iOS dependency management and packaging - ios

I'm completely new to iOS development and coming from an Android background. I was starting to look at what alternatives are out there for dependency management in iOS and found out that CocoaPods seems to be the most prevalent option.
After reading a lot of links about this topic I'm kinda at a loss and wondering what is the usual way dependencies are handled in iOS.
I have two questions:
1) What would the equivalent of using gradle to generate library (.aar) projects be in iOS? If there's any equivalent option. From what I've seen one can wrap static libraries and headers into frameworks and these can be used in other apps, is this the standard way to do it?
2) If (1) is correct, does CocoaPods offer a mechanism to add frameworks as dependencies?

I don't have a Android background but from what I understand of .aar files CocoaPods does something very similar. CocoaPods uses .podspec files (described here) to generate static libraries (and soon dynamic frameworks which are new in iOS 8) that are then linked into your project.
A podspec can define source files, assets, libraries, or frameworks that a source vendors for linking into your application. So yes it does support adding frameworks as dependencies, although until iOS 8 frameworks were not supported at all on iOS.
As far as the 'standard' way to do it, I think that's based on opinion. There are a few general ways to include dependencies you can choose from.
Drag files, frameworks, and whatever else you need into your project manually. Updating these is more difficult and that also means you have to configure your .xcodeproj depending on what features that library needs (such as ARC)
Drag a provided .xcodeproj into your project, and link the relevant target from the given project. This can be nice if the library provides a project that can build a framework or static library, in this case you'd pull in that library but their project would handle custom compiler flags.
Do either of the above while including them as git submodules. Assuming nothing massive changes in the project this helps a lot with updating your dependencies.
Use CocoaPods. CocoaPods will handle all the custom linking and updates based on semantic versioning (usually).
Use Carthage. Carthage is an in- between CocoaPods and the .xcodeproj solution. It will download code based on semantic versions defined by git tags, then you drag the generated frameworks into your project.
All of these options have pros and cons and the decision normally comes down to how you feel about the control you have over the inclusion of the library, and how automated you want it to be.

I do not have android nor iOS background however I've been developing a CI tool for both platforms and here are the answers
As You mentioned this a framework and pods (libraries) from cocoapods are distributed that way. For instance, have a look at Apphance. When spec is clicked it's visible that this library will be accessible as a Apphance-Production.framework.
You add pods to Podfile and download them with pod install command. This command will made classes from Apphance accessible from the code. Some people do commit downloaded pods, other not (it's like adding jars or aars to source control).

Related

xcode how to develop with frameworks

Thanks for spending time reading my question.
I've been working as an iOS developer for more than 2 years and today I still feel shame because I don't know how to deal with frameworks. I've build some projects using my own frameworks, but I've never understood exactly what's the best practice doing this.
Lets see the following example:
Project -> FrameworkA -> AFNetworking - Charts - FMDB - more
So, I have a big FrameworkA with mostly all the app behavior and then a small project referencing this FrameworkA and customizing just icons, texts and images. I use to manage dependencies with CocoaPods and I would like to use it with FrameworkA. By this I could reference external libraries easily, but it seems it doesn't work for frameworks, only for projects. So, my questions is: how can I add AFNetworking, Charts, FMDB, etc to my FrameworkA and then reference the framework form my project?
I appreciate if you can give me some idea using CocoaPods or any other dependency manager. I don't like the old way by doing this manually.
I hope my case is clear.
Thanks!
It sounds like you are asking how to embed external frameworks such as AFNetworking into a framework you are developing, and then use that framework in your app.
This is what's known as embedded frameworks where one framework is stored within another. Generally speaking it's not a great idea and should be avoided because it can cause version clash issues.
The way I'd recommend doing this is to use CocoaPods or Carthage to link the external frameworks (AFNetworking, etc) into your framework project. But do to try to embedded them.
Then in your app project, again use CocoaPods or Carthage to link in your framework (you won't need to link the external ones unless you are directly using them in the app code). Then add the necessary build steps to copy both your framework file and all the external framework files to the finished app's framework directory.

Cocoa Touch Framework Swift with embed libraries

I am working on a suite of applications that contain common modules.
 
I want to store the common modules in a Cocoa Touch Framework.
This framework may also contain the libraries and Alamofire and SwiftyJSON because they are widely used in the modules.
 
Currently, despite the many tutorials, articles, etc. read on the internet, I cannot get a stable solution.
Is it possible to integrate the frameworks Alamofire and SwiftyJSON within the framework custom or is it better to integrate them in the different projects consuming the framework (they will also need individually) ?
 
