Real-time Stream Processing for AI with Databricks

Question

Pulumi · Accepted Answer

Real-time stream processing is a critical aspect of AI applications that require immediate insights and responses, such as fraud detection, live recommendations, and monitoring tools. To set up a real-time stream processing system using Databricks on the cloud, you need a cluster to process the data streams, and potentially jobs to orchestrate processing tasks.

Databricks is a unified data analytics platform that is widely used for big data processing and machine learning tasks. It provides an interactive workspace that allows teams to collaborate on shared projects in various languages like Python, Scala, SQL, and R.

Here's what we are going to do:

1. **Set up a Databricks Cluster**: Clusters are the compute resource in Databricks, which can be used to run interactive analysis or automated jobs.
2. **Create a Job for Processing**: The Databricks Job is a way to define a batch or streaming workload that can be executed on a cluster.
3. **Stream Processing Libraries**: Depending on the specific processing tasks, you might need specific libraries or dependencies. These can be attached to clusters.
4. **Monitor and Manage Streams**: Depending on the integration, you might set up notebooks or workflows that help manage and monitor the stream processing.

### Prerequisites for using this program:

- Pulumi CLI installed and configured with the appropriate access tokens for your cloud provider.
- A cloud account (AWS, Azure, or Google Cloud Platform) properly set up.
- Databricks workspace deployed in your cloud environment.
- The `pulumi_databricks` package installed in your Python environment, as we're going to use the Databricks provider for Pulumi.

Assuming you have all the prerequisites set up, we will now write a Pulumi program that sets up a stream processing cluster and a job for processing in Databricks.

```python
import pulumi
import pulumi_databricks as databricks

# Provision a new databricks cluster
# We configure the cluster with the necessary node types and autoscaling options
# For real-time processing, it's important to have appropriate resources
# Details: https://www.pulumi.com/registry/packages/databricks/api-docs/cluster/
cluster = databricks.Cluster("ai-processing-cluster",
    autoscale=databricks.ClusterAutoscaleArgs(
        min_workers=1,
        max_workers=5,
    ),
    node_type_id="Standard_D3_v2", # Choose a node type appropriate for your workload
    spark_version="7.3.x-scala2.12", # Spark version should match with your processing needs
    spark_conf={ # Optional Spark configurations for tuning
        "spark.databricks.delta.preview.enabled": "true",
        "spark.sql.streaming.schemaInference": "true",
    },
    enable_elastic_disk=True,
    instance_pool_id="YourInstancePoolID", # Optional: link to an instance pool if you've set one up for better cluster management
)

# Define a job for real-time stream processing on the cluster
# A job can run notebooks, JARs, Python scripts, or docker containers
# and can be scheduled or run in response to events.
# Details: https://www.pulumi.com/registry/packages/databricks/api-docs/job/
job = databricks.Job("ai-stream-processing-job",
    existing_cluster_id=cluster.id,
    libraries=[ # Libraries and dependencies needed for stream processing
        databricks.JobLibraryArgs(
            jar="dbfs:/my-jars/my-stream-processor.jar",
        ),
    ],
    # Configure the task to use a notebook, jar, or python wheel.
    # For streaming jobs, you'd typically use a JAR or a Python script
    new_cluster=databricks.JobClusterArgs(
        spark_version=cluster.spark_version,
        node_type_id=cluster.node_type_id,
        num_workers=2, # Set the number of workers for the job
    ),
    notebook_task=databricks.JobNotebookTaskArgs(
        notebook_path="/Users/you@example.com/MyNotebooks/StreamProcessor", # Path to your Databricks notebook
    ),
)

# Export the cluster and job IDs
pulumi.export('cluster_id', cluster.id)
pulumi.export('job_id', job.id)
```

Here's what this program does:

- It provisions a new Databricks cluster with an autoscale configuration. Depending on your workload, you may need to adjust the `min_workers`, `max_workers`, and `node_type_id`. The `spark_version` is also set based on the requirements of the stream processing libraries you plan to use.

- A Databricks job is then defined, linked to the aforementioned cluster. This job can be used to execute notebooks that contain your stream processing logic. The path to the notebook is specified along with libraries containing any external dependencies your code may have. You can also run JARs, Python scripts, or even docker containers within a job.

- Finally, we export the IDs of the cluster and the job for later use, perhaps in your CI/CD system or for tracking within the Pulumi console.

Keep in mind that this is a starting point. In a real-world scenario, you'll need to carefully configure your cluster, jobs, libraries, and monitoring based on your workload requirements and the specifics of your Databricks environment.