Engine Design

Mon, 01 Jan 0001 00:00:00 +0000

CaD Engine Architecture

The Engine follows a layered architecture with clear separation of concerns:

┌─────────────────────────────────────────┐
│ CaDEngine Interface │ ← Public API
├─────────────────────────────────────────┤
│ cadEngine Implementation │ ← Orchestration Logic
├─────────────────────────────────────────┤
│ ┌──────────┬──────────┬─────────────┐ │
│ │ Cache │ Task │ Watcher │ │ ← Dependencies
│ │ │ Handler │ Manager │ │
│ └──────────┴──────────┴─────────────┘ │
└─────────────────────────────────────────┘

Key architectural patterns:

Dependency Injection via Functional Options

The engine is constructed using a functional options pattern that allows flexible configuration of dependencies:

Engine Interactions

Mon, 01 Jan 0001 00:00:00 +0000

Overall Interaction Overview

Cache Integration

The Engine relies heavily on the Package Cache as its primary interface to repositories:

Opening Repositories

All repository access goes through the cache:

Engine
 ↓
OpenRepository(repositorySpec)
 ↓
Package Cache
 ↓
Repository Adapter (Git)

Process:

Engine receives a Repository CR specification
Calls cache.OpenRepository(ctx, repositorySpec)
Cache returns a Repository interface implementation
Engine uses the repository abstraction for all operations

Benefits of cache-mediated access:

Caching: Frequently accessed repositories remain in memory
Synchronization: Cache handles background repository sync
Abstraction: Engine doesn’t need to know if it’s Git or another backend
Connection pooling: Cache manages repository connections efficiently

Repository Operations

Once a repository is opened, the engine delegates all storage operations:

Engine on Porch Documentation