FEAT CLI conversion

docs/changes.rst

@@ -9,6 +9,12 @@ skops Changelog
     :depth: 1
     :local:
 
+v0.5
+----
+- Added CLI entrypoint support (:func:`.cli.entrypoint.main_cli`)
+  and a command line function to convert Pickle files
+  to Skops files (:func:`.cli._convert.main`). :pr:`249` by `Erin Aho`_
+
 v0.4
 ----
 - :func:`.io.dump` and :func:`.io.load` now work with file like objects,
@@ -83,4 +89,5 @@ Contributors
 
 :user:`Adrin Jalali <adrinjalali>`, :user:`Merve Noyan <merveenoyan>`,
 :user:`Benjamin Bossan <BenjaminBossan>`, :user:`Ayyuce Demirbas
-<ayyucedemirbas>`, :user:`Prajjwal Mishra <p-mishra1>`
+<ayyucedemirbas>`, :user:`Prajjwal Mishra <p-mishra1>`,
+:user:`Erin Aho <E-Aho>`,

docs/persistence.rst

@@ -110,6 +110,22 @@ you have custom functions (say, a custom function to be used with
 most ``numpy`` and ``scipy`` functions should work. Therefore, you can save
 objects having references to functions such as ``numpy.sqrt``.
 
+Command Line Interface
+########
+Skops has a command line interface to convert SciKit-Learn models persisted with
+``Pickle`` to ``Skops`` files.
+
+To convert a file from the command line, use the ``skops convert`` entrypoint.
+
+Below is an example call to convert a file ``my_model.pkl`` to ``new_model.skops``:
+
+.. code:: console
+    skops convert my_model.pkl
+
+Further help for the different supported options can be found by calling
+``skops convert --help`` in a terminal.
+
+
 Supported libraries
 -------------------
 

setup.py

@@ -34,6 +34,14 @@
 
 
 def setup_package():
+    package_data = dict(
+        entry_points={
+            "console_scripts": [
+                "skops = skops.cli.entrypoint:main_cli",
+            ],
+        }
+    )
+
     metadata = dict(
         name=DISTNAME,
         maintainer=MAINTAINER,
@@ -72,7 +80,7 @@ def setup_package():
         include_package_data=True,
     )
 
-    setup(**metadata)
+    setup(**package_data, **metadata)
 
 
 if __name__ == "__main__":

skops/cli/_convert.py

@@ -0,0 +1,109 @@
+from __future__ import annotations
+
+import argparse
+import logging
+import os
+import pathlib
+import pickle
+from typing import Optional
+
+from skops.cli._utils import get_log_level
+from skops.io import dumps, get_untrusted_types
+
+
+def _convert_file(input_file: os.PathLike, output_file: os.PathLike):
+    """
+    Function that is called by ``skops convert`` entrypoint.
+
+    Loads a pickle model from the input path, converts to skops format, and saves to
+    output file.
+
+    Parameters
+    ----------
+    input_file : os.PathLike
+        Path of input .pkl model to load.
+
+    output_file : os.PathLike
+        Path to save .skops model to.
+
+    """
+    model_name = pathlib.Path(input_file).stem
+
+    logging.debug(f"Converting {model_name}")
+
+    with open(input_file, "rb") as f:
+        obj = pickle.load(f)
+    skops_dump = dumps(obj)
+
+    untrusted_types = get_untrusted_types(data=skops_dump)
+
+    if not untrusted_types:
+        logging.info(f"No unknown types found in {model_name}.")
+    else:
+        untrusted_str = ", ".join(untrusted_types)
+
+        logging.warning(
+            "Unknown Types Detected! "
+            f"While converting {model_name}, "
+            "the following unknown types were found: "
+            f"{untrusted_str}. "
+            f"When loading {output_file}, add 'trusted=True' to the skops.load call. "
+        )
+
+    with open(output_file, "wb") as out_file:
+        logging.debug(f"Writing to {output_file}")
+        out_file.write(skops_dump)
+
+
+def format_parser(
+    parser: Optional[argparse.ArgumentParser] = None,
+) -> argparse.ArgumentParser:
+    """Adds arguments and help to parent CLI parser for the convert method."""
+
+    if not parser:  # used in tests
+        parser = argparse.ArgumentParser()
+
+    parser_subgroup = parser.add_argument_group("convert")
+    parser_subgroup.add_argument("input", help="Path to an input file to convert. ")
+
+    parser_subgroup.add_argument(
+        "-o",
+        "--output-file",
+        help=(
+            "Specify the output file name for the converted skops file. "
+            "If not provided, will default to using the same name as the input file, "
+            "and saving to the current working directory with the suffix '.skops'."
+        ),
+        default=None,
+    )
+    parser_subgroup.add_argument(
+        "-v",
+        "--verbose",
+        help=(
+            "Increases verbosity of logging. Can be used multiple times to increase "
+            "verbosity further."
+        ),
+        action="count",
+        dest="loglevel",
+        default=0,
+    )
+    return parser
+
+
+def main(
+    parsed_args: argparse.Namespace,
+):
+    output_file = parsed_args.output_file
+    input_file = parsed_args.input
+
+    logging.basicConfig(format="%(message)s", level=get_log_level(parsed_args.loglevel))
+
+    if not output_file:
+        # No filename provided, defaulting to base file path
+        file_name = pathlib.Path(input_file).stem
+        output_file = pathlib.Path.cwd() / f"{file_name}.skops"
+
+    _convert_file(
+        input_file=input_file,
+        output_file=output_file,
+    )

