Will clean up release notes later, highlights:

• Fix usage of environment variables for locating the default cache and configuration directories by @eddiebergman in #1359
• Allow skip trying to download parquet files by setting the OPENML_SKIP_PARQUET variable to true by @PGijsbers in #1388
• a lot of maintenance work by @eddiebergman and @LennartPurucker

Thanks to everyone who contributed in any way ❤️

What's Changed

• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #1329
• Bump codecov/codecov-action from 3 to 4 by @dependabot in #1328
• Disable docker release on PR by @LennartPurucker in #1360
• fix(datasets): Add code 111 for dataset description not found error by @eddiebergman in #1356
• Test Fixes for v0.15.1 by @LennartPurucker in #1358
• fix: Avoid Random State and Other Test Bug by @LennartPurucker in #1362
• fix/maint: Make Docs Work Again and Stop Progress.rst Usage by @LennartPurucker in #1365
• doc: README Rework by @LennartPurucker in #1361
• doc: make all examples use names instead of IDs as reference. by @LennartPurucker in #1367
• fix: avoid stripping whitespaces for feature names by @LennartPurucker in #1368
• fix: workaround for git test workflow for Python 3.8 by @LennartPurucker in #1369
• add: test for dataset comparison and ignore fields by @LennartPurucker in #1370
• fix: github workflows and pytest issue by @LennartPurucker in #1373
• feat: support for loose init model from run by @LennartPurucker in #1371
• fix/maint: avoid exit code (which kills the docs building) by @LennartPurucker in #1374
• ux: Provide helpful link to documentation when error due to missing API token by @eddiebergman in #1364
• ci: Docker/build-push-action from 5 to 6 by @dependabot in #1357
• ci: Bumb peter-evans/dockerhub-description from 3 to 4 by @dependabot in #1326
• fix: resolve Sphinx style error by @LennartPurucker in #1375
• docs: fix borken links after openml.org rework by @LennartPurucker in #1376
• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #1380
• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #1381
• Mark test as production by @PGijsbers in #1384
• Patch release bump by @PGijsbers in #1389

Full Changelog: v0.15.0...v0.15.1

What's Changed

• ADD #1335: Improve MinIO support.
  • Add progress bar for downloading MinIO files. Enable it with setting show_progress to true on either openml.config or the configuration file.
  • When using download_all_files, files are only downloaded if they do not yet exist in the cache.
• FIX #1338: Read the configuration file without overwriting it.
• MAINT #1340: Add Numpy 2.0 support. Update tests to work with scikit-learn <= 1.5.
• ADD #1342: Add HTTP header to requests to indicate they are from openml-python.
• ADD #1345: task.get_dataset now takes the same parameters as openml.datasets.get_dataset to allow fine-grained control over file downloads.
• MAINT #1346: The ARFF file of a dataset is now only downloaded if parquet is not available.
• MAINT #1349: Removed usage of the disutils module, which allows for Py3.12 compatibility.
• MAINT #1351: Image archives are now automatically deleted after they have been downloaded and extracted.
• MAINT #1352, 1354: When fetching tasks and datasets, file download parameters now default to not downloading the file.
  Files will be downloaded only when a user tries to access properties which require them (e.g., dataset.qualities or dataset.get_data).

New Contributors

• @BrunoBelucci made their first contribution in #1338
• @knyazer made their first contribution in #1345

Full Changelog: v0.14.2...v0.15.0

This is a minor release to support several hotfixes and technical debt.

• MAINT #1280: Use the server-provided parquet_url instead of minio_url to determine the location of the parquet file.
• ADD #716: add documentation for remaining attributes of classes and functions.
• ADD #1261: more annotations for type hints.
• MAINT #1294: update tests to new tag specification.
• FIX #1314: Update fetching a bucket from MinIO.
• FIX #1315: Make class label retrieval more lenient.
• ADD #1316: add feature descriptions ontologies support.
• MAINT #1310/#1307: switch to ruff and resolve all mypy errors.

IMPORTANT: This release paves the way towards a breaking update of OpenML-Python. From version 0.15, functions that had the option to return a pandas DataFrame will return a pandas DataFrame by default. This version (0.14) emits a warning if you still use the old access functionality.

