Part 3: Serving#

In this part you use MLRun’s serving runtime to deploy the trained models from the previous stage a Voting Ensemble using max vote logic.
You will also use MLRun’s Feature store to receive the latest tag of the online Feature Vector we defined in the previous stage.

By the end of this tutorial you’ll learn how to:

  • Define a model class to load the models, run preprocessing, and predict on the data

  • Define Voting Ensemble function on top of our models

  • Test the serving function locally using the mock server

  • Deploy the function to the cluster and test it live

Environment setup#

First, make sure SciKit-Learn is installed in the correct version:

!pip install -U scikit-learn==1.0.2

Restart your kernel post installing. Secondly, since the work is done in this project scope, define the project itself for all your MLRun work in this notebook.

project_name = 'fraud-demo'
import mlrun

# Initialize the MLRun project object
project = mlrun.get_or_create_project(project_name, context="./", user_project=True)
> 2021-10-28 11:59:01,033 [info] loaded project fraud-demo from MLRun DB

Define model class#

  • Load models

  • Predict from the FS Online service via the source key

# mlrun: start-code
import numpy as np
from cloudpickle import load
from mlrun.serving.v2_serving import V2ModelServer

class ClassifierModel(V2ModelServer):
    def load(self):
        """load and initialize the model and/or other elements"""
        model_file, extra_data = self.get_model('.pkl')
        self.model = load(open(model_file, 'rb'))
    def predict(self, body: dict) -> list:
        """Generate model predictions from sample"""
        print(f"Input -> {body['inputs']}")
        feats = np.asarray(body['inputs'])
        result: np.ndarray = self.model.predict(feats)
        return result.tolist()
# mlrun: end-code

Define a serving function#

MLRun serving can produce managed real-time serverless pipelines from various tasks, including MLRun models or standard model files. The pipelines use the Nuclio real-time serverless engine, which can be deployed anywhere. Nuclio is a high-performance open-source serverless framework that’s focused on data, I/O, and compute-intensive workloads.

The EnrichmentVotingEnsemble and the EnrichmentModelRouter router classes auto enrich the request with data from the feature store. The router input accepts lists of inference request (each request can be a dict or list of incoming features/keys). It enriches the request with data from the specified feature vector (feature_vector_uri).

In many cases the features can have null values (None, NaN, Inf, …). The Enrichment routers can substitute the null value with fixed or statistical value per feature. This is done through the impute_policy parameter, which accepts the impute policy per feature (where * is used to specify the default). The value can be a fixed number for constants or $mean, $max, $min, $std, $count for statistical values. to substitute the value with the equivalent feature stats (taken from the feature store).

The code below performs the following steps:

  • Gather ClassifierModel code from this notebook

  • Define EnrichmentVotingEnsemble - Max-Vote based ensemble with feature enrichment and imputing

  • Add the previously trained models to the ensemble

# Create the serving function from the code above
serving_fn = mlrun.code_to_function('transaction-fraud', kind='serving', image="mlrun/mlrun")

serving_fn.set_topology('router', 'mlrun.serving.routers.EnrichmentVotingEnsemble', name='VotingEnsemble',
                        feature_vector_uri="transactions-fraud-short", impute_policy={"*": "$mean"})

model_names = [

for i, name in enumerate(model_names, start=1):
    serving_fn.add_model(name, class_name="ClassifierModel", model_path=project.get_artifact_uri(f"training_model#{i}:latest"))

# Plot the ensemble configuration

Test the server locally#

Before deploying the serving function, test it in the current notebook and check the model output.

# Create a mock server from the serving function
local_server = serving_fn.to_mock_server()
> 2021-10-28 11:59:11,260 [info] model RandomForestClassifier was loaded
> 2021-10-28 11:59:11,306 [info] model GradientBoostingClassifier was loaded
> 2021-10-28 11:59:11,350 [info] model AdaBoostClassifier was loaded
# Choose an id for the test
sample_id = 'C76780537'

model_inference_path = '/v2/models/infer'

# Send our sample ID for prediction
            body={'inputs': [[sample_id]]})

# Notice the input vector is printed 3 times (once per child model) and is enriched with data from the feature store
Input -> [[14.68, 14.68, 1.0, 14.68, 70.81]]
Input -> [[14.68, 14.68, 1.0, 14.68, 70.81]]
Input -> [[14.68, 14.68, 1.0, 14.68, 70.81]]
{'id': '757c736c985a4c42b3ebd58f3c50f1b2',
 'model_name': 'VotingEnsemble',
 'outputs': [0],
 'model_version': 'v1'}

