Introduction to SklearnModel

Overview:

The SklearnModel module in ADS provides different ways of serializing a trained sklearn model. This example demonstrates how to utilize the SklearnModel module to prepare model artifacts, deploys models into the model catalog, and deploys any unsupported model framework.

A model artifact includes the model, metadata about the model, input and output schema, and a script to load the model and make predictions. You can share model artifacts among data scientists, track for provenance, reproduce, and deploy.

Initialize

SklearnModel() initiates a sklearn model instance and accepts the following variables:

estimator: (Callable). Trained sklearn model or sklearn pipeline.
artifact_dir: str. Artifact directory to store the files needed for deployment.
properties: (ModelProperties, optional). Defaults to None. The ModelProperties object required to save and deploy a model.
auth :(dict, optional). Defaults to None. The default authentication is set using the ads.set_auth API. If you need to override the default, use ads.common.auth.api_keys or ads.common.auth.resource_principal to create appropriate authentication signer and kwargs required to instantiate IdentityClient object.

The score.py file is auto generated and not required to be modified. You can change its contents. For example, add your preferred steps to pre_inference and post_inference. the properties instance of ModelProperties and has the following predefined fields:

inference_conda_env: str
inference_python_version: str
training_conda_env: str
training_python_version: str
training_resource_id: str
training_script_path: str
training_id: str
compartment_id: str
project_id: str
deployment_instance_shape: str
deployment_instance_count: int
deployment_bandwidth_mbps: int
deployment_log_group_id: str
deployment_access_log_id: str
deployment_predict_log_id: str

By default, properties is populated from environment variables if it’s not specified. For example, in the notebook session the environment variables for such as project id, compartment id are preset and stored in PROJECT_OCID and NB_SESSION_COMPARTMENT_OCID by default. And properties populates those variables from the environment variables, and uses those values in the functions such as .save(), .deployment() by default. However, you can always explicitly pass those variables into the functions to overwrite the values. For the fields that properties has, it records the values that you pass into the functions. For example, when you pass in inference_conda_env into .prepare(), then properties records this value, and you can export it using .to_yaml(). And reload it using .from_yaml() from any machine. You can reuse the properties in different places.

Summary_status

You can call the .summary_status() function any time after the SklearnModel instance is created. It returns a Pandas dataframe that guides you though the entire workflow. It shows which function is available to call, which ones are not, and what each function is doing. If extra actions are required, it also shows those.

An example of summary status table is similar to the following after you initiate the model instance. The step column shows all the functions. It shows that initiate step is completed and the Details column explains that what initiate step did, and that prepare() now is available. The next step is to call prepare().

Prepare

.prepare() takes the following parameters:

inference_conda_env: (str, optional). Defaults to None. Can be either slug or the Object Storage path of the conda environment. You can only pass in slugs if the conda environment is a service environment.
inference_python_version: (str, optional). Defaults to None. Python version to use in deployment.
training_conda_env: (str, optional). Defaults to None. Can be either slug or the Object Storage path of the conda environment. You can only pass in slugs if the conda environment is a service environment.
training_python_version: (str, optional). Defaults to None. Python version used during training.
model_file_name: (str). Name of the serialized model.
as_onnx: (bool, optional). Defaults to False. Whether to serialize as ONNX model.
initial_types: (list[Tuple], optional). Defaults to None. Each element is a tuple of a variable name and a type, see sklearn API for more explanation and examples for initial_types.
force_overwrite: (bool, optional). Defaults to False. Whether to overwrite existing files.
namespace: (str, optional). Namespace of region. This is used for identifying which region the service environment is from when you pass a slug to inference_conda_env and training_conda_env.
use_case_type: str. The use case type of the model. Use it with the UserCaseType class or string provided in UseCaseType. For example, use_case_type=UseCaseType.BINARY_CLASSIFICATION or use_case_type="binary_classification", see the UseCaseType class for all supported types.
X_sample: Union[dict, str, list, np.ndarray, pd.core.series.Series, pd.core.frame.DataFrame]. Defaults to None.
y_sample: Union[dict, str, list, pd.Series, np.ndarray]. Defaults to None. A sample of output data that is used to generate output schema.
training_script_path: str. Defaults to None. Training script path.
training_id: (str, optional). Defaults to value from environment variables. The training OCID for model. Can be notebook session or job OCID.
ignore_pending_changes: bool. Defaults to False. Whether to ignore the pending changes in Git.
max_col_num: (int, optional). Defaults to utils.DATA_SCHEMA_MAX_COL_NUM. The maximum column size of the data that allows you to automatically generate schema.

kwargs:

impute_values: (dict, optional). The dictionary where the key is the column index (or names is accepted for Pandas dataframe), and the value is the impute value for the corresponding column.

Note:

We provide two ways of serializing the models: local method which is supported by Sklearn and onnx method. By default, local method is used and also it is recommended way of serialize the model.
.prepare() takes variables that skl2onnx.convert_sklearn does.