skops/cli/_utils.py

@@ -0,0 +1,15 @@
+import logging
+
+
+def get_log_level(level: int = 0):
+    """Takes in verbosity from a CLI entrypoint (number of times -v specified),
+    and sets the logger to the required log level"""
+
+    all_levels = [logging.WARNING, logging.INFO, logging.DEBUG]
+
+    if level > len(all_levels):
+        level = len(all_levels)
+    elif level < 0:
+        level = 0
+
+    return all_levels[level]

skops/cli/entrypoint.py

@@ -0,0 +1,44 @@
+import argparse
+
+import skops.cli._convert
+
+
+def main_cli(command_line_args=None):
+    """
+    Main command line interface entrypoint for all command line Skops methods.
+
+    To add a new entrypoint:
+        1. Create a new method to call that accepts a namespace
+        2. Create a new subparser formatter to define the expected CL arguments
+        3. Add those to the function map.
+    """
+    entry_parser = argparse.ArgumentParser(
+        prog="Skops",
+        description="Main entrypoint for all command line Skops methods.",
+        add_help=True,
+    )
+
+    subparsers = entry_parser.add_subparsers(
+        title="Commands",
+        description="Skops command to call",
+        dest="cmd",
+        help="Sub-commands help",
+    )
+
+    # function_map should map a command to
+    #   method: the command to call
+    #   format_parser: the function used to create a subparser for that command
+    function_map = {
+        "convert": {
+            "method": skops.cli._convert.main,
+            "format_parser": skops.cli._convert.format_parser,
+        },
+    }
+
+    for func_name, values in function_map.items():
+        subparser = subparsers.add_parser(func_name)
+        subparser.set_defaults(func=values["method"])
+        values["format_parser"](subparser)
+
+    args = entry_parser.parse_args(command_line_args)
+    args.func(args)

