Constellation Runtime Architecture & Its Components.

Constellation Runtime Architecture

The Constellation Runtime architecture consists of two main parts:

• server-side components built in Pega Infinity
• client-side components

1. Server-side: Pega Infinity Platform

• This is where the Constellation Digital Experience (DX) API is implemented.
• For Pega Constellation, DX API Version 2 is used.
• DX API V2 is a RESTful API that provides both UI metadata and contextual data in a single response.

2. Client-side Components

a. Constellation JS Engine and Public JS APIs (PCore and PConnect)

• The Constellation JS Engine is responsible for overall runtime UI orchestration.
• It’s built using ES6 (ECMAScript 2015) and is framework-agnostic, supporting React, Angular, and Web Components.
• Key components include:
  • Bootstrap for application initialization
  • Environment Info for runtime configuration
  • Asset Loader for managing scripts, styles, and images
  • Rest Client for HTTP requests
  • State Manager (Redux) for application state management
  • PubSub and Messaging Service for component communication
  • CRUD Manager for data operations
  • Component Manager for UI component management
  • Public JS APIs include features like Promises for async operations, Mashup Bridge, and various processors (Property, Expression, When, Localization).

b. Constellation Front End React Bridge

• This bridge connects the Constellation JS Engine with the presentation layer.
• It includes Constellation DX components provided by Pega, available on GitHub (Constellation UI gallery).
• It also supports custom DX components for extending functionality (Web Component Builder).

c. Presentation Component

• Available at design.pega.com
• Manages the user interface and interactions.

3. DX API V2

• Provides both UI metadata and contextual data in a single response.
• The primary consumer of the DX API is the Constellation JS Engine.

4. Additional Components

• Service Broker: Acts as an intermediary connecting various services.
• Constellation Messaging Server: Manages messaging services and includes Web Sockets for real-time communication.

This architecture follows modern design paradigms such as stateless architecture, client orchestration, and modular design. It allows for a more streamlined, manageable, and efficient system compared to traditional architectures. The Constellation architecture’s modular and flexible design enables it to support a wide variety of network types, devices, and environments while reducing design and installation resources and time.

Pega Site References

1. Characteristics of Constellation Architecture
2. Anatomy of Constellation UI
3. Constellation Architecture
4. Build Constellation DX Components