Handling Workout Requests with SiriKit

At a glance

Project structure

Source bundle/
├── Ascent/
│   ├── AppDelegate.swift
│   └── WorkoutsController.swift
├── AscentFramework/
│   ├── Workout.swift
│   ├── NSUserActivity+Ascent.swift
│   ├── Workout+DictionaryRepresentation.swift
│   └── WorkoutHistory.swift
└── AscentIntentsExtension/
    ├── CancelWorkoutIntentHandler.swift
    ├── EndWorkoutIntentHandler.swift
    ├── IntentHandler.swift
    ├── PauseWorkoutIntentHandler.swift
    ├── ResumeWorkoutIntentHandler.swift
    └── StartWorkoutIntentHandler.swift

Structure observations

• Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
• Primary languages: C/Objective-C header, Swift.
• The verified tree contains 11 project/configuration file(s) and 18 source declaration(s).

Overall architecture

flowchart LR
    N1["AppDelegate"]
    N2["WorkoutsController"]
    N3["CancelWorkoutIntentHandler"]
    N4["Intents APIs"]
    N1 --> N2
    N2 --> N3
    N3 --> N4

Reference code

Ascent/AppDelegate.swift:12 — architecture anchor

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    // ...
    var window: UIWindow?
    // ...
}

Interpretation

The arrows summarize the source-visible entry, role-named types or folders, and framework direction; when nodes come from structural folders, the sequence is a high-level interpretation rather than proof that every adjacent node calls the next. Ownership is claimed only where the next section cites a stored property or assignment. The diagram is intentionally limited to the dominant path into Intents.

Ownership and state

classDiagram
    AppDelegate o-- UIWindow : window
    WorkoutsController o-- WorkoutHistory : workoutHistory
    WorkoutCell o-- UILabel : climbDescriptionLabel
    WorkoutCell o-- UILabel : goalDescriptionLabel

Ownership evidence

Ascent/AppDelegate.swift:15 — stored dependency or nearest verified ownership anchor

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    // ...
    var window: UIWindow?
    // ...
}

Composition arrows indicate a source-visible construction expression or locally owned value state; aggregation means the owner stores or receives a dependency without proving exclusive lifetime ownership.

Concurrency, scheduling, and thread safety

Evidence limit: actor isolation, async/await, or Task creation does not by itself prove background-thread execution; Sendable conformance alone does not prove thread-safe mutation.

No source-visible execution, scheduling, or synchronization boundary was found in the indexed source.

@MainActor/MainActor.run, DispatchQueue.main, and RunLoop.main are reported as distinct isolation, queue, and event-loop mechanisms. A plain Task is kept separate from Task.detached; neither is labeled as a background thread.

State propagation, frameworks, and dependencies

Evidence limit: an import proves a source-level compilation dependency at the cited line; it does not prove runtime use, architectural adoption, or whether a Swift package is a direct application dependency.

receive(on:) describes downstream delivery scheduling, while subscribe(on:) describes upstream subscription/request/cancel scheduling. An import Combine alone establishes neither behavior nor a Store, reducer, Redux, or other application architecture.

Class and protocol design

AscentIntentsExtension/IntentHandler.swift:10 — representative type boundary

protocol IntentHandler: AnyObject {

    func canHandle(_ intent: INIntent) -> Bool

}

The source explicitly defines local protocol relationships: CancelWorkoutIntentHandler → IntentHandler, EndWorkoutIntentHandler → IntentHandler, PauseWorkoutIntentHandler → IntentHandler, ResumeWorkoutIntentHandler → IntentHandler, StartWorkoutIntentHandler → IntentHandler.

Access control

Reference code

Ascent/AppDelegate.swift:43 — representative boundary

    private func handle(_ startWorkoutIntent: INStartWorkoutIntent) -> INStartWorkoutIntentResponse {
        var workoutHistory = WorkoutHistory.load()
        // ...
    }

Swift declarations without a modifier are internal; explicit private, fileprivate, private(set), public, or open entries above are interpreted by language semantics. Objective-C/C samples instead rely on header and implementation boundaries, which are not equivalent to Swift lexical privacy.

Logic ownership and placement

Design patterns

Naming conventions

• Types: Controller: WorkoutsController; Delegate: AppDelegate; Handler: CancelWorkoutIntentHandler, EndWorkoutIntentHandler, IntentHandler, PauseWorkoutIntentHandler, ResumeWorkoutIntentHandler.
• Protocols: IntentHandler.
• Methods: application, handle, applicationDidBecomeActive, tableView, restoreUserActivityState, workout, canHandle, confirm.
• Files: Ascent/AppDelegate.swift, Ascent/WorkoutsController.swift, AscentFramework/Workout.swift, AscentIntentsExtension/CancelWorkoutIntentHandler.swift, AscentIntentsExtension/EndWorkoutIntentHandler.swift, AscentIntentsExtension/IntentHandler.swift.

Architecture takeaways

• AppDelegate is the main source-visible entry or composition anchor for this sample.
• Framework work reaches Intents, AscentFramework, UIKit through a deliberately small high-level chain; the detailed API graph remains inside the cited implementation files.
• Stored-property evidence identifies lifecycle collaboration; it does not by itself prove exclusive object ownership.
• Access-control conclusions separate verified language visibility from the likely design rationale.
• Local protocol relationships provide an explicit substitution boundary.

Source map

• Official Apple documentation