Correct dist.ddp component (#93)

Summary:
Pull Request resolved: #93

Correct dist.ddp component with proper args env and resource

Reviewed By: kiukchung

Differential Revision: D29433684

fbshipit-source-id: 5a439b85f3ef6330f632793008c28dbc299e2899

Author: aivanou

torchx/components/dist.py

@@ -35,7 +35,8 @@ def ddp(
     Args:
         image: container image.
         entrypoint: script or binary to run within the image.
-        resource: Registered named resource.
+        resource: Optional resource identifier. The resource parameter
+            gets ignored when running on the local scheduler.
         nnodes: Number of nodes.
         nproc_per_node: Number of processes per node.
         name: Name of the application.
@@ -56,8 +57,8 @@ def ddp(
         entrypoint=entrypoint,
         resource=resource or specs.NULL_RESOURCE,
         num_replicas=nnodes,
-        script_args=list(script_args),
-        script_envs=env,
+        args=list(script_args),
+        env=env,
         nproc_per_node=nproc_per_node,
         nnodes=nnodes,
         max_restarts=0,