Configfacets Example: Deployment Configuration

In this example, we'll explore the deployment configuration for Istio. The Istio ingress controller starts with an IngressGateway, which acts as an entry point for external traffic. It receives incoming requests and processes them based on the Gateway resource, which defines hostnames, ports, and protocols. The IngressGateway then routes the traffic to the appropriate VirtualService, which specifies how requests should be forwarded to the corresponding backend services within the mesh.

Requirements

• In both environments, all hosts listen on port 443, and the IngressGateway requires an additional NodePort listener on port 30002.
• The configuration for host setup in the Gateway resource and the Istio IngressGateway configuration must be managed within the same endpoint, allowing for easy installation and removal as needed.

Design Decisions

The Configfacets Service data structure is designed to generate configurations dynamically based on templates, overrides, and values. Additionally, it supports the creation of multiple configurations, making it an efficient solution for this use case.

Istio Services Request Context

The Istio Services Request Context provides a dynamic way to configure Istio resources by allowing environment-based filtering at runtime.

{
    "facets": [
        "env:{{ env }}"
    ],
    "globalvars": {
        "__NS_ID__": "istio",
        "__SVC_ID__": "loadbalancer",
        "__GATEWAY_ID__": "gateway"
    }
}

• The {{ env }} placeholder allows runtime substitution with values such as staging or prod.
• The resulting context is then applied to Gateway Configuration and Istio LoadBalancer

Execution

Request Body:

{
    "env": "prod"
}

Step 1

During execution, the env value is injected into the Istio Services Request Context, replacing {{ env }} with "prod".

A filter ("env:prod") is applied to the Example Inc - Values, extracting the relevant configuration values.

Step 2

The Gateway Configuration are executed as per execution settings and final template is derived

The Istio LoadBalancer are executed as per execution settings and final template is derived

Step 3

The final values derived from Step 1 are applied to Step 2