SpineGroup#
SpineGroup#
hsfs.feature_group.SpineGroup(
storage_connector=None,
query=None,
data_format=None,
path=None,
options={},
name=None,
version=None,
description=None,
primary_key=None,
featurestore_id=None,
featurestore_name=None,
created=None,
creator=None,
id=None,
features=None,
location=None,
statistics_config=None,
event_time=None,
expectation_suite=None,
online_enabled=False,
href=None,
online_topic_name=None,
topic_name=None,
spine=True,
dataframe="spine",
deprecated=False,
**kwargs
)
Creation#
get_or_create_spine_group#
FeatureStore.get_or_create_spine_group(
name, version=None, description="", primary_key=[], event_time=None, features=[], dataframe=None
)
Create a spine group metadata object.
Instead of using a feature group to save a label/prediction target, you can use a spine together with a dataframe containing the labels. A Spine is essentially a metadata object similar to a feature group, however, the data is not materialized in the feature store. It only containes the needed metadata such as the relevant event time column and primary key columns to perform point-in-time correct joins.
Example
# connect to the Feature Store
fs = ...
spine_df = pd.Dataframe()
spine_group = fs.get_or_create_spine_group(
name="sales",
version=1,
description="Physical shop sales features",
primary_key=['ss_store_sk'],
event_time='sale_date',
dataframe=spine_df
)
Note that you can inspect the dataframe in the spine group, or replace the dataframe:
spine_group.dataframe.show()
spine_group.dataframe = new_df
The spine can then be used to construct queries, with only one speciality:
Note
Spines can only be used on the left side of a feature join, as this is the base set of entities for which features are to be fetched and the left side of the join determines the event timestamps to compare against.
If you want to use the query for a feature view to be used for online serving, you can only select the label or target feature from the spine. For the online lookup, the label is not required, therefore it is important to only select label from the left feature group, so that we don't need to provide a spine for online serving.
These queries can then be used to create feature views. Since the dataframe contained in the spine is not being materialized, every time you use a feature view created with spine to read data you will have to provide a dataframe with the same structure again.
For example, to generate training data:
X_train, X_test, y_train, y_test = feature_view_spine.train_test_split(0.2, spine=training_data_entities)
Or to get batches of fresh data for batch scoring:
feature_view_spine.get_batch_data(spine=scoring_entities_df).show()
Here you have the chance to pass a different set of entities to generate the training dataset.
Sometimes it might be handy to create a feature view with a regular feature group containing the label, but then at serving time to use a spine in order to fetch features for example only for a small set of primary key values. To do this, you can pass the spine group instead of a dataframe. Just make sure it contains the needed primary key, event time and label column.
feature_view.get_batch_data(spine=spine_group)
Arguments
- name
str
: Name of the spine group to create. - version
Optional[int]
: Version of the spine group to retrieve, defaults toNone
and will create the spine group with incremented version from the last version in the feature store. - description
Optional[str]
: A string describing the contents of the spine group to improve discoverability for Data Scientists, defaults to empty string""
. - primary_key
Optional[List[str]]
: A list of feature names to be used as primary key for the spine group. This primary key can be a composite key of multiple features and will be used as joining key, if not specified otherwise. Defaults to empty list[]
, and the spine group won't have any primary key. - event_time
Optional[str]
: Optionally, provide the name of the feature containing the event time for the features in this spine group. If event_time is set the spine group can be used for point-in-time joins. Defaults toNone
. - features
Optional[List[hsfs.feature.Feature]]
: Optionally, define the schema of the spine group manually as a list ofFeature
objects. Defaults to empty list[]
and will use the schema information of the DataFrame resulting by executing the provided query against the data source.
Event time data type restriction
The supported data types for the event time column are: timestamp
, date
and bigint
.
- dataframe
Union[pandas.DataFrame, pyspark.sql.DataFrame, pyspark.RDD, numpy.ndarray, List[list]]
: DataFrame, RDD, Ndarray, list. Spine dataframe with primary key, event time and label column to use for point in time join when fetching features.
Returns
SpineGroup
. The spine group metadata object.
Retrieval#
get_or_create_spine_group#
FeatureStore.get_or_create_spine_group(
name, version=None, description="", primary_key=[], event_time=None, features=[], dataframe=None
)
Create a spine group metadata object.
