NOTICE

The upcoming release of Featuretools 1.0.0 contains several breaking changes. Users are encouraged to test this version prior to release by installing from GitHub:

pip install https://github.com/alteryx/featuretools/archive/woodwork-integration.zip

For details on migrating to the new version, refer to Transitioning to Featuretools Version 1.0. Please report any issues in the Featuretools GitHub repo or by messaging in Alteryx Open Source Slack.

Source code for featuretools.feature_base.features_serializer

import json

from featuretools.utils.s3_utils import (
    get_transport_params,
    use_smartopen_features
)
from featuretools.utils.wrangle import _is_s3, _is_url
from featuretools.version import __version__ as ft_version

SCHEMA_VERSION = "7.0.0"


def save_features(features, location=None, profile_name=None):
    """Saves the features list as JSON to a specified filepath/S3 path, writes to an open file, or
    returns the serialized features as a JSON string. If no file provided, returns a string.

    Args:
        features (list[:class:`.FeatureBase`]): List of Feature definitions.

        location (str or :class:`.FileObject`, optional): The location of where to save
            the features list which must include the name of the file,
            or a writeable file handle to write to. If location is None, will return a JSON string
            of the serialized features.
            Default: None

        profile_name (str, bool): The AWS profile specified to write to S3. Will default to None and search for AWS credentials.
                                    Set to False to use an anonymous profile.

    Note:
        Features saved in one version of Featuretools are not guaranteed to work in another.
        After upgrading Featuretools, features may need to be generated again.

    Example:
        .. ipython:: python
            :suppress:

            from featuretools.tests.testing_utils import (
                make_ecommerce_entityset)
            import featuretools as ft
            es = make_ecommerce_entityset()
            import os

        .. code-block:: python

            f1 = ft.Feature(es["log"].ww["product_id"])
            f2 = ft.Feature(es["log"].ww["purchased"])
            f3 = ft.Feature(es["log"].ww["value"])

            features = [f1, f2, f3]

            filepath = os.path.join('/Home/features/', 'list.json')
            ft.save_features(features, filepath)

            f = open(filepath, 'w')
            ft.save_features(features, f)

            features_str = ft.save_features(features)
    .. seealso::
        :func:`.load_features`
    """
    return FeaturesSerializer(features).save(location, profile_name=profile_name)


class FeaturesSerializer(object):
    def __init__(self, feature_list):
        self.feature_list = feature_list
        self._features_dict = None

    def to_dict(self):
        names_list = [feat.unique_name() for feat in self.feature_list]
        es = self.feature_list[0].entityset

        return {
            'schema_version': SCHEMA_VERSION,
            'ft_version': ft_version,
            'entityset': es.to_dictionary(),
            'feature_list': names_list,
            'feature_definitions': self._feature_definitions(),
        }

    def save(self, location, profile_name):
        features_dict = self.to_dict()
        if location is None:
            return json.dumps(features_dict)
        if isinstance(location, str):
            if _is_url(location):
                raise ValueError("Writing to URLs is not supported")
            if _is_s3(location):
                transport_params = get_transport_params(profile_name)
                use_smartopen_features(location, features_dict, transport_params, read=False)
            else:
                with open(location, "w") as f:
                    json.dump(features_dict, f)
        else:
            json.dump(features_dict, location)

    def _feature_definitions(self):
        if not self._features_dict:
            self._features_dict = {}

            for feature in self.feature_list:
                self._serialize_feature(feature)

        return self._features_dict

    def _serialize_feature(self, feature):
        name = feature.unique_name()

        if name not in self._features_dict:
            self._features_dict[feature.unique_name()] = feature.to_dictionary()

            for dependency in feature.get_dependencies(deep=True):
                name = dependency.unique_name()
                if name not in self._features_dict:
                    self._features_dict[name] = dependency.to_dictionary()