1. API Gateway as a Proxy for ML Model Endpoints


    To create an API Gateway as a proxy for ML model endpoints, you'll need to follow these steps:

    1. Define the API Gateway to route incoming requests.
    2. Set up an integration between the API Gateway and the backend service hosting your ML model.
    3. Deploy the API Gateway so it's accessible to clients.

    Below is a Python program using Pulumi with the AWS provider to achieve this. The program outlines three main parts:

    • Defining the API Gateway (RestApi)
    • Creating a resource within the API Gateway
    • Configuring an integration to the ML model endpoint

    The backend ML model could be hosted on an EC2 instance, Lambda function, ECS service, or any other compute service. For the purposes of this example, we'll assume the ML model is accessible via an HTTP endpoint, such as one provided by Amazon SageMaker.

    import pulumi import pulumi_aws as aws # Create a new REST API on API Gateway. This will act as a proxy to the ML endpoint. rest_api = aws.apigateway.RestApi('MLProxyAPI', description='API Gateway to proxy requests to ML model endpoint.' ) # Create a resource (such as /predict) within our REST API. All requests to this path # will be forwarded to the ML model's HTTP endpoint. prediction_resource = aws.apigateway.Resource('PredictResource', rest_api=rest_api.id, parent_id=rest_api.root_resource_id, path_part='predict' # The URL path for invoking the ML model. ) # Create a method for the prediction resource. This specifies the HTTP method # clients can use, in this case, we're allowing POST requests. prediction_method = aws.apigateway.Method('PredictPOSTMethod', rest_api=rest_api.id, resource_id=prediction_resource.id, http_method='POST', authorization='NONE' # Specifies the type of authorization, here we're allowing open access. ) # Configure the integration to connect the prediction resource to the actual ML model endpoint. # You might use a SageMaker endpoint, an EC2 instance, or any HTTP endpoint serving the ML model. ml_model_endpoint = "http://your-ml-model-endpoint" # Replace with your actual ML model endpoint URL. prediction_integration = aws.apigateway.Integration('PredictIntegration', rest_api=rest_api.id, resource_id=prediction_resource.id, http_method=prediction_method.http_method, integration_http_method='POST', # The backend HTTP method expected by the ML model endpoint. type='HTTP_PROXY', # Type HTTP_PROXY for straightforward proxying. uri=ml_model_endpoint # The URI of the ML model endpoint. ) # Deploy the API to make it accessible. We'll create a stage named 'v1'. deployment = aws.apigateway.Deployment('MLProxyAPIDeployment', rest_api=rest_api.id, stage_name='v1' ) # If you'd like to secure the API with an API key and usage plan, uncomment the lines below. # api_key = aws.apigateway.ApiKey('APIKey', enabled=True) # plan = aws.apigateway.UsagePlan('APIUsagePlan', # api_stages=[{ # 'apiId': rest_api.id, # 'stage': deployment.stage_name, # }], # throttle={ # 'burstLimit': 10, # 'rateLimit': 2, # }, # quota={ # 'limit': 1000, # 'period': 'MONTH', # 'offset': 1, # } # ) # Export the URL of the deployed API so we know where to send requests. pulumi.export('api_url', deployment.invoke_url.apply(lambda url: url + 'v1/predict'))

    Here's what happens in the program:

    • We create a RestApi resource, which defines the overall API Gateway.
    • We then create a Resource within that API Gateway to specify a particular path (e.g., /predict), where clients can make requests.
    • A Method is attached to the Resource, defining which HTTP method(s) clients can use.
    • We set up an Integration, connecting the /predict path to the backend ML model's HTTP endpoint. We're using an HTTP proxy integration, whereby the API Gateway forwards requests directly to the configured uri without modification.
    • Optionally, you can enable API key usage to secure your API, with the relevant AWS resources commented out in the example.
    • The API is deployed to a stage (v1), making it accessible via a generated URL.

    Finally, we export the api_url so you can know where to send requests to invoke the ML model.

    Remember to replace ml_model_endpoint with the actual URL of your ML model endpoint. If your model is hosted on AWS SageMaker or ECS, you would use the invocation endpoint for the model or service.

    Once you apply the program using Pulumi, it will set up the infrastructure as defined and give you back an API URL which can then be used to send predictions to your ML model.