Instead of using a feature group to save a label/prediction target, you can use a spine together with a dataframe containing the labels. A Spine is essentially a metadata object similar to a feature group, however, the data is not materialized in the feature store. It only containes the needed metadata such as the relevant event time column and primary key columns to perform point-in-time correct joins.
Example
# connect to the Feature Store
fs = ...
spine_df = pd.Dataframe()
spine_group = fs.get_or_create_spine_group(
name="sales",
version=1,
description="Physical shop sales features",
primary_key=['ss_store_sk'],
event_time='sale_date',
dataframe=spine_df
)
Note that you can inspect the dataframe in the spine group, or replace the dataframe:
spine_group.dataframe.show()
spine_group.dataframe = new_df
The spine can then be used to construct queries, with only one speciality:
Note
Spines can only be used on the left side of a feature join, as this is the base set of entities for which features are to be fetched and the left side of the join determines the event timestamps to compare against.
If you want to use the query for a feature view to be used for online serving, you can only select the label or target feature from the spine. For the online lookup, the label is not required, therefore it is important to only select label from the left feature group, so that we don't need to provide a spine for online serving.
These queries can then be used to create feature views. Since the dataframe contained in the spine is not being materialized, every time you use a feature view created with spine to read data you will have to provide a dataframe with the same structure again.
For example, to generate training data:
X_train, X_test, y_train, y_test = feature_view_spine.train_test_split(0.2, spine=training_data_entities)
Or to get batches of fresh data for batch scoring:
feature_view_spine.get_batch_data(spine=scoring_entities_df).show()
Here you have the chance to pass a different set of entities to generate the training dataset.
Sometimes it might be handy to create a feature view with a regular feature group containing the label, but then at serving time to use a spine in order to fetch features for example only for a small set of primary key values. To do this, you can pass the spine group instead of a dataframe. Just make sure it contains the needed primary key, event time and label column.
feature_view.get_batch_data(spine=spine_group)
Arguments
- name
str
: Name of the spine group to create. - version
Optional[int]
: Version of the spine group to retrieve, defaults toNone
and will create the spine group with incremented version from the last version in the feature store. - description
Optional[str]
: A string describing the contents of the spine group to improve discoverability for Data Scientists, defaults to empty string""
. - primary_key
Optional[List[str]]
: A list of feature names to be used as primary key for the spine group. This primary key can be a composite key of multiple features and will be used as joining key, if not specified otherwise. Defaults to empty list[]
, and the spine group won't have any primary key. - event_time
Optional[str]
: Optionally, provide the name of the feature containing the event time for the features in this spine group. If event_time is set the spine group can be used for point-in-time joins. Defaults toNone
. - features
Optional[List[hsfs.feature.Feature]]
: Optionally, define the schema of the spine group manually as a list ofFeature
objects. Defaults to empty list[]
and will use the schema information of the DataFrame resulting by executing the provided query against the data source.
Event time data type restriction
The supported data types for the event time column are: timestamp
, date
and bigint
.
- dataframe
Union[pandas.DataFrame, pyspark.sql.DataFrame, pyspark.RDD, numpy.ndarray, List[list]]
: DataFrame, RDD, Ndarray, list. Spine dataframe with primary key, event time and label column to use for point in time join when fetching features.
Returns
SpineGroup
. The spine group metadata object.
Properties#
avro_schema#
Avro schema representation of the feature group.
dataframe#
Spine dataframe with primary key, event time and label column to use for point in time join when fetching features.
deprecated#
Setting if the feature group is deprecated.
event_time#
Event time feature in the feature group.
feature_store#
feature_store_id#
features#
Schema information.
name#
Name of the feature group.
primary_key#
List of features building the primary key.
topic_name#
The topic used for feature group data ingestion.
version#
Version number of the feature group.
Methods#
add_tag#
SpineGroup.add_tag(name, value)
Attach a tag to a feature group.
A tag consists of a
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg.add_tag(name="example_tag", value="42")
Arguments
- name
str
: Name of the tag to be added. - value: Value of the tag to be added.
Raises
hsfs.client.exceptions.RestAPIError
in case the backend fails to add the tag.
check_deprecated#
SpineGroup.check_deprecated()
delete#
SpineGroup.delete()
Drop the entire feature group along with its feature data.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(
name='bitcoin_price',
version=1
)
# delete the feature group
fg.delete()
Potentially dangerous operation
This operation drops all metadata associated with this version of the feature group and all the feature data in offline and online storage associated with it.