More concretely:

• In 0.15 we will drop the ability to return dictionaries in listing calls and only provide pandas DataFrames. To disable warnings in 0.14 you have to request a pandas DataFrame (using output_format="dataframe").
• In 0.15 we will drop the ability to return datasets as numpy arrays and only provide pandas DataFrames. To disable warnings in 0.14 you have to request a pandas DataFrame (using dataset_format="dataframe").

Furthermore, from version 0.15, OpenML-Python will no longer download datasets and dataset metadata by default. This version (0.14) emits a warning if you don't explicitly specify the desired behavior.

Please see the pull requests #1258 and #1260 for further information.

• ADD #1081: New flag that allows disabling downloading dataset features.
• ADD #1132: New flag that forces a redownload of cached data.
• FIX #1244: Fixes a rare bug where task listing could fail when the server returned invalid data.
• DOC #1229: Fixes a comment string for the main example.
• DOC #1241: Fixes a comment in an example.
• MAINT #1124: Improve naming of helper functions that govern the cache directories.
• MAINT #1223, #1250: Update tools used in pre-commit to the latest versions (black==23.30, mypy==1.3.0, flake8==6.0.0).
• MAINT #1253: Update the citation request to the JMLR paper.
• MAINT #1246: Add a warning that warns the user that checking for duplicate runs on the server cannot be done without an API key.

• ADD #1028: Add functions to delete runs, flows, datasets, and tasks (e.g., openml.datasets.delete_dataset).
• ADD #1144: Add locally computed results to the OpenMLRun object’s representation if the run was created locally and not downloaded from the server.
• ADD #1180: Improve the error message when the checksum of a downloaded dataset does not match the checksum provided by the API.
• ADD #1201: Make OpenMLTraceIteration a dataclass.
• DOC #1069: Add argument documentation for the OpenMLRun class.
• FIX #1197 #559 #1131: Fix the order of ground truth and predictions in the OpenMLRun object and in format_prediction.
• FIX #1198: Support numpy 1.24 and higher.
• FIX #1216: Allow unknown task types on the server. This is only relevant when new task types are added to the test server.
• MAINT #1155: Add dependabot github action to automatically update other github actions.
• MAINT #1199: Obtain pre-commit’s flake8 from github.com instead of gitlab.com.
• MAINT #1215: Support latest numpy version.
• MAINT #1218: Test Python3.6 on Ubuntu 20.04 instead of the latest Ubuntu (which is 22.04).
• MAINT #1221 #1212 #1206 #1211: Update github actions to the latest versions.

Version 0.13.0

• FIX #1030: pre-commit hooks now no longer should issue a warning.
• FIX #1058, #1100: Avoid NoneType error when printing task without class_labels attribute.
• FIX #1110: Make arguments to create_study and create_suite that are defined as optional by the OpenML XSD actually optional.
• FIX #1147: openml.flow.flow_exists no longer requires an API key.
• FIX #1184: Automatically resolve proxies when downloading from minio. Turn this off by setting environment variable no_proxy="*".
• MAIN #1088: Do CI for Windows on Github Actions instead of Appveyor.
• MAINT #1104: Fix outdated docstring for list_task.
• MAIN #1146: Update the pre-commit dependencies.
• ADD #1103: Add a predictions property to OpenMLRun for easy accessibility of prediction data.
• ADD #1188: EXPERIMENTAL. Allow downloading all files from a minio bucket with download_all_files=True for get_dataset.

Version 0.12.1

• ADD #895/#1038: Measure runtimes of scikit-learn runs also for models which are parallelized via the joblib.
• DOC #1050: Refer to the webpage instead of the XML file in the main example.
• DOC #1051: Document existing extensions to OpenML-Python besides the shipped scikit-learn extension.
• FIX #1035: Render class attributes and methods again.
• FIX #1042: Fixes a rare concurrency issue with OpenML-Python and joblib which caused the joblib worker pool to fail.
• FIX #1053: Fixes a bug which could prevent importing the package in a docker container.

