aml_pipelines.md

Transfer Learning w/ AML Pipelines

file: pipelines_master.py runtime: ~1 minute

You can run the training script train.py locally to train your model.

However, let's figure out how to scale our solution such that whenever a new dataset is uploaded to blob store, a new anomaly detection service is automatically created for this dataset.

We create two AML pipelines to achieve this.

First, we create a master AML pipeline (pipeline_master.py). This pipeline monitors the Azure Blob Storage container for new data. Whenever new data is added, it checks whether this is from a new location for which we don't have a model yet. If that is the case, it creates a new AML pipeline for that dataset, by calling (pipeline_slave.py).

AML pipeline for training the model

The AML pipeline for training a model is defined in pipelines_slave.py.

It contains the following steps:

1. data_prep - scale and crop images so that their size matches the size of the input layer of our model.
2. train_prednet - train the model using hyperdrive
3. register_prednet - register the model in the AML workspace for later deployment
4. batch_scoring - perform batch scoring on the test data.
5. train_clf - the test data is labeled for whether a video frame contains anomalies. We use train a classifier that uses the errors of the neural network model to predict whether a video frame contains an anomaly.
6. register_clf - register the trained classifier in the AML model registry

AML pipeline for dynamic generation of new training pipelines

The AML pipeline for this is defined in pipelines_master.py.

This pipeline contains one step:

1. create_pipelines - to create and publish a new training pipeline

At the bottom of the file, you can see how we ensure that the master pipeline creates a new training pipeline whenever a new dataset is uploaded to our datastore.

We do this by attaching a Schedule to our pipeline, telling it to look for changes in the default blob store of our datastore.

datastore = ws.get_default_datastore()

schedule = Schedule.create(workspace=ws, name=pipeline_name + "_sch",
                           pipeline_id=published_pipeline.id, 
                           experiment_name='Schedule_Run',
                           datastore=datastore,
                           wait_for_provisioning=True,
                           description="Datastore scheduler for Pipeline" + pipeline_name
                           )

Next step

If this all makes sense, go ahead and run the script pipelines_master.py.

You should see the following:

• Compute targets are created in the AML workspace
• Creation of Pipeline prednet_master
• That pipeline should immediately start running

Note: The first time you run this, it will take a while, because AML will build a Docker container that contains all the necessary software dependencies, which are defined in the AzureML Environment prednet in pipelines_master.py.

Literature

See this blog post: breaking-the-wall-between-data-scientists-and-app-developers-with-azure-devops