support confirming no virus scan on GDrive download (#5645)

* support confirming no virus scan on GDrive download

* put gen_bar_updater back

* Update torchvision/datasets/utils.py
Co-authored-by: Nicolas Hug <contact@nicolas-hug.com>
Co-authored-by: Nicolas Hug <contact@nicolas-hug.com>

torchvision/datasets/utils.py

@@ -11,6 +11,7 @@ import tarfile
 import urllib
 import urllib.error
 import urllib.request
+import warnings
 import zipfile
 from typing import Any, Callable, List, Iterable, Optional, TypeVar, Dict, IO, Tuple, Iterator
 from urllib.parse import urlparse
@@ -24,22 +25,31 @@ from .._internally_replaced_utils import (
     _is_remote_location_available,
 )
 
-
 USER_AGENT = "pytorch/vision"
 
 
-def _urlretrieve(url: str, filename: str, chunk_size: int = 1024) -> None:
-    with open(filename, "wb") as fh:
-        with urllib.request.urlopen(urllib.request.Request(url, headers={"User-Agent": USER_AGENT})) as response:
-            with tqdm(total=response.length) as pbar:
-                for chunk in iter(lambda: response.read(chunk_size), ""):
+def _save_response_content(
+    content: Iterator[bytes],
+    destination: str,
+    length: Optional[int] = None,
+) -> None:
+    with open(destination, "wb") as fh, tqdm(total=length) as pbar:
+        for chunk in content:
+            # filter out keep-alive new chunks
             if not chunk:
-                        break
-                    pbar.update(chunk_size)
+                continue
+
             fh.write(chunk)
+            pbar.update(len(chunk))
+
+
+def _urlretrieve(url: str, filename: str, chunk_size: int = 1024 * 32) -> None:
+    with urllib.request.urlopen(urllib.request.Request(url, headers={"User-Agent": USER_AGENT})) as response:
+        _save_response_content(iter(lambda: response.read(chunk_size), b""), filename, length=response.length)
 
 
 def gen_bar_updater() -> Callable[[int, int, int], None]:
+    warnings.warn("The function `gen_bar_update` is deprecated since 0.13 and will be removed in 0.15.")
     pbar = tqdm(total=None)
 
     def bar_update(count, block_size, total_size):
@@ -184,11 +194,20 @@ def list_files(root: str, suffix: str, prefix: bool = False) -> List[str]:
     return files
 
 
-def _quota_exceeded(first_chunk: bytes) -> bool:
+def _extract_gdrive_api_response(response, chunk_size: int = 32 * 1024) -> Tuple[bytes, Iterator[bytes]]:
+    content = response.iter_content(chunk_size)
+    first_chunk = None
+    # filter out keep-alive new chunks
+    while not first_chunk:
+        first_chunk = next(content)
+    content = itertools.chain([first_chunk], content)
+
     try:
-        return "Google Drive - Quota exceeded" in first_chunk.decode()
+        match = re.search("<title>Google Drive - (?P<api_response>.+?)</title>", first_chunk.decode())
+        api_response = match["api_response"] if match is not None else None
     except UnicodeDecodeError:
-        return False
+        api_response = None
+    return api_response, content
 
 
 def download_file_from_google_drive(file_id: str, root: str, filename: Optional[str] = None, md5: Optional[str] = None):
@@ -202,8 +221,6 @@ def download_file_from_google_drive(file_id: str, root: str, filename: Optional[
     """
     # Based on https://stackoverflow.com/questions/38511444/python-download-files-from-google-drive-using-url
 
-    url = "https://docs.google.com/uc?export=download"
-
     root = os.path.expanduser(root)
     if not filename:
         filename = file_id
@@ -211,61 +228,34 @@ def download_file_from_google_drive(file_id: str, root: str, filename: Optional[
 
     os.makedirs(root, exist_ok=True)
 
-    if os.path.isfile(fpath) and check_integrity(fpath, md5):
-        print("Using downloaded and verified file: " + fpath)
-    else:
-        session = requests.Session()
-
-        response = session.get(url, params={"id": file_id}, stream=True)
-        token = _get_confirm_token(response)
+    if check_integrity(fpath, md5):
+        print(f"Using downloaded {'and verified ' if md5 else ''}file: {fpath}")
 
-        if token:
-            params = {"id": file_id, "confirm": token}
+    url = "https://drive.google.com/uc"
+    params = dict(id=file_id, export="download")
+    with requests.Session() as session:
         response = session.get(url, params=params, stream=True)
 
-        # Ideally, one would use response.status_code to check for quota limits, but google drive is not consistent
-        # with their own API, refer https://github.com/pytorch/vision/issues/2992#issuecomment-730614517.
-        # Should this be fixed at some place in future, one could refactor the following to no longer rely on decoding
-        # the first_chunk of the payload
-        response_content_generator = response.iter_content(32768)
-        first_chunk = None
-        while not first_chunk:  # filter out keep-alive new chunks
-            first_chunk = next(response_content_generator)
+        for key, value in response.cookies.items():
+            if key.startswith("download_warning"):
+                token = value
+                break
+        else:
+            api_response, content = _extract_gdrive_api_response(response)
+            token = "t" if api_response == "Virus scan warning" else None
+
+        if token is not None:
+            response = session.get(url, params=dict(params, confirm=token), stream=True)
+            api_response, content = _extract_gdrive_api_response(response)
 
-        if _quota_exceeded(first_chunk):
-            msg = (
+        if api_response == "Quota exceeded":
+            raise RuntimeError(
                 f"The daily quota of the file {filename} is exceeded and it "
                 f"can't be downloaded. This is a limitation of Google Drive "
                 f"and can only be overcome by trying again later."
             )
-            raise RuntimeError(msg)
-
-        _save_response_content(itertools.chain((first_chunk,), response_content_generator), fpath)
-        response.close()
-
 
-def _get_confirm_token(response: requests.models.Response) -> Optional[str]:
-    for key, value in response.cookies.items():
-        if key.startswith("download_warning"):
-            return value
-
-    return None
-
-
-def _save_response_content(
-    response_gen: Iterator[bytes],
-    destination: str,
-) -> None:
-    with open(destination, "wb") as f:
-        pbar = tqdm(total=None)
-        progress = 0
-
-        for chunk in response_gen:
-            if chunk:  # filter out keep-alive new chunks
-                f.write(chunk)
-                progress += len(chunk)
-                pbar.update(progress - pbar.n)
-        pbar.close()
+        _save_response_content(content, fpath)
 
 
 def _extract_tar(from_path: str, to_path: str, compression: Optional[str]) -> None: