fetch_openml() does not use the local cache #12227
Description
Description
fetch_openml() does not use the local data cached in ~/scikit_learn_data.
Steps/Code to Reproduce
Run the following code twice. The first time, with a working Internet connexion, the second time without an Internet connexion.
from sklearn.datasets import fetch_openml
mnist = fetch_openml("mnist_784", version=1)
print(mnist.data.shape)Expected Results
First run (with Internet access):
(70000, 784)
Second run (without Internet access):
(70000, 784)
Actual Results
First run (with Internet access):
(70000, 784)
Second run (without Internet access):
Traceback (most recent call last):
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1318, in do_open
encode_chunked=req.has_header('Transfer-encoding'))
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1239, in request
self._send_request(method, url, body, headers, encode_chunked)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1285, in _send_request
self.endheaders(body, encode_chunked=encode_chunked)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1234, in endheaders
self._send_output(message_body, encode_chunked=encode_chunked)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1026, in _send_output
self.send(msg)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 964, in send
self.connect()
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1392, in connect
super().connect()
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 936, in connect
(self.host,self.port), self.timeout, self.source_address)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/socket.py", line 704, in create_connection
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/socket.py", line 745, in getaddrinfo
for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno 8] nodename nor servname provided, or not known
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/ageron/.virtualenvs/ml/lib/python3.6/site-packages/sklearn/datasets/openml.py", line 466, in fetch_openml
data_info = _get_data_info_by_name(name, version, data_home)
File "/Users/ageron/.virtualenvs/ml/lib/python3.6/site-packages/sklearn/datasets/openml.py", line 275, in _get_data_info_by_name
data_home)
File "/Users/ageron/.virtualenvs/ml/lib/python3.6/site-packages/sklearn/datasets/openml.py", line 119, in _get_json_content_from_openml_api
response = _open_openml_url(url, data_home)
File "/Users/ageron/.virtualenvs/ml/lib/python3.6/site-packages/sklearn/datasets/openml.py", line 55, in _open_openml_url
fsrc = urlopen(req)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 223, in urlopen
return opener.open(url, data, timeout)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 526, in open
response = self._open(req, data)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 544, in _open
'_open', req)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 504, in _call_chain
result = func(*args)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1361, in https_open
context=self._context, check_hostname=self._check_hostname)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1320, in do_open
raise URLError(err)
urllib.error.URLError: <urlopen error [Errno 8] nodename nor servname provided, or not known>
AFAICT, the data is correctly cached in the ~/scikit_learn_data directory, but simply ignored by fetch_openml():
$ tree ~/scikit_learn_data/openml/
/Users/ageron/scikit_learn_data/openml/
└── openml.org
├── api
│ └── v1
│ └── json
│ └── data
│ ├── 554.gz
│ ├── features
│ │ └── 554.gz
│ └── list
│ └── data_name
│ └── mnist_784
│ └── limit
│ └── 2
│ └── data_version
│ └── 1.gz
└── data
└── v1
└── download
└── 52667.gz
15 directories, 4 filesVersions
Darwin-17.7.0-x86_64-i386-64bit
Python 3.6.6 (default, Jun 28 2018, 05:43:53)
[GCC 4.2.1 Compatible Apple LLVM 9.1.0 (clang-902.0.39.2)]
NumPy 1.15.2
SciPy 1.1.0
Scikit-Learn 0.20.0
Same results as well on:
Linux-4.15.0-36-generic-x86_64-with-Ubuntu-18.04-bionic
Python 3.6.5 (default, Apr 1 2018, 05:46:30)
[GCC 7.3.0]
NumPy 1.15.1
SciPy 1.1.0
Scikit-Learn 0.20.0