Repository: flutter
Issue: Document how to publish module App and plugins frameworks in dependency management systems like CocoaPods and Swift Package Manager
Labels: c: new feature,platform-ios,tool,d: api docs,a: existing-apps,c: proposal,P3,team-ios,triaged-ios

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## Use case
Our Flutter application is located in another repository and we use `cocoapods` to manage our dependencies, It is possible to create a flag to generate `podspecs` for all frameworks?  It helps us to use our dependencies remotely in separate repositories.

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## Proposal

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Recently Flutter created `--cocoapods` flag to create a podspec to Flutter. It is possible to create the same way to create podspec for `App.framework`, `plugins` and `FlutterPluginRegistrant.framework`? If possible, create `.zip` file to upload these files in repositories.

**Approach B:** Using [option B](https://flutter.dev/docs/development/add-to-app/ios/project-setup#option-b---embed-frameworks-in-xcode)

```bash
flutter build ios-framework --cocoapods
```
Output:
```text
some/path/MyApp/
└── Flutter/
    ├── Build Mode/
    │   ├── Flutter.podspec
    │   ├── App.zip (include App.framework, FlutterPluginRegistrant.framework and all plugins)
    │   └── App.podspec (include App.framework, FlutterPluginRegistrant.framework and all plugins) 
```
Podfile with locale path:

```ruby
pod 'Flutter', :podspec => 'some/path/MyApp/