torchvision.datasets.mnist has a broken url in mirrors to download the dataset

[cwestergren]

🐛 Describe the bug

While attempting to download the MNIST dataset using torchvision.datasets.MNIST, I encountered an error that prevents the dataset from downloading successfully. The error indicates an issue with accessing one of the download URLs.

`import torchvision.datasets as datasets
from torch.utils.data import DataLoader

val_ds = datasets.MNIST(root='.', train=False, download=True)
val_dl = DataLoader(val_ds, batch_size=128, shuffle=True)`

Expected Behavior

The MNIST dataset should be downloaded successfully without encountering any HTTP errors.

Actual Behavior

The download fails with a 403 Forbidden error when attempting to access http://yann.lecun.com/exdb/mnist/train-images-idx3-ubyte.gz.

Observations

1. Unencrypted HTTP Resource: The download is attempting to access a resource over HTTP instead of HTTPS, which may not be secure.
2. 403 Forbidden Error: The server is returning a 403 Forbidden error, indicating that access to the resource is not allowed.

It's been this way for some time, so suggest updating the list of mirrors in https://github.com/pytorch/vision/blob/main/torchvision/datasets/mnist.py to not lead to an unsecure/broken endpoint.

mirrors = [ "http://yann.lecun.com/exdb/mnist/", "https://ossci-datasets.s3.amazonaws.com/mnist/", ]

Notably, trying to download the same files directly from @ylecun page https://yann.lecun.com/exdb/mnist/index.html fails with the same error.

Versions

PyTorch version: 2.3.1+cu118
Is debug build: False
CUDA used to build PyTorch: 11.8
ROCM used to build PyTorch: N/A

OS: Microsoft Windows 11 Pro
GCC version: Could not collect
Clang version: Could not collect
CMake version: Could not collect
Libc version: N/A

Python version: 3.12.4 (tags/v3.12.4:8e8a4ba, Jun 6 2024, 19:30:16) [MSC v.1940 64 bit (AMD64)] (64-bit runtime)
Python platform: Windows-11-10.0.22631-SP0
Is CUDA available: True
CUDA runtime version: Could not collect
CUDA_MODULE_LOADING set to: LAZY
GPU models and configuration: GPU 0: NVIDIA GeForce RTX 3070
Nvidia driver version: 556.12
cuDNN version: Could not collect
HIP runtime version: N/A
MIOpen runtime version: N/A
Is XNNPACK available: True

CPU:
Architecture=9
CurrentClockSpeed=3696
DeviceID=CPU0
Family=207
L2CacheSize=2560
L2CacheSpeed=
Manufacturer=GenuineIntel
MaxClockSpeed=3696
Name=Intel(R) Core(TM) i9-10900K CPU @ 3.70GHz
ProcessorType=3
Revision=

Versions of relevant libraries:
[pip3] numpy==1.26.4
[pip3] torch==2.3.1+cu118
[pip3] torchinfo==1.8.0
[pip3] torchvision==0.18.1+cu118
[pip3] torchviz==0.0.2
[conda] Could not collect

[NicolasHug]

Thanks for the report @cwestergren . Yeah, sadly the official MNIST mirror from Lecun is down. And the existing alternative is down too (well, it leads to downloading empty files).

We should try to add alternative mirrors from sources we can trust enough. Happy to consider suggestions.

[SdgJlbl]

Hello, we are using torchvision to load MNIST for our quickstart example, and even having one of the two mirrors down is a problem for us, since it will display 403 Forbidden errors which are confusing for first-time users (see this Slack message for example).
If you find a good alternative mirror, maybe it could be worth deprecating the "official" one (or at least moving it down the list), since it has been down for more than 2 months now.

[GdoongMathew]

Hi @NicolasHug, I think this issue could be closed as well, consider #8752 is solved.