The beautiful way to chain your services logic

ios, lagoon, macos, nsoperation, nsoperationqueue, operations, swift
pod try Lagoon



Build Status CocoaPods Carthage Compatible GitHub license Platforms

Lagoon is a framework written in Swift that makes it easy for you to organize your service layer


  • Asynchronous operations
  • SOLID out of the box
  • Very simple writing unit tests
  • Reusable business logic
  • Generics


Look at the simple example

Here we convert our string to number, increment and decrement it, multiply and divide by digits. Let's create example operations:

/// Convert String to Int
class ConvertOperation: ChainableOperationBase<String, Int> {
    override func process(inputData: String, success: (Int) -> (), failure: (Error) -> ()) {
        if let result = Int(inputData) {
        } else {
            failure(NSError(domain: "com.incetro.Lagoon.Example", code: 1, userInfo: nil))

/// Increment the given number
class IncrementOperation: ChainableOperationBase<Int, Int> {
    override func process(inputData: Int, success: (Int) -> (), failure: (Error) -> ()) {
        success(inputData + 1)

/// Decrement the given number
class DecrementOperation: ChainableOperationBase<Int, Int> {
    override func process(inputData: Int, success: (Int) -> (), failure: (Error) -> ()) {
        success(inputData - 1)

/// Multiply the given number
class MultiplicationOperation: ChainableOperationBase<Int, Int> {
    let mult: Int
    init(with mult: Int) {
        self.mult = mult
    override func process(inputData: Int, success: (Int) -> (), failure: (Error) -> ()) {
        success(inputData * self.mult)

/// Make array of digits from the given number
class ArrayOperation: ChainableOperationBase<Int, [Int]> {
    override func process(inputData: Int, success: ([Int]) -> (), failure: (Error) -> ()) {
        var result: [Int] = []
        var number = inputData
        while number > 0 {
            result.append(number % 10)
            number = number / 10

And make chain convert -> increment -> decrement -> multiplication -> array

let strings = ["123", "4", "56a", "a", ""]
for string in strings {
    let convert   = ConvertOperation()
    let increment = IncrementOperation()
    let decrement = DecrementOperation()
    let mult      = MultiplicationOperation(with: 125)
    let array     = ArrayOperation()
    /// Create chain
    let operations = [convert, increment, decrement, mult, array]
    /// We expect Int array as output type
    let compoundOperation = CompoundOperation.default(withOutputDataType: [Int].self)
    /// Setup compound operation
    compoundOperation.configure(withChainableOperations: operations, inputData: string, success: { result in
    }, failure: { error in
    /// Start it!
    Lagoon.add(operation: compoundOperation)

Advanced usage

Okay, how can you use it in the real projects? Look at this.

// MARK: - RequestDataSigningOperation
class RequestDataSigningOperation: ChainableOperationBase<RequestDataModel, RequestDataModel> {
    private let requestSigner: RequestDataSigner
    init(withRequestSigner requestSigner: RequestDataSigner) {
        self.requestSigner = requestSigner
    override func process(inputData: RequestDataModel, success: (RequestDataModel) -> (), failure: (Error) -> ()) {
        let signedRequestDataModel = requestSigner.signRequestDataModel(inputData)

// MARK: - RequestConfigurationOperation
class RequestConfigurationOperation: ChainableOperationBase<RequestDataModel, URLRequest> {
    private let requestConfigurator: RequestConfigurator
    private let method: HTTPMethod
    private let serviceName: String?
    private let urlParameters: [String]
    private let queryType: QueryType
    init(configurator: RequestConfigurator, method: HTTPMethod, type: QueryType, serviceName: String?, urlParameters: [String]) {
        self.method = method
        self.queryType = type
        self.serviceName = serviceName
        self.urlParameters = urlParameters
        self.requestConfigurator  = configurator
    // MARK: - ChainableOperationBase
    override func process(inputData: RequestDataModel, success: (URLRequest) -> (), failure: (Error) -> ()) {
        let request = requestConfigurator.createRequest(withMethod:       self.method,
                                                        type:             self.queryType,
                                                        serviceName:      self.serviceName,
                                                        urlParameters:    self.urlParameters,
                                                        requestDataModel: inputData)

/// And other operations...
/// Then use it to make network chain

let operations = [

let compoundOperation = CompoundOperation.default(withOutputDataType: User.self)
compoundOperation.maxConcurrentOperationCount = 1
compoundOperation.configure(withChainableOperations: operations, inputData: inputData, success: success, failure: failure)
Lagoon.add(operation: compoundOperation)


  • iOS 8.0+ / macOS 10.9+
  • Xcode 8.1, 8.2, 8.3, and 9.0
  • Swift 3.0, 3.1, 3.2, and 4.0


  • If you found a bug, open an issue.
  • If you have a feature request, open an issue.
  • If you want to contribute, submit a pull request.



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

$ gem install cocoapods

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


target "<Your Target Name>" do
    pod "Lagoon"

Then, run the following command:

$ pod install


If you prefer not to use any dependency managers, you can integrate Lagoon into your project manually.

Embedded Framework

  • 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 Lagoon as a git submodule by running the following command:

    $ git submodule add
  • Open the new Lagoon folder, and drag the Lagoon.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 Lagoon.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 Lagoon.xcodeproj folders each with two different versions of the Lagoon.framework nested inside a Products folder.

    It does not matter which Products folder you choose from, but it does matter whether you choose the top or bottom Lagoon.framework.

  • Select the top Lagoon.framework for iOS and the bottom one for OS X.

    You can verify which one you selected by inspecting the build log for your project. The build target for Lagoon will be listed as either Lagoon iOS, Lagoon macOS.

  • And that's it!

    The Lagoon.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.


incetro, Inspired by COOperation


Lagoon is available under the MIT license. See the LICENSE file for more info.