Is it possible to generate a framework running on the simulator and on the phone (whatever methods: subproject or not, dynamic or static library, fat library) ?
You can absolutely do this. You currently have three options for setting this up for development and two options for deployment.
Development
Git Submodules
Git submodules are a great way to bring additional libraries into your project's repository to embed in your project. All you need to do is add the submodule, then drag the Xcode project of that library into your Xcode project so it's nested inside your project. Then you need to add the framework as a link target to your library.
Carthage
Carthage also supports git submodules through the --use-submodules flag. All you need to do is install carthage through homebrew, then create a Cartfile that adds Alamofire and SwiftyJSON using the following command.
carthage update --use-submodules
CocoaPods
CocoaPods is a dependency management system that allows you to easily pull in and deploy different versions of a given library. Since both Alamofire and SwiftyJSON support CocoaPods, you could create a Podfile, and run pod install to pull the pods into your library. I would not recommend this though as this is a pretty heavy weight approach. Instead, I would recommend using either Git Submodules or Carthage for development.
Deployment
Deployment is a MUCH different situation. Currently, there are two fairly robust deployment mechanisms for iOS and OSX that are in wide use in the OSS community (including Alamofire and Carthage).
Carthage
If you imported your git submodules using Carthage, then you may already be completely supporting Carthage deployments. It depends on whether you used a Cartfile.private file to pull in your dependencies. Given what you're trying to do, I doubt that you would use a private Cartfile and would instead use the public one. This means that you should be good to go right out of the box. Awesome!
CocoaPods
CocoaPods is much different than Carthage and has some big advantages over Carthage, at a cost. You need to create a podspec file and push that into a public or private spec repo. Then anyone can pull your pod into their project using a Podfile.
Summary
As you can see, there are MANY options here. I would highly recommend using Carthage to pull in your git submodules, then supporting both Carthage and CocoaPods for deployment. I know that's a lot of effort though, so you may want to focus on one or the other. Sorry for the massive amount of links and information, but you question leads me to believe that you would greatly benefit from all these various sources.
Hopefully that helps get you on your way to becoming a dependency development and deployment ninja.

Combine Cocoapods and Carthage

I'm creating a Swift framework that is dependent on several other third party frameworks. Both these other frameworks support Carthage and Cocoapods.
Is there any way I can make my own framework support installing using both Carhage and Cocoapods? Or is just not achievable and should I just pick one?
You can definitely make your framework available with both CocoaPods and Carthage. This is the path that I would recommend to allow your users to use whatever solution they prefer. Also note that setting a framework up to work with Carthage also makes it much easier for users who want to use your library without either of these solutions.
On a high level, for CocoaPods you'll want to create a podspec that lists your dependencies there. This way CocoaPods will manage downloading and configuring them along with resolving them against other user dependencies. See more here.
For Carthage you'll want to configure your project with framework targets for the platforms you support and add your dependencies in your Cartfile. More on that here
Combining both is actually not difficult. With my framework I have started with CocoaPods template containing Example and Pod directories. In the example project I created a new Cocoa Touch Framework target, made sure this target is Shared (in Product - Schemes - Managed Schemes) and dragged content of my Pod/Classes directory to the project (with unchecked Copy items if needed and added Target Membership only to this newly created framework).
This should be enough, Carthage should find this shared scheme and use it. Just keep in mind you have to commit changes and create a new git tag before using your framework from Carthage.

How to install projects without cocoa pods?

I have seen various libraries on GitHub that look useful, but only list CocoaPods as an install method. I'm not sure I want to be dependent on CocoaPods, because I'm wary of Apple breaking it in some future OS X/Xcode update. Is there a way to get these libraries into my Xcode project without using CocoaPods?
Role of CocoaPods is to automate and simplify the process, but you don't need to use CocoaPods if you don't want to.
In case of "manual installation", usually it would be:
download the project from GitHub
add the files to Xcode
import headers
But there is no universal recipe for every project, it may slightly differ from case to case, but usually it boils down to previously mentioned.
The best way if you don't want to use CocoaPods is to read the project documentation, and study examples if there are any.
Of course there is. Basically you need to download the library project, drag the project into your own project, do some library dependency setup and you're done.
For details, check out https://github.com/Alamofire/Alamofire for manually adding a Swift library. And https://github.com/jverkoey/ObjQREncoder for manually adding a Objective-C library to your project.
The only way to install things without Cocoapods is to just drag the source code of other projects into your class. For example, most Github projects can be installed via Cocoapods, or you can just drag the relevant source code into your projects. You don't need to drag in all of the project resources, all you need is usually class files

Working with libraries in Xcode (i.e. ImageMagick, AdMob) include in project or link?

(This may have been asked many times before but I'm not seeing it in the suggested questions/search)
Assuming I have 3rd party code libraries like ImageMagick and AdMob which I may use in multiple iOS projects, is it "better" to link to them or to include them in the project?
I'm using XCode with git. In one project I have included them so they are all under source control. In another project they are linked and I am getting "?" (question mark) icons next to all the library files. Confusing.
My honest suggestion for using 3rd party libraries would be to use CocoaPods for as many as you can get your hands on. Which there is a good chance all would be available.
Reasons why CocoaPod inclusion is better:
Easy to add and remove from project
Automatic linkage to your project
Easy to update after including
Drawbacks to CocoaPod use:
Doesn't help you if your library isn't included
You don't want to use the newly created xcworkspace instead of xcodeproj
The reasons not to use them are pretty weak, and I will admit to be biased in favor of them. I have had to work with lots of static libraries and frameworks, most of which are created in house. CocoaPods has made sharing, maintaining, and installing libraries a piece of cake. So please consider using them in your project.
If CocoaPods aren't your thing or not an option, linking against the library or framework is probably second best. If you drag and drop into your project (while easy) makes updating later kind of a pain. Dynamic linking allows you to swap them out from the file directory without having to change anything in your Xcode project. It requires a bit more finesse to get set up, but ultimately will be better for the long haul. IMO anyway.

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