1. Secure AI API Gateway on Azure Application Gateway


    To create a secure AI API Gateway using Azure Application Gateway, we will need to configure a number of resources with Pulumi. The Azure Application Gateway acts as a web traffic load balancer that enables you to manage traffic to your web applications. A typical setup includes specifics for routing rules, backend pools, listeners for different protocols, and potentially a Web Application Firewall (WAF) for security purposes.

    Below is a high-level overview of the resources we'll define in our Pulumi program:

    1. Application Gateway: This is the main resource that provides the Application Gateway service. We will configure this resource with all the necessary settings such as SKU, listeners, backend pools, and HTTP settings. It also has the capability to associate with a WAF policy for enhanced security.

    2. Web Application Firewall Policy: This optional resource provides rules to protect the Application Gateway from common web vulnerabilities and attacks. It can be attached to the Application Gateway resource.

    Now, let's write a Pulumi program in Python that will set up an Application Gateway with a basic configuration. If needed, you can further enhance this configuration with additional properties like SSL termination, URL path-based routing, and integration with Azure's Web Application Firewall for security hardening.

    Let's start by creating the Application Gateway with minimal configurations for demonstration purposes. Additionally, for a more secure and production-ready environment, you would configure SSL, more complex routing rules, backend pools, and other security measures such as a WAF policy.

    Here's the Pulumi program in Python:

    import pulumi import pulumi_azure_native as azure_native # This creates a new resource group for the Application Gateway. resource_group = azure_native.resources.ResourceGroup("resourceGroup") # Create a public IP for the Application Gateway (This step is optional if you have an existing one) public_ip = azure_native.network.PublicIPAddress( "publicIp", resource_group_name=resource_group.name, location=resource_group.location, public_ip_allocation_method=azure_native.network.IPAllocationMethod.STATIC, ) # Create the Application Gateway app_gateway = azure_native.network.ApplicationGateway( "appGateway", resource_group_name=resource_group.name, location=resource_group.location, sku=azure_native.network.ApplicationGatewaySkuArgs( name=azure_native.network.ApplicationGatewaySkuName.STANDARD_V2, tier=azure_native.network.ApplicationGatewayTier.STANDARD_V2, capacity=2, ), gateway_ip_configurations=[azure_native.network.ApplicationGatewayIPConfigurationArgs( name="appGatewayIpConfig", subnet=azure_native.network.SubResourceArgs( # You would specify an ID of an existing subnet where you want to deploy the Application Gateway. # The subnet must be dedicated to the Application Gateway, not containing any other resources. id="/subscriptions/{subscription_id}/resourceGroups/{resource_group_name}/providers/Microsoft.Network/virtualNetworks/{vnet_name}/subnets/{subnet_name}", ), )], frontend_ip_configurations=[azure_native.network.ApplicationGatewayFrontendIPConfigurationArgs( name="appGatewayFrontendIp", public_ip_address=public_ip, )], frontend_ports=[azure_native.network.ApplicationGatewayFrontendPortArgs( name="appGatewayFrontendPort", port=80, # You may want to use 443 for HTTPS with SSL termination )], http_listeners=[azure_native.network.ApplicationGatewayHTTPListenerArgs( name="appGatewayHttpListener", frontend_ip_configuration=azure_native.network.SubResourceArgs( id=public_ip.id, ), frontend_port=azure_native.network.SubResourceArgs( id="appGatewayFrontendPort", ), protocol=azure_native.network.ApplicationGatewayProtocol.HTTP, )], backend_address_pools=[azure_native.network.ApplicationGatewayBackendAddressPoolArgs( # This is an array because you can define multiple backend pools for different purposes name="appGatewayBackendPool", )], backend_http_settings_collection=[azure_native.network.ApplicationGatewayBackendHTTPSettingsArgs( name="appGatewayBackendHttpSettings", port=80, # The port used for the backend servers protocol=azure_native.network.ApplicationGatewayProtocol.HTTP, )], request_routing_rules=[azure_native.network.ApplicationGatewayRequestRoutingRuleArgs( name="appGatewayRoutingRule", http_listener=azure_native.network.SubResourceArgs( id="appGatewayHttpListener", ), backend_address_pool=azure_native.network.SubResourceArgs( id="appGatewayBackendPool", ), backend_http_settings=azure_native.network.SubResourceArgs( id="appGatewayBackendHttpSettings", ), rule_type=azure_native.network.ApplicationGatewayRequestRoutingRuleType.BASIC, )], ) # Export the Application Gateway's name and public IP address pulumi.export('appGatewayName', app_gateway.name) pulumi.export('appGatewayPublicIp', public_ip.ip_address)

    In this program, we are:

    • Creating a resource group for our services.
    • Creating a public IP necessary for the Application Gateway.
    • Setting up an Application Gateway with a simple HTTP listener. Note that the subnet and other configurations would need to be replaced with actual values corresponding to your Azure setup.
    • Exporting the name and public IP address of the Application Gateway so we can access this information when the deployment completes.

    This configuration will set up a basic Application Gateway without SSL or a WAF policy. Consider enhancing this setup for real-world applications, especially to secure sensitive information over HTTPS and to protect against malicious attacks with a WAF policy (which would be created using the WebApplicationFirewallPolicy resource).

    For further customization and configuration options, please refer to the official Pulumi documentation for ApplicationGateway and WebApplicationFirewallPolicy.