LoopBack Client in Swift 3 - A Simple Example

This is a simple LoopBack client written in Swift using an in-development version of LoopBack iOS SDK.

This basically is a Swift version of the iOS client found in this tutorial: "How-to Build CRUD Enabled iOS Apps with the LoopBack API Server" with the following differences:

• Written in Swift, rather than Objective-C.
• The LoopBack API server used in this demo is created by following Getting started with LoopBack/Create a simple API instead of the one referenced in Step 2 of the original tutorial, since it doesn't seem to exist anymore. Because of this change, the app deals with CoffeeShops instead of Books.
• The client workspace already includes a module-enabled version of the LoopBack iOS SDK framework. The bundled LoopBack.framework is an in-development version of strongloop/loopback-sdk-ios at revhash of 897293f (12/25/2015).
• Swipe-to-delete feature of the table view is added to demonstrate deletion of a model.

How to Try Out

1. Clone the repo: e.g. git clone https://github.com/hideya/loopback-swift-simple-example

• cd test-server
• npm install to install the node modules required by the server.
• node . to run the server.
• Open the client Xcode project from swift-client/CoffeeShops/CoffeeShops.xcodeproj
• Build and run the client by typing command⌘-R.

Key Code Fragments

The following code fragments show key parts of LoopBack iOS SDK usage with Swift.

Model definition:

import LoopBack

class CoffeeShop: LBPersistedModel {
    var name: String!
    var city: String!
}

class CoffeeShopRepository: LBPersistedModelRepository {
    override init() {
        super.init(className: "CoffeeShops")
    }

    class func repository() -> CoffeeShopRepository {
        return CoffeeShopRepository()
    }
}

Instantiation of the adapter and the repository:

    static let adapter = LBRESTAdapter(url: URL(string: "http://localhost:3000/api"))
    static let coffeeShopRepo = adapter?.repository(with: CoffeeShopRepository.self) as! CoffeeShopRepository

Find all the models:

    coffeeShopRepo.all(
            success: { (models) -> Void in
            // success block
            let tableData = models as! [CoffeeShop]
            ...
        },
        failure: { (error: Error?) -> Void in
            // failure block
            ...
        })

Create a new model:

    let newCoffeeShop = coffeeShopRepo.modelWithDictionary(nil) as! CoffeeShop
    newCoffeeShop.name = nameField.text!
    newCoffeeShop.city = cityField.text!

    newCoffeeShop.save(
            success: { () -> Void in
            // success block
            ...
        },
        failure: { (error: Error?) -> Void in
            // failure block
            ...
        })

Delete an existing model:

        coffeeShop.destroy(
                success: { () -> Void in

            // success block
            ...
        },
        failure: { (error: Error?) -> Void in
            // failure block
            ...
        })