Swift Package Manager (SwiftPM) vs Cocoapods

Table of Contents

Abstract

Today we will talk about dependency managers in iOS and compare their advantages and disadvantages. Finally, we learn how to use those to add dependencies to your project.

Dependencies

When we build applications, we often use code from other developers writing to build more powerful applications more quickly. In your projects, we can make an easy animation to hide or show the button. But if you want to add a complex animation to your project that’s not built-in. Such as import lottie animation into your projects to load and renders animations and vectors exported in the JSON format. So,

Dependency managers in iOS development

There are three main dependency manager tools when developing iOS applications:

• Swift Package Manager
• CocoaPods
• Carthage

Swift Package Manager

The Swift Package Manager is a tool for managing the distribution of Swift code. It’s integrated with the Swift build system to automate the process of downloading, compiling, and linking dependencies. The Package Manager is included in Swift 3.0 and above. SwiftPM is a cross platform build system that is available for MacOS and Linux. Apple published an introduction video Getting to Know Swift Package Manager – Apple WWDC 2018 and SwiftPM has been documented.

Package structure

SwiftPM created the following package structure. Source files are put in Sources and test files are put in Tests. Here is an example:

├── Package.swift
├── README.md
├── Sources
│   └── helloworld
│       └── main.swift
└── Tests
    ├── LinuxMain.swift
    └── helloworldTests
        ├── XCTestManifests.swift
        └── helloworldTests.swift

Swift Package

The most inportant file is call Package.swift. This file use the PackageDescription library in the package manifest to list dependencies, configure localized resources, and set other configuration options.

/ swift-tools-version:4.2
// The swift-tools-version declares the minimum 
// version of Swift required to build this package.

import Packagecontent

let package = Package(
    name: "helloworld",
    dependencies: [
        // Dependencies declare other packages that this package depends on.
        // .package(url: /* package url */, from: "1.0.0"),
    ],
    targets: [
        // Targets are the basic building blocks of a package. 
        // A target can define a module or a test suite.
        // Targets can depend on other targets in this package, 
        // and on products in packages which this package depends on.
        .target(
            name: "helloworld",
            dependencies: []),
        .testTarget(
            name: "helloworldTests",
            dependencies: ["helloworld"]),
    ]
)

How to use

Package Resolution

With the package dependencies configured in the SwiftPM, Xcode will download the packages and resolve dependencies at the build time. When you setting dependencies, you have some options:

• By version: Next version, up to next minor, …
• By branch
• By commit

Adding a Package to your Project

To add a package dependency to your Xcode project, select File > Swift Packages > Add Package Dependency and enter its repository URL. You can also navigate to your target’s General pane, and in the “Frameworks, Libraries, and Embedded Content” section, click the + button, select Add Other, and choose Add Package Dependency. For more information, you can view all at adding-package-dependencies-to-your-app -appledoc

Create a Module and Add a Local Package with SwiftPM

As you develop your app, organize its code in a modular way to keep it maintainable by creating Swift packages and using them as local packages.

1. Open your Xcode project and create a local Swift package as part of your project by selecting File > New > Swift Package.

2. Choose a project and a group, but don’t create a new Git repository if your app is already under version control; then create the new Swift package.

3. Move your code to the new package in the Project navigator and make any needed updates to the package manifest.

4. Select your project in the Project navigator, then select your app target and navigate to its General pane.

5. Click the + button in the “Frameworks, Libraries, and Embedded Content” section, select the local package’s library product, and add it as a dependency.

When you organize your app’s codebase using local packages, your Swift package’s code is part of the same repository as your app’s code. As you create more apps, consider moving local packages to their own Git repositories, and add them to your apps as a package dependency to reuse code across apps. You may even consider sharing them with other developers. For more information, see Publishing a Swift Package with Xcode.

You can check library support SwiftPM at: https://swiftpackageregistry.com/

CocoaPods

CocoaPods is a dependency manager for Swift and Objective-C Cocoa projects. It has over 91 thousand libraries and is used in over 3 million apps. CocoaPods can help you scale your projects elegantly.

Installing Cocoapods

Cocoapods is built on top of Ruby, so you would need to install that in your system before using Cocoapods.

Then, you can install using this command: sudo gem install cocoapods

Using Cocoapods

Open Terminal and go to your Xcode project directory. Afterthat, run command bellow:

pod init

The pod file is generated, so you can config the like like:

platform :ios, '8.0'  
use_frameworks!  
target '12Bay' do  
	pod 'TTBaseUIKit'
end

Carthage

It is the another dependency manager. Carthage has been written in swift language. It will not change anything in Xcode project. It builds framework binaries using xcodebuild but user needs to integrate those libraries into project. To know more about Carthage click here

Supported Platforms

All Apple platforms, iOS, tvOS, watchOS, and macOS. Carthage command line tool works only on a Mac.

Advantages/Disadvantages

Advantages

Disadvantages

Conclusion

Oki, that was it. Through this post, I found it at this point we should use CocoaPods instead of Swift Package Manage. Because SwiftPM is still very young and not all libraries support it. But,

Swift Package Manage is the future of dependency management for any Swift project

So, In the next post, we will talk about how to update iOS cocoapod library to support Swift Package Manager. Thank for reading this post. If you enjoyed it, please share it with others and see you next post.

Posts in this Series

• How to Update Current Cocoapod Lib to Support SwiftPM
• Swift Package Manager (SwiftPM) vs Cocoapods
• TTBaseUIKit - Framework to Build UI Programmatically
• Natural Language Processing on Ios Application Implement Viper Clean Architecture in an Ios App
• Basic Ci Cd Gitlab Fastlane
• The VIPER Architecture