Raises
hsfs.client.exceptions.RestAPIError
.
delete_tag#
SpineGroup.delete_tag(name)
Delete a tag attached to a feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg.delete_tag("example_tag")
Arguments
- name
str
: Name of the tag to be removed.
Raises
hsfs.client.exceptions.RestAPIError
in case the backend fails to delete the tag.
filter#
SpineGroup.filter(f)
Apply filter to the feature group.
Selects all features and returns the resulting Query
with the applied filter.
Example
from hsfs.feature import Feature
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg.filter(Feature("weekly_sales") > 1000)
If you are planning to join the filtered feature group later on with another feature group, make sure to select the filtered feature explicitly from the respective feature group:
Example
fg.filter(fg.feature1 == 1).show(10)
Composite filters require parenthesis:
Example
fg.filter((fg.feature1 == 1) | (fg.feature2 >= 2))
Arguments
- f
Union[hsfs.constructor.filter.Filter, hsfs.constructor.filter.Logic]
: Filter object.
Returns
Query
. The query object with the applied filter.
get_complex_features#
SpineGroup.get_complex_features()
Returns the names of all features with a complex data type in this feature group.
Example
complex_dtype_features = fg.get_complex_features()
get_feature#
SpineGroup.get_feature(name)
Retrieve a Feature
object from the schema of the feature group.
There are several ways to access features of a feature group:
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
# get Feature instanse
fg.feature1
fg["feature1"]
fg.get_feature("feature1")
Note
Attribute access to features works only for non-reserved names. For example
features named id
or name
will not be accessible via fg.name
, instead
this will return the name of the feature group itself. Fall back on using
the get_feature
method.
Arguments:
name: The name of the feature to retrieve
Returns:
Feature: The feature object
Raises
hsfs.client.exceptions.FeatureStoreException
.
get_fg_name#
SpineGroup.get_fg_name()
get_generated_feature_groups#
SpineGroup.get_generated_feature_groups()
Get the generated feature groups using this feature group, based on explicit provenance. These feature groups can be accessible or inaccessible. Explicit provenance does not track deleted generated feature group links, so deleted will always be empty. For inaccessible feature groups, only a minimal information is returned.
Returns
ProvenanceLinks
: Object containing the section of provenance graph requested.
Raises
hsfs.client.exceptions.RestAPIError
.
get_generated_feature_views#
SpineGroup.get_generated_feature_views()
Get the generated feature view using this feature group, based on explicit provenance. These feature views can be accessible or inaccessible. Explicit provenance does not track deleted generated feature view links, so deleted will always be empty. For inaccessible feature views, only a minimal information is returned.
Returns
ProvenanceLinks
: Object containing the section of provenance graph requested.
Raises
hsfs.client.exceptions.RestAPIError
.
get_parent_feature_groups#
SpineGroup.get_parent_feature_groups()
Get the parents of this feature group, based on explicit provenance. Parents are feature groups or external feature groups. These feature groups can be accessible, deleted or inaccessible. For deleted and inaccessible feature groups, only a minimal information is returned.
Returns
ProvenanceLinks
: Object containing the section of provenance graph requested.
Raises
hsfs.client.exceptions.RestAPIError
.
get_tag#
SpineGroup.get_tag(name)
Get the tags of a feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg_tag_value = fg.get_tag("example_tag")
Arguments
- name
str
: Name of the tag to get.
Returns
tag value
Raises
hsfs.client.exceptions.RestAPIError
in case the backend fails to retrieve the tag.
get_tags#
SpineGroup.get_tags()
Retrieves all tags attached to a feature group.
Returns
Dict[str, obj]
of tags.
Raises
hsfs.client.exceptions.RestAPIError
in case the backend fails to retrieve the tags.
json#
SpineGroup.json()
select#
SpineGroup.select(features=[])
Select a subset of features of the feature group and return a query object.
The query can be used to construct joins of feature groups or create a feature view with a subset of features of the feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
from hsfs.feature import Feature
fg = fs.create_feature_group(
"fg",
features=[
Feature("id", type="string"),
Feature("ts", type="bigint"),
Feature("f1", type="date"),
Feature("f2", type="double")
],
primary_key=["id"],
event_time="ts")
# construct query
query = fg.select(["id", "f1"])
query.features
# [Feature('id', ...), Feature('f1', ...)]
Arguments
- features
Optional[List[Union[str, hsfs.feature.Feature]]]
: A list ofFeature
objects or feature names as strings to be selected, defaults to [].
Returns
Query
: A query object with the selected features of the feature group.
select_all#
SpineGroup.select_all(include_primary_key=True, include_event_time=True)
Select all features in the feature group and return a query object.
The query can be used to construct joins of feature groups or create a feature view.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instances
fg1 = fs.get_or_create_feature_group(...)
fg2 = fs.get_or_create_feature_group(...)
# construct the query
query = fg1.select_all().join(fg2.select_all())
# show first 5 rows
query.show(5)
# select all features exclude primary key and event time
from hsfs.feature import Feature
fg = fs.create_feature_group(
"fg",
features=[
Feature("id", type="string"),
Feature("ts", type="bigint"),
Feature("f1", type="date"),
Feature("f2", type="double")
],
primary_key=["id"],
event_time="ts")
query = fg.select_all()
query.features
# [Feature('id', ...), Feature('ts', ...), Feature('f1', ...), Feature('f2', ...)]
query = fg.select_all(include_primary_key=False, include_event_time=False)
query.features
# [Feature('f1', ...), Feature('f2', ...)]
Arguments
- include_primary_key
Optional[bool]
: If True, include primary key of the feature group to the feature list. Defaults to True. - include_event_time
Optional[bool]
: If True, include event time of the feature group to the feature list. Defaults to True.
Returns
Query
. A query object with all features of the feature group.
select_except#
SpineGroup.select_except(features=[])
Select all features including primary key and event time feature
of the feature group except provided features
and return a query object.
The query can be used to construct joins of feature groups or create a feature view with a subset of features of the feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
from hsfs.feature import Feature
fg = fs.create_feature_group(
"fg",
features=[
Feature("id", type="string"),
Feature("ts", type="bigint"),
Feature("f1", type="date"),
Feature("f2", type="double")
],
primary_key=["id"],
event_time="ts")
# construct query
query = fg.select_except(["ts", "f1"])
query.features
# [Feature('id', ...), Feature('f1', ...)]
Arguments
- features
Optional[List[Union[str, hsfs.feature.Feature]]]
: A list ofFeature
objects or feature names as strings to be excluded from the selection. Defaults to [], selecting all features.
Returns
Query
: A query object with the selected features of the feature group.
to_dict#
SpineGroup.to_dict()
update_deprecated#
SpineGroup.update_deprecated(deprecate=True)
Deprecate the feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg.update_deprecated(deprecate=True)
Safe update
This method updates the feature group safely. In case of failure your local metadata object will be kept unchanged.
Arguments
- deprecate
bool
: Boolean value identifying if the feature group should be deprecated. Defaults to True.
Returns
FeatureGroup
. The updated feature group object.
update_description#
SpineGroup.update_description(description)
Update the description of the feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg.update_description(description="Much better description.")
Safe update
This method updates the feature group description safely. In case of failure your local metadata object will keep the old description.
Arguments
- description
str
: New description string.
Returns
FeatureGroup
. The updated feature group object.
update_feature_description#
SpineGroup.update_feature_description(feature_name, description)
Update the description of a single feature in this feature group.
Example
# connect to the Feature Store
fs = ...
# get the Feature Group instance
fg = fs.get_or_create_feature_group(...)
fg.update_feature_description(feature_name="min_temp",
description="Much better feature description.")
Safe update
This method updates the feature description safely. In case of failure your local metadata object will keep the old description.
Arguments
- feature_name
str
: Name of the feature to be updated. - description
str
: New description string.
Returns
FeatureGroup
. The updated feature group object.
update_features#
SpineGroup.update_features(features)
Update metadata of features in this feature group.
Currently it's only supported to update the description of a feature.
Unsafe update
Note that if you use an existing Feature
object of the schema in the
feature group metadata object, this might leave your metadata object in a
corrupted state if the update fails.
Arguments
- features
Union[hsfs.feature.Feature, List[hsfs.feature.Feature]]
:Feature
or list of features. A feature object or list thereof to be updated.
Returns
FeatureGroup
. The updated feature group object.