skops/cli/tests/test_convert.py

@@ -0,0 +1,138 @@
+import logging
+import pathlib
+import pickle as pkl
+from unittest import mock
+
+import numpy as np
+import pytest
+
+from skops.cli import _convert
+from skops.io import load
+
+
+class MockUnsafeType:
+    def __init__(self):
+        pass
+
+
+class TestConvert:
+    model_name = "some_model_name"
+
+    @pytest.fixture
+    def safe_obj(self):
+        return np.ndarray([1, 2, 3, 4])
+
+    @pytest.fixture
+    def unsafe_obj(self):
+        return MockUnsafeType()
+
+    @pytest.fixture
+    def pkl_path(self, tmp_path):
+        return tmp_path / f"{self.model_name}.pkl"
+
+    @pytest.fixture
+    def skops_path(self, tmp_path):
+        return tmp_path / f"{self.model_name}.skops"
+
+    @pytest.fixture
+    def write_safe_file(self, pkl_path, safe_obj):
+        with open(pkl_path, "wb") as f:
+            pkl.dump(safe_obj, f)
+
+    @pytest.fixture
+    def write_unsafe_file(self, pkl_path, unsafe_obj):
+        with open(pkl_path, "wb") as f:
+            pkl.dump(unsafe_obj, f)
+
+    def test_base_case_works_as_expected(
+        self, pkl_path, tmp_path, skops_path, write_safe_file, safe_obj, caplog
+    ):
+        _convert._convert_file(pkl_path, skops_path)
+        persisted_obj = load(skops_path)
+        assert np.array_equal(persisted_obj, safe_obj)
+        assert MockUnsafeType.__name__ not in caplog.text
+
+    def test_unsafe_case_works_as_expected(
+        self, pkl_path, tmp_path, skops_path, write_unsafe_file, caplog
+    ):
+        caplog.set_level(logging.WARNING)
+        _convert._convert_file(pkl_path, skops_path)
+        persisted_obj = load(skops_path, trusted=True)
+
+        assert isinstance(persisted_obj, MockUnsafeType)
+
+        # check logging has warned that an unsafe type was found
+        assert MockUnsafeType.__name__ in caplog.text
+
+
+class TestMain:
+    @staticmethod
+    def assert_called_correctly(
+        mock_convert: mock.MagicMock,
+        path,
+        output_file=None,
+    ):
+        if not output_file:
+            output_file = pathlib.Path.cwd() / f"{pathlib.Path(path).stem}.skops"
+        mock_convert.assert_called_once_with(input_file=path, output_file=output_file)
+
+    @mock.patch("skops.cli._convert._convert_file")
+    def test_base_works_as_expected(self, mock_convert: mock.MagicMock):
+        path = "123.pkl"
+        namespace, _ = _convert.format_parser().parse_known_args([path])
+
+        _convert.main(namespace)
+        self.assert_called_correctly(mock_convert, path)
+
+    @mock.patch("skops.cli._convert._convert_file")
+    @pytest.mark.parametrize(
+        "input_path, output_file, expected_path",
+        [
+            ("abc.123", "a/b/c", "a/b/c"),
+            ("abc.123", None, pathlib.Path.cwd() / "abc.skops"),
+        ],
+        ids=["Given an output path", "No output path"],
+    )
+    def test_with_output_dir_works_as_expected(
+        self, mock_convert: mock.MagicMock, input_path, output_file, expected_path
+    ):
+        if output_file is not None:
+            args = [input_path, "--output", output_file]
+        else:
+            args = [input_path]
+
+        namespace, _ = _convert.format_parser().parse_known_args(args)
+
+        _convert.main(namespace)
+        self.assert_called_correctly(
+            mock_convert, path=input_path, output_file=expected_path
+        )
+
+    @mock.patch("skops.cli._convert._convert_file")
+    @pytest.mark.parametrize(
+        "verbosity, expected_level",
+        [
+            ("", logging.WARNING),
+            ("-v", logging.INFO),
+            ("--verbose", logging.INFO),
+            ("-vv", logging.DEBUG),
+            ("-v -v", logging.DEBUG),
+            ("-vvv", logging.DEBUG),
+            ("--verbose --verbose", logging.DEBUG),
+        ],
+    )
+    def test_given_log_levels_works_as_expected(
+        self, mock_convert: mock.MagicMock, verbosity, expected_level, caplog
+    ):
+        input_path = "abc.def"
+        output_path = "bde.skops"
+        args = [input_path, "--output", output_path, verbosity.split()]
+
+        namespace, _ = _convert.format_parser().parse_known_args(args)
+
+        _convert.main(namespace)
+        self.assert_called_correctly(
+            mock_convert, path=input_path, output_file=output_path
+        )
+
+        assert caplog.at_level(expected_level)