iOS Dependency Management
As an iOS developer, you certainly use a third-party libraries or a source code made by others to extend your app’s abilities. At first, it seems easy, just drag and drop some source code or libraries in your Xcode project or drag and drop an entire subproject into the parent project and you are done.
Just imagine how difficult it would be if you had to implement everything from scratch!
However, this has several disadvantages:
There’s no central place where you can see all your third party libraries that are available.
It’s difficult to find the updated version of the library you used especially if several libraries need to be updated together.
Third party libraries is wasting space in your project.
If the subproject is updated by its owner, your code is out of date.
A dependency management tool called CocoaPods can help you to solve these issues.
CocoaPods is installed through RubyGems, a package management system for Ruby programming language, which comes with a standard OS X install.
To install CocoaPods
$ sudo gem install
Complete the setup of CocoaPods environment
$ pod setup
Navigate to the directory containing your App project
$ cd ~/Path/Directory/Folder/App
Next enter this command
$ pod init
This will create a default Podfile for your project. Podfile should look like this
# Uncomment this line to define a global platform for your project # platform :ios, '6.0'$ pod install target 'App' do end
A Podfile is where the dependencies of a project are listed.
Add dependency in Podfile CocoaPods follows Semantic Versioning conventions
pod 'AFNetworking', '2.5.1'
This tells CocoaPods that you want to include AFNetworking version 2.5.1 as a dependency for your project.
Once all of the dependencies have been specified, they can be installed with the following command
$ pod install
CocoaPods will recursively analyze the dependencies of each project, resolving them into a dependency graph, and serializing into a Podfile.lock file. Podfile.lock keeps track of dependencies version need to be installed.
Pods directory - where all dependencies are stored.
xcworkspace - should be used from that point onward. This allows the original xcodeproj file to remain unchanged.
CocoaPods will create a new Xcode project that creates static library targets for each dependency, and then links them all together into a libPods.a target.
Subsequent invocations of pod install will add new pods or remove old pods according to the locked dependency graph.
Update the individual dependencies of a project
$ pod update
Understanding what’s happening behind the scenes can only help you make better apps.
We’ve walked through the entire process, from installing tools, adding sources, creating the .xcodeproj and all its components, to writing everything to disk.
So next time, run the following command and watch the magic happen.
$ pod install --verbose
CocoaPods is one example of the great work being done on Objective-C infrastructure. And its goal is to improve the discoverability of, and engagement in, third-party open-source libraries. And it’s only getting better.
To know more, read through the CocoaPods Guides for finer details of using CocoaPods.