RxCocoaNetworking

An extremely lightweight networking framework built on top of RxCocoa, tailored for testing with RxTest and inspired by Moya.

• Requirements
• Usage
• Installation
• Contributing
• License

While Moya is built on top of Alamofire and provides an Rx extension with Observable signatures, RxCocoaNetworking is built on top of RxCocoa, which already provides extensions to NSURLSession with Observable signatures. RxCocoaNetworking was made for you if:

• ✅ you love how Moya keeps your network layer clean, readable and testable;
• ✅ the power of Alamofire+Moya is too much for your needs;
• ✅ your project already depends on RxCocoa.

... and extra points if:

• ✅ you'd like to use RxTest for testing delayed stubs;
• ✅ you don't like to implement sampleData in your production target;
• ✅ you feel you could have less code for the simple APIs you use.

Note though that this is by no means a full replacement to Alamofire+Moya. For example, you may miss features which will only ever be supported if RxCocoaNetworking is kept extremely lightweight, e.g.:

• ❌ anything other than Data on successful responses;
• ❌ file upload;
• ❌ plugins (interceptors).

... in which case Alamofire+Moya would be a better bet.

This framework was made possible thanks to the network request handling already embedded in RxCocoa, together with Swift 4.1's conditional conformance (see ReactiveURLSessionProtocol).

Requirements

• 📱 iOS 9.0+ / Mac OS X 10.11+ / tvOS 10.0+ / watchOS 3.0+
• 🛠 Xcode 9.3+
• ✈️ Swift 4.1+
• ⚠️ RxCocoa
• 🔥 Does not require Alamofire

Usage

If you're already used to Moya, the good news is that RxCocoaNetworking (intentionally) has a very similar architecture! All you need is to create a structure to represent your API - an enum is recommended - and have it implement one of the TargetType protocols. Requests to your API are managed by a Provider which is typed to your concrete TargetType.

Both if you're used to Moya or not, the other good news is that you can base off the example ExampleAPI and its spec.

Summarized `ExampleAPI`

enum ExampleAPI {
  // Endpoints as cases:
  case rate(movieID: String, rating: Float)
  case reviews(movieID: String, page: Int)
}

extension ExampleAPI: ProductionTargetType {
  // Your API's base URL is usually what determines an API enum.
  var baseURL: URL { return URL(string: "...")! }
  
  var path: String {
    switch self {
    case .rate(let movieID, _):
      return "/movie/\(movieID)/rating"
    case .reviews(let movieID, _):
      return "/movie/\(movieID)/reviews"
    }
  }
  
  var task: Task {
    // Specify GET/POST/etc., body and query parameters:
    switch self {
    case .rate(_, let rating):
      return Task(method: .post, dictionaryBody: ["value": rating])
    case .reviews(_, let page):
      return Task(parameters: parameters)
    }
  }
  
  var headers: [String : String]? { return nil }
}

extension ExampleAPI: TargetType {
  var sampleData: Data {
    ...
  }
}

Regular network requests (no stubbing):

let provider = Provider<ExampleAPI>()

The default Provider parameters is most often what you'll use in production code.

Immediately stubbed network responses:

let provider = Provider<ExampleAPI>(stubBehavior: .immediate(stub: .default))

stub: .default means the sampleData from your API will be used. Other Stub types allow you to specify different responses inline.

Note: if you implement ProductionTargetType, then stub: .default is not available, because sampleData is not required by that protocol 👌 You can always implement TargetType separately, for example, in the Tests target.

RxTest-testable delayed stubbed network responses:

let testScheduler = TestScheduler(initialClock: 0)
let provider = Provider<ExampleAPI>(stubBehavior: .delayed(time: 3,
                                                           stub: .error(SomeError.anError)),
                                    scheduler: testScheduler)

An error will be emitted 3 virtual time units after the subscription occurs.

Installation

Dependency Managers

CocoaPods

CocoaPods is a dependency manager for Cocoa projects. You can install it with the following command:

$ gem install cocoapods

To integrate RxCocoaNetworking into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '9.0'

pod 'RxCocoaNetworking', '~> 0.2.2'

Then, run the following command:

$ pod install

Carthage

Carthage is a decentralized dependency manager that automates the process of adding frameworks to your Cocoa application.

You can install Carthage with Homebrew using the following command:

$ brew update
$ brew install carthage

To integrate RxCocoaNetworking into your Xcode project using Carthage, specify it in your Cartfile:

github "gobetti/RxCocoaNetworking" ~> 0.2.2

Swift Package Manager

To use RxCocoaNetworking as a Swift Package Manager package just add the following in your Package.swift file.

// swift-tools-version:4.1
import PackageDescription

let package = Package(
    name: "HelloRxCocoaNetworking",
    dependencies: [
        .package(url: "https://github.com/gobetti/RxCocoaNetworking.git", .upToNextMajor(from: "0.2.2"))
    ],
    targets: [
        .target(name: "HelloRxCocoaNetworking", dependencies: ["RxCocoaNetworking"])
    ]
)

Manually

If you prefer not to use either of the aforementioned dependency managers, you can integrate RxCocoaNetworking into your project manually.

Git Submodules

• Open up Terminal, cd into your top-level project directory, and run the following command "if" your project is not initialized as a git repository:

$ git init

• Add RxCocoaNetworking as a git submodule by running the following command:

$ git submodule add https://github.com/gobetti/RxCocoaNetworking.git
$ git submodule update --init --recursive

• Open the new RxCocoaNetworking folder, and drag the RxCocoaNetworking.xcodeproj into the Project Navigator of your application's Xcode project.

  It should appear nested underneath your application's blue project icon. Whether it is above or below all the other Xcode groups does not matter.

• Select the RxCocoaNetworking.xcodeproj in the Project Navigator and verify the deployment target matches that of your application target.

• Next, select your application project in the Project Navigator (blue project icon) to navigate to the target configuration window and select the application target under the "Targets" heading in the sidebar.

• In the tab bar at the top of that window, open the "General" panel.

• Click on the + button under the "Embedded Binaries" section.

• You will see two different RxCocoaNetworking.xcodeproj folders each with two different versions of the RxCocoaNetworking.framework nested inside a Products folder.

  It does not matter which Products folder you choose from.

• Select the RxCocoaNetworking.framework.

• And that's it!

The RxCocoaNetworking.framework is automagically added as a target dependency, linked framework and embedded framework in a copy files build phase which is all you need to build on the simulator and a device.

Embedded Binaries

• Download the latest release from https://github.com/gobetti/RxCocoaNetworking/releases
• Next, select your application project in the Project Navigator (blue project icon) to navigate to the target configuration window and select the application target under the "Targets" heading in the sidebar.
• In the tab bar at the top of that window, open the "General" panel.
• Click on the + button under the "Embedded Binaries" section.
• Add the downloaded RxCocoaNetworking.framework.
• And that's it!

Contributing

Issues and pull requests are welcome!

Once you clone the project, all you need to do before building it is to install the Carthage dependencies:

$ carthage bootstrap

Then to successfully run the unit tests, you need to have the wiremock script running in the background:

$ ./script/wiremock.sh

Author

Marcelo Gobetti @mwgobetti

License

RxCocoaNetworking is released under the MIT license. See LICENSE for details.