0.11.1

• ADD #964: Validate ignore_attribute, default_target_attribute, row_id_attribute are set to attributes that exist on the dataset when calling create_dataset.
• ADD #979: Dataset features and qualities are now also cached in pickle format.
• ADD #982: Add helper functions for column transformers.
• ADD #989: run_model_on_task will now warn the user the the model passed has already been fitted.
• ADD #1009 : Give possibility to not download the dataset qualities. The cached version is used even so download attribute is false.
• ADD #1016: Add scikit-learn 0.24 support.
• ADD #1020: Add option to parallelize evaluation of tasks with joblib.
• ADD #1022: Allow minimum version of dependencies to be listed for a flow, use more accurate minimum versions for scikit-learn dependencies.
• ADD #1023: Add admin-only calls for adding topics to datasets.
• ADD #1029: Add support for fetching dataset from a minio server in parquet format.
• ADD #1031: Generally improve runtime measurements, add them for some previously unsupported flows (e.g. BaseSearchCV derived flows).
• DOC #973 : Change the task used in the welcome page example so it no longer fails using numerical dataset.
• MAINT #671: Improved the performance of check_datasets_active by only querying the given list of datasets in contrast to querying all datasets. Modified the corresponding unit test.
• MAINT #891: Changed the way that numerical features are stored. Numerical features that range from 0 to 255 are now stored as uint8, which reduces the storage space required as well as storing and loading times.
• MAINT #975, #988: Add CI through Github Actions.
• MAINT #977: Allow short and long scenarios for unit tests. Reduce the workload for some unit tests.
• MAINT #985, #1000: Improve unit test stability and output readability, and adds load balancing.
• MAINT #1018: Refactor data loading and storage. Data is now compressed on the first call to get_data.
• MAINT #1024: Remove flaky decorator for study unit test.
• FIX #883 #884 #906 #972: Various improvements to the caching system.
• FIX #980: Speed up check_datasets_active.
• FIX #984: Add a retry mechanism when the server encounters a database issue.
• FIX #1004: Fixed an issue that prevented installation on some systems (e.g. Ubuntu).
• FIX #1013: Fixes a bug where OpenMLRun.setup_string was not uploaded to the server, prepares for run_details being sent from the server.
• FIX #1021: Fixes an issue that could occur when running unit tests and openml-python was not in PATH.
• FIX #1037: Fixes a bug where a dataset could not be loaded if a categorical value had listed nan-like as a possible category.

• ADD #753: Allows uploading custom flows to OpenML via OpenML-Python.
• ADD #777: Allows running a flow on pandas dataframes (in addition to numpy arrays).
• ADD #888: Allow passing a task_id to run_model_on_task.
• ADD #894: Support caching of datasets using feather format as an option.
• ADD #929: Add edit_dataset and fork_dataset to allow editing and forking of uploaded datasets.
• ADD #866, #943: Add support for scikit-learn's passthrough and drop when uploading flows to OpenML.
• ADD #879: Add support for scikit-learn's MLP hyperparameter layer_sizes.
• ADD #894: Support caching of datasets using feather format as an option.
• ADD #945: PEP 561 compliance for distributing Type information.
• DOC #660: Remove nonexistent argument from docstring.
• DOC #901: The API reference now documents the config file and its options.
• DOC #912: API reference now shows create_task.
• DOC #954: Remove TODO text from documentation.
• DOC #960: document how to upload multiple ignore attributes.
• FIX #873: Fixes an issue which resulted in incorrect URLs when printing OpenML objects after switching the server.
• FIX #885: Logger no longer registered by default. Added utility functions to easily register logging to console and file.
• FIX #890: Correct the scaling of data in the SVM example.
• MAINT #371: list_evaluations default size changed from None to 10_000.
• MAINT #767: Source distribution installation is now unit-tested.
• MAINT #781: Add pre-commit and automated code formatting with black.
• MAINT #804: Rename arguments of list_evaluations to indicate they expect lists of ids.
• MAINT #836: OpenML supports only pandas version 1.0.0 or above.
• MAINT #865: OpenML no longer bundles test files in the source distribution.
• MAINT #881: Improve the error message for too-long URIs.
• MAINT #897: Dropping support for Python 3.5.
• MAINT #916: Adding support for Python 3.8.
• MAINT #920: Improve error messages for dataset upload.
• MAINT #921: Improve hangling of the OpenML server URL in the config file.
• MAINT #925: Improve error handling and error message when loading datasets.
• MAINT #928: Restructures the contributing documentation.
• MAINT #936: Adding support for scikit-learn 0.23.X.
• MAINT #945: Make OpenML-Python PEP562 compliant.
• MAINT #951: Converts TaskType class to a TaskType enum.

• ADD #857: Adds task type ID to list_runs
• DOC #862: Added license BSD 3-Clause to each of the source files.