It automatically generates the following files.

runtime.yaml
score.py
model.json by default. If as_onnx=True the default file name should be model.onnx. However, you can set model file name yourself.
input_schema.json When X_sample is passed in and the schema is more than 32kb.
output_schema.json When y_sample is passed in and the schema is more than 32kb.
hyperparameters.json If extracted hyperparameters is more than 32kb.

Verify

The .verify() function takes one parameter:

data (Union[dict, str, list, np.ndarray, pd.core.series.Series, pd.core.frame.DataFrame]). Data used to test if deployment works in a local environment.

You use it to test if deployment work sin a local environment. Before saving and deploying the model, we recommended that you call this function to check if the load_model and predict functions in score.py work. It takes and returns the same data as the model deployment predict takes and returns.

In SklearnModel, data serialization is supported for dictionary, string, list, np.ndarray, pd.core.series.Series, pd.core.frame.DataFrame, which means that you can pass in Pandas dataframe or Numpy array even though they are not JSON serializable. This is because the data is automatically serializes and deserialized.

Save

The .save() function takes the following parameters:

display_name: (str, optional). Defaults to None. The name of the model.
description: (str, optional). Defaults to None. The description of the model.
freeform_tags : Dict(str, str). Defaults to None. Free form tags for the model.
defined_tags : (Dict(str, dict(str, object)), optional). Defaults to None. Defined tags for the model.
ignore_introspection: (bool, optional). Defaults to None. Determines whether to ignore the result of model introspection or not. If set to True, then save () ignores all model introspection errors.

kwargs:

project_id: (str, optional). Project OCID. If not specified, the value is taken either from the environment variables or model properties.
compartment_id : (str, optional). Compartment OCID. If not specified, the value is taken either from the environment variables or model properties.
timeout: (int, optional). Defaults to 10 seconds. The connection timeout in seconds for the client.

It first reloads the score.py and runtime.yaml files from disk so that any changes made to those files can be picked up. Then it conducts an introspection test by default. However, you can set ignore_introspection=False to avoid it. Introspection test checks if .deployment() could have some issues and suggests the necessary actions that you can use to fix then. Lastly, it uploads the artifacts to the model catalog, and returns a model_id for the saved model. You can also call .instrospect() to conduct the test any time after .prepare() is called.

Deploy

.deploy() takes the following parameters:

wait_for_completion : (bool, optional). Defaults to True. Flag set for whether to wait for deployment to complete before proceeding.
display_name: (str, optional). Defaults to None. The name of the model.
description: (str, optional). Defaults to None. The description of the model.
deployment_instance_shape: (str, optional). Defaults to VM.Standard2.1. The shape of the instance used for deployment.
deployment_instance_count: (int, optional). Defaults to 1. The number of instance used for deployment.
deployment_bandwidth_mbps: (int, optional). Defaults to 10. The bandwidth limit on the load balancer in Mbps.
deployment_log_group_id: (str, optional). Defaults to None. The OCI logging group id. The access log and predict log share the same log group.
deployment_access_log_id: (str, optional). Defaults to None. The access log OCID for the access logs, see logging.
deployment_predict_log_id: (str, optional). Defaults to None. The predict log OCID for the predict logs, see logging.

kwargs: - project_id: (str, optional). Project OCID. If not specified, the value is taken from the environment variables. - compartment_id : (str, optional). Compartment OCID. If not specified, the value is taken from the environment variables. - max_wait_time : (int, optional). Defaults to 1200 seconds. Maximum amount of time to wait in seconds. Negative implies infinite wait time. - poll_interval : (int, optional). Defaults to 60 seconds. Poll interval in seconds.

this function deploys the model. In order to make deployment more smooth, we suggest using exactly the same conda environments for both local development and deployment. Discrepancy between the two could cause problems.

You can pass in deployment_log_group_id, deployment_access_log_id and deployment_predict_log_id to enable the logging. Please refer to this logging example for an example on logging. To create a log group, you can reference Logging session.

Predict

The .predict() function takes one parameter, Data, expected by the predict API in score.py. - data (Union[dict, str, list, np.ndarray, pd.core.series.Series, pd.core.frame.DataFrame]).

.predict() takes the same data that .verify() takes, you must ensure that the data passed and returned by predict in the score.py is JSON serializable. It passes the data to the model deployment endpoint, and calls the predict function in the score.py.

Delete_deployment

The .delete_deployment() function takes one parameter:

wait_for_completion: (bool, optional). Defaults to False. Whether to wait until completion.

