Instant ML Model Endpoint Creation Using AWS Lambda Function URLs

Question

Pulumi · Accepted Answer

To create an instant machine learning (ML) model endpoint using AWS Lambda Function URLs, you will be taking advantage of several AWS services. AWS Lambda allows you to run code without provisioning or managing servers, and as of recent updates, it also allows you to create Function URLs, which are dedicated HTTP(S) endpoints for your Lambda functions. This is convenient for turning your Lambda function into a web-accessible API endpoint without needing to set up API Gateway.

In this scenario, we'll assume you have a pre-trained ML model that you can load into a Lambda function handler to make predictions. You'll use Pulumi's Infrastructure as Code (IaC) framework to codify this setup. The main resources you'll define are:

1. **AWS IAM Role:** An IAM role with permissions that AWS Lambda will assume when executing the function.
2. **AWS Lambda Function:** The actual Lambda function where you'll load and invoke your ML model.
3. **Lambda Function URL:** An HTTP(S) endpoint for your Lambda function, making it easily accessible over the web.

Here's a Pulumi program in Python that defines these resources:

```python
import pulumi
import pulumi_aws as aws

# IAM role for the Lambda function, granting necessary permissions
lambda_role = aws.iam.Role("lambdaRole",
    assume_role_policy="""{
        "Version": "2012-10-17",
        "Statement": [{
            "Action": "sts:AssumeRole",
            "Effect": "Allow",
            "Principal": {
                "Service": "lambda.amazonaws.com"
            }
        }]
    }"""
)

# Attaching the AWS managed LambdaExec role policy to the role created
lambda_policy_attachment = aws.iam.RolePolicyAttachment("lambdaPolicyAttachment",
    role=lambda_role.name,
    policy_arn="arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole",
)

# Creating the Lambda function
lambda_function = aws.lambda_.Function("mlModelLambdaFunction",
    code=pulumi.FileArchive("./lambda_package.zip"),
    role=lambda_role.arn,
    handler="handler.main",  # Assuming the main function in "handler.py" is the entry point
    runtime="python3.8",    # Specify the correct runtime for your model
)

# Creating the Function URL for the Lambda Function
function_url = aws.lambda_.FunctionUrl("mlModelFunctionUrl",
    function_name=lambda_function.name,
    authorization_type="NONE",  # Use IAM or AWS_IAM if you want to protect your endpoint
)

# Export the endpoint URL
pulumi.export("function_url", function_url.function_url)
```

Here's a breakdown of what each section of the code does:

- The `lambda_role` resource creates an IAM role that defines what the Lambda function is allowed to do. The assume_role_policy allows Lambda services to assume this role.
- The `lambda_policy_attachment` attaches the AWS managed policy for Lambda functions, which gives your function the necessary permissions to execute and create log streams.
- The `lambda_function` defines your actual Lambda function. It includes the source code as a zip file, the IAM role to use, the handler, which is the method in your source code that Lambda will call to start execution, and the runtime, which needs to match the programming language you used to write your Lambda function.
- The `function_url` creates a Function URL, enabling the invocation of the Lambda function over HTTPS. Setting `authorization_type` to `"NONE"` means that no authentication is required to call this endpoint, which you might want to change for production workloads.
- Lastly, the `pulumi.export` line outputs the Function URL once the Pulumi program has been applied. You can use this URL to interact with your ML model.

To use this Pulumi code:

1. Install Pulumi and configure AWS credentials.
2. Have your Lambda function code and ML model packaged in `lambda_package.zip`. The code should include a function called `main` (or adjust the handler in the code accordingly) that loads the ML model and performs a prediction based on the incoming event data from the Function URL.
3. Create a new Pulumi project and use this code as your `__main__.py`.
4. Run `pulumi up` to deploy your resources. The function URL will be printed upon successful deployment.

Remember that this is a simple example for educational purposes. For production workloads, you would need to protect your endpoint with authentication and possibly include a more complex IAM policy to grant the function additional permissions, depending on the requirements of your ML model and workload.