Accessing the real-time feature vector directly#

You can also directly query the feature store values using the get_online_feature_service method. This method is used internally in the EnrichmentVotingEnsemble router class

import mlrun.feature_store as fstore

# Create the online feature service
svc = fstore.get_online_feature_service('transactions-fraud-short:latest', impute_policy={"*": "$mean"})

# Get sample feature vector
sample_fv = svc.get([{'source': sample_id}])
[{'amount_max_2h': 14.68,
  'amount_max_12h': 70.81,
  'amount_sum_2h': 14.68,
  'amount_count_2h': 1.0,
  'amount_avg_2h': 14.68}]

Deploying the function on the kubernetes cluster#

You can now deploy the function. Once it’s deployed you get a function with an http trigger that can be called from other locations.

import os

# Enable model monitoring

# Deploy the serving function
> 2021-10-28 11:59:17,554 [info] Starting remote function deploy
2021-10-28 11:59:17  (info) Deploying function
2021-10-28 11:59:17  (info) Building
2021-10-28 11:59:17  (info) Staging files and preparing base images
2021-10-28 11:59:17  (info) Building processor image
2021-10-28 11:59:19  (info) Build complete
2021-10-28 11:59:25  (info) Function deploy complete
> 2021-10-28 11:59:25,657 [info] successfully deployed function: {'internal_invocation_urls': ['nuclio-fraud-demo-admin-transaction-fraud.default-tenant.svc.cluster.local:8080'], 'external_invocation_urls': ['']}

Test the server#

Test the serving function and examine the model output.

# Choose an id for the test
sample_id = 'C76780537'

model_inference_path = '/v2/models/infer'

# Send the sample ID for prediction
                  body={'inputs': [[sample_id]]})
> 2021-10-28 11:59:25,722 [info] invoking function: {'method': 'POST', 'path': 'http://nuclio-fraud-demo-admin-transaction-fraud.default-tenant.svc.cluster.local:8080/v2/models/infer'}
{'id': '4b9c4914-964f-4bd5-903d-c4885ed7c090',
 'model_name': 'VotingEnsemble',
 'outputs': [0],
 'model_version': 'v1'}

You can also directly query the feature store values, which are used in the enrichment.

Simulate incoming data#

# Load the dataset
data = mlrun.get_dataitem('').as_df()

# Sample 50k lines
data = data.sample(50000)

# keys
sample_ids = data['source'].to_list()
from random import choice, uniform
from time import sleep

# Sending random requests
for _ in range(4000):
    data_point = choice(sample_ids)
        resp = serving_fn.invoke(path=model_inference_path, body={'inputs': [[data_point]]})
        sleep(uniform(0.2, 1.7))
    except OSError:
> 2021-10-28 12:00:23,079 [info] invoking function: {'method': 'POST', 'path': 'http://nuclio-fraud-demo-admin-transaction-fraud.default-tenant.svc.cluster.local:8080/v2/models/infer'}
{'id': '6b813638-e9ef-4e92-85c8-cfbd0b74fe32', 'model_name': 'VotingEnsemble', 'outputs': [0], 'model_version': 'v1'}
> 2021-10-28 12:00:23,857 [info] invoking function: {'method': 'POST', 'path': 'http://nuclio-fraud-demo-admin-transaction-fraud.default-tenant.svc.cluster.local:8080/v2/models/infer'}
{'id': 'f84bf2ec-a718-4e90-a7d5-fe08e254f3c8', 'model_name': 'VotingEnsemble', 'outputs': [0], 'model_version': 'v1'}
> 2021-10-28 12:00:24,545 [info] invoking function: {'method': 'POST', 'path': 'http://nuclio-fraud-demo-admin-transaction-fraud.default-tenant.svc.cluster.local:8080/v2/models/infer'}
{'id': '7bb023f7-edbc-47a6-937b-4a15c8380b74', 'model_name': 'VotingEnsemble', 'outputs': [0], 'model_version': 'v1'}
> 2021-10-28 12:00:24,921 [info] invoking function: {'method': 'POST', 'path': 'http://nuclio-fraud-demo-admin-transaction-fraud.default-tenant.svc.cluster.local:8080/v2/models/infer'}
{'id': '57882cca-537a-43e1-9986-1bbc72fb84b7', 'model_name': 'VotingEnsemble', 'outputs': [0], 'model_version': 'v1'}