Finish extracting _open_file()

Summary: Finish extracting _open_file() to a separate utils module (started with D20754859 (https://github.com/facebookresearch/pytorch3d/commit/c9267ab7af0f72217a1ee1a0b37941a5c8fdb325) / previous version of this diff).

Reviewed By: nikhilaravi

Differential Revision: D20720344

fbshipit-source-id: 77ef201ff37a8f2a0cd19be162cb97ee99480158

pytorch3d/io/obj_io.py

@@ -3,7 +3,6 @@
 
 """This module implements utility functions for loading and saving meshes."""
 import os
-import pathlib
 import warnings
 from collections import namedtuple
 from typing import Optional
@@ -216,7 +215,7 @@ def load_obj(
         # pyre-fixme[6]: Expected `_PathLike[Variable[typing.AnyStr <: [str,
         #  bytes]]]` for 1st param but got `Union[_PathLike[typing.Any], bytes, str]`.
         data_dir = os.path.dirname(f_obj)
-    f_obj, new_f = _open_file(f_obj)
+    f_obj, new_f = _open_file(f_obj, "r")
     try:
         return _load(
             f_obj,
@@ -524,13 +523,7 @@ def save_obj(f, verts, faces, decimal_places: Optional[int] = None):
         message = "Argument 'faces' should either be empty or of shape (num_faces, 3)."
         raise ValueError(message)
 
-    new_f = False
-    if isinstance(f, str):
-        new_f = True
-        f = open(f, "w")
-    elif isinstance(f, pathlib.Path):
-        new_f = True
-        f = f.open("w")
+    f, new_f = _open_file(f, "w")
     try:
         return _save(f, verts, faces, decimal_places)
     finally:

pytorch3d/io/ply_io.py

@@ -4,7 +4,6 @@
 
 
 """This module implements utility functions for loading and saving meshes."""
-import pathlib
 import struct
 import sys
 import warnings
@@ -13,6 +12,7 @@ from typing import Optional, Tuple
 
 import numpy as np
 import torch
+from pytorch3d.io.utils import _open_file
 
 
 _PlyTypeData = namedtuple("_PlyTypeData", "size struct_char np_type")
@@ -603,13 +603,7 @@ def _load_ply_raw(f) -> Tuple[_PlyHeader, dict]:
                   uniformly-sized list, then the value will be a 2D numpy array.
                   If not, it is a list of the relevant property values.
     """
-    new_f = False
-    if isinstance(f, str):
-        new_f = True
-        f = open(f, "rb")
-    elif isinstance(f, pathlib.Path):
-        new_f = True
-        f = f.open("rb")
+    f, new_f = _open_file(f, "rb")
     try:
         header, elements = _load_ply_raw_stream(f)
     finally:
@@ -806,13 +800,7 @@ def save_ply(
         message = "Argument 'verts_normals' should either be empty or of shape (num_verts, 3)."
         raise ValueError(message)
 
-    new_f = False
-    if isinstance(f, str):
-        new_f = True
-        f = open(f, "w")
-    elif isinstance(f, pathlib.Path):
-        new_f = True
-        f = f.open("w")
+    f, new_f = _open_file(f, "w")
     try:
         _save_ply(f, verts, faces, verts_normals, decimal_places)
     finally:

pytorch3d/io/utils.py

@@ -7,14 +7,15 @@ from fvcore.common.file_io import PathManager
 from PIL import Image
 
 
-def _open_file(f):
+# TODO(plabatut): Replace with a context manager
+def _open_file(f, mode="r"):
     new_f = False
     if isinstance(f, str):
         new_f = True
-        f = open(f, "r")
+        f = open(f, mode)
     elif isinstance(f, pathlib.Path):
         new_f = True
-        f = f.open("r")
+        f = f.open(mode)
     return f, new_f