If you don’t need the deployment any more, you can call delete_deployment to delete the current deployment that is attached to this model. Each time you call deploy, it creates a new deployment and only the new deployment is attached to this model.

from_model_artifact

.from_model_artifact() allows to load a model from a folder, zip or tar achive files, where the folder/zip/tar files should contain the files such as runtime.yaml, score.py, the serialized model file needed for deployments. It takes the following parameters:

uri: str: The folder path, ZIP file path, or TAR file path. It could contain a seriliazed model(required) as well as any files needed for deployment including: serialized model, runtime.yaml, score.py and etc. The content of the folder will be copied to the artifact_dir folder.
model_file_name: str: The serialized model file name.
artifact_dir: str: The artifact directory to store the files needed for deployment.
auth: (Dict, optional): Defaults to None. The default authetication is set using ads.set_auth API. If you need to override the default, use the ads.common.auth.api_keys or ads.common.auth.resource_principal to create appropriate authentication signer and kwargs required to instantiate IdentityClient object.
force_overwrite: (bool, optional): Defaults to False. Whether to overwrite existing files or not.
properties: (ModelProperties, optional): Defaults to None. ModelProperties object required to save and deploy model.

After this is called, you can call .verify(), .save() and etc.

from_model_catalog

from_model_catalog allows to load a remote model from model catalog using a model id , which should contain the files such as runtime.yaml, score.py, the serialized model file needed for deployments. It takes the following parameters:

model_id: str. The model OCID.
model_file_name: (str). The name of the serialized model.
artifact_dir: str. The artifact directory to store the files needed for deployment. Will be created if not exists.
auth: (Dict, optional). Defaults to None. The default authetication is set using ads.set_auth API. If you need to override the default, use the ads.common.auth.api_keys or ads.common.auth.resource_principal to create appropriate authentication signer and kwargs required to instantiate IdentityClient object.
force_overwrite: (bool, optional). Defaults to False. Whether to overwrite existing files or not.
properties: (ModelProperties, optional). Defaults to None. ModelProperties object required to save and deploy model.

kwargs:

compartment_id : (str, optional). Compartment OCID. If not specified, the value will be taken from the environment variables.
timeout : (int, optional). Defaults to 10 seconds. The connection timeout in seconds for the client.

Examples

Create an sklearn pipeline

import pandas as pd
import numpy as np
import os

from sklearn.pipeline import Pipeline
from sklearn.compose import ColumnTransformer
from sklearn.ensemble import RandomForestClassifier
from sklearn.preprocessing import OrdinalEncoder, LabelEncoder
from sklearn.model_selection import train_test_split

ds_path = os.path.join("/", "opt", "notebooks", "ads-examples", "oracle_data", "orcl_attrition.csv")
df = pd.read_csv(ds_path)
y = df["Attrition"]
X = df.drop(columns=["Attrition"])

# Data Preprocessing
for i, col in X.iteritems():
    col.replace("unknown", "", inplace=True)
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.1, random_state=42)

# Label encode the y values
le = LabelEncoder()
y_train = le.fit_transform(y_train)
y_test = le.transform(y_test)

# Extract numerical columns and categorical columns
categorical_cols = []
numerical_cols = []
for i, col in X.iteritems():
    if col.dtypes == "object":
        categorical_cols.append(col.name)
    else:
        numerical_cols.append(col.name)

categorical_transformer = Pipeline(steps=[
    ('encoder', OrdinalEncoder(handle_unknown="use_encoded_value", unknown_value=-999))
])
preprocessor = ColumnTransformer(
    transformers=[
        ('cat', categorical_transformer, categorical_cols)
])

ml_model = RandomForestClassifier(n_estimators=100, random_state=0)
estimator = Pipeline(steps=[('preprocessor', preprocessor),
('model', ml_model)
])

estimator.fit(X_train, y_train)

Sklearn Framework Serialization

from ads.model.framework.sklearn_model import SklearnModel
import tempfile
model = SklearnModel(estimator=estimator, artifact_dir=tempfile.mkdtemp())

model.summary_status()
model.prepare(inference_conda_env="generalml_p37_cpu_v1",
        force_overwrite=True,
        as_onnx=False,
        )
model.verify(X_test.head(2))
model.save(timeout=300)
model.deploy()
model.predict(X_test.head(2))

Onnx Serialization

from ads.model.framework.sklearn_model import SklearnModel
import tempfile
model = SklearnModel(estimator=estimator, artifact_dir=tempfile.mkdtemp())

model.summary_status()
model.prepare(inference_conda_env="generalml_p37_cpu_v1",
        force_overwrite=True,
        as_onnx=True,
        X_sample=X_test.head(2),
        )
model.verify(X_test.head(2))
model.save(timeout=300)
model.deploy()
model.predict(X_test.head(2))

Loading Model From a Zip Archive

model = SklearnModel.from_model_artifact("/folder_to_your/artifact.zip",
                                      model_file_name="your_model_file_name",
                                      artifact_dir=tempfile.mkdtemp())
model.verify(your_data)

Loading Model From Model Catalog

model = SklearnModel.from_model_catalog(model_id="ocid1.datasciencemodel.oc1.iad.amaaaa....",
                                      model_file_name="your_model_file_name",
                                      artifact_dir=tempfile.mkdtemp())
model.verify(your_data)