Remove deprecated/unused functions from datasets.utils (#2926)

Summary:
`stream_url`, `download_url` and `validate_file` are not used and not listed in documentation (`download_url` is marked as deprecated) so remove them.

This will also fix the failing bandit workflow.

Pull Request resolved: https://github.com/pytorch/audio/pull/2926

Reviewed By: carolineechen

Differential Revision: D42153484

Pulled By: mthrok

fbshipit-source-id: 0fccdc7b7e0e40db8046e12f46eb68de57d838ca

torchaudio/datasets/utils.py

-import hashlib
 import logging
 import os
 import tarfile
-import urllib
-import urllib.request
-import warnings
 import zipfile
-from typing import Any, Iterable, List, Optional
+from typing import Any, List, Optional
 
 import torchaudio
 
-from torch.utils.model_zoo import tqdm
-
-
-def stream_url(
-    url: str, start_byte: Optional[int] = None, block_size: int = 32 * 1024, progress_bar: bool = True
-) -> Iterable:
-    """Stream url by chunk
-
-    Args:
-        url (str): Url.
-        start_byte (int or None, optional): Start streaming at that point (Default: ``None``).
-        block_size (int, optional): Size of chunks to stream (Default: ``32 * 1024``).
-        progress_bar (bool, optional): Display a progress bar (Default: ``True``).
-    """
-
-    # If we already have the whole file, there is no need to download it again
-    req = urllib.request.Request(url, method="HEAD")
-    with urllib.request.urlopen(req) as response:
-        url_size = int(response.info().get("Content-Length", -1))
-    if url_size == start_byte:
-        return
-
-    req = urllib.request.Request(url)
-    if start_byte:
-        req.headers["Range"] = "bytes={}-".format(start_byte)
-
-    with urllib.request.urlopen(req) as upointer, tqdm(
-        unit="B",
-        unit_scale=True,
-        unit_divisor=1024,
-        total=url_size,
-        disable=not progress_bar,
-    ) as pbar:
-
-        num_bytes = 0
-        while True:
-            chunk = upointer.read(block_size)
-            if not chunk:
-                break
-            yield chunk
-            num_bytes += len(chunk)
-            pbar.update(len(chunk))
-
-
-def download_url(
-    url: str,
-    download_folder: str,
-    filename: Optional[str] = None,
-    hash_value: Optional[str] = None,
-    hash_type: str = "sha256",
-    progress_bar: bool = True,
-    resume: bool = False,
-) -> None:
-    """Download file to disk.
-
-    Args:
-        url (str): Url.
-        download_folder (str): Folder to download file.
-        filename (str or None, optional): Name of downloaded file. If None, it is inferred from the url
-            (Default: ``None``).
-        hash_value (str or None, optional): Hash for url (Default: ``None``).
-        hash_type (str, optional): Hash type, among "sha256" and "md5" (Default: ``"sha256"``).
-        progress_bar (bool, optional): Display a progress bar (Default: ``True``).
-        resume (bool, optional): Enable resuming download (Default: ``False``).
-    """
-    warnings.warn("download_url is deprecated and will be removed in the v0.12 release.")
-    req = urllib.request.Request(url, method="HEAD")
-    req_info = urllib.request.urlopen(req).info()
-
-    # Detect filename
-    filename = filename or req_info.get_filename() or os.path.basename(url)
-    filepath = os.path.join(download_folder, filename)
-    if resume and os.path.exists(filepath):
-        mode = "ab"
-        local_size: Optional[int] = os.path.getsize(filepath)
-
-    elif not resume and os.path.exists(filepath):
-        raise RuntimeError("{} already exists. Delete the file manually and retry.".format(filepath))
-    else:
-        mode = "wb"
-        local_size = None
-
-    if hash_value and local_size == int(req_info.get("Content-Length", -1)):
-        with open(filepath, "rb") as file_obj:
-            if validate_file(file_obj, hash_value, hash_type):
-                return
-        raise RuntimeError("The hash of {} does not match. Delete the file manually and retry.".format(filepath))
-
-    with open(filepath, mode) as fpointer:
-        for chunk in stream_url(url, start_byte=local_size, progress_bar=progress_bar):
-            fpointer.write(chunk)
-
-    with open(filepath, "rb") as file_obj:
-        if hash_value and not validate_file(file_obj, hash_value, hash_type):
-            raise RuntimeError("The hash of {} does not match. Delete the file manually and retry.".format(filepath))
-
-
-def validate_file(file_obj: Any, hash_value: str, hash_type: str = "sha256") -> bool:
-    """Validate a given file object with its hash.
-
-    Args:
-        file_obj: File object to read from.
-        hash_value (str): Hash for url.
-        hash_type (str, optional): Hash type, among "sha256" and "md5" (Default: ``"sha256"``).
-
-    Returns:
-        bool: return True if its a valid file, else False.
-    """
-
-    if hash_type == "sha256":
-        hash_func = hashlib.sha256()
-    elif hash_type == "md5":
-        hash_func = hashlib.md5()
-    else:
-        raise ValueError
-
-    while True:
-        # Read by chunk to avoid filling memory
-        chunk = file_obj.read(1024**2)
-        if not chunk:
-            break
-        hash_func.update(chunk)
-
-    return hash_func.hexdigest() == hash_value
-
 
 def extract_archive(from_path: str, to_path: Optional[str] = None, overwrite: bool = False) -> List[str]:
     """Extract archive.