray/serve/examples/doc/conda_env.py
 
-.. warning::
-  The script must be run in an activated conda environment (not required to be
-  ``ray-tf1`` or ``ray-tf2``).  We hope to remove this restriction in the
-  future.
-
 .. note::
   If the argument ``env`` is omitted, backends will be started in the same
   conda environment as the caller of
diff --git a/python/ray/serve/examples/doc/imported_backend.py b/python/ray/serve/examples/doc/imported_backend.py
index ec864c211..d80d73b4a 100644
--- a/python/ray/serve/examples/doc/imported_backend.py
+++ b/python/ray/serve/examples/doc/imported_backend.py
@@ -5,6 +5,7 @@ from ray.serve.backends import ImportedBackend
 
 client = serve.start()
 
+# Include your class as input to the ImportedBackend constructor.
 backend_class = ImportedBackend("ray.serve.utils.MockImportedBackend")
 client.create_backend("imported", backend_class, "input_arg")
 client.create_endpoint("imported", backend="imported", route="/imported")
diff --git a/python/ray/serve/utils.py b/python/ray/serve/utils.py
index 7244ca4db..6d15e53fa 100644
--- a/python/ray/serve/utils.py
+++ b/python/ray/serve/utils.py
@@ -11,6 +11,7 @@ from typing import Iterable, List, Dict, Tuple
 import os
 from ray.serve.exceptions import RayServeException
 from collections import UserDict
+from pathlib import Path
 
 import starlette.requests
 import requests
@@ -180,13 +181,21 @@ def format_actor_name(actor_name, controller_name=None, *modifiers):
 
 def get_conda_env_dir(env_name):
     """Given a environment name like `tf1`, find and validate the
-    corresponding conda directory.
+    corresponding conda directory. Untested on Windows.
     """
     conda_prefix = os.environ.get("CONDA_PREFIX")
     if conda_prefix is None:
-        raise ValueError(
-            "Serve cannot find environment variables installed by conda. " +
-            "Are you sure you are in a conda env?")
+        # The caller is neither in a conda env or in (base).  This is rare
+        # because by default, new terminals start in (base), but we can still
+        # support this case.
+        conda_exe = os.environ.get("CONDA_EXE")
+        if conda_exe is None:
+            raise RayServeException(
+                "Ray Serve cannot find environment variables set by conda. "
+                "Please verify conda is installed.")
+        # Example: CONDA_EXE=$HOME/anaconda3/bin/python
+        # Strip out the /bin/python by going up two parent directories.
+        conda_prefix = str(Path(conda_exe).parent.parent)
 
     # There are two cases:
     # 1. We are in conda base env: CONDA_DEFAULT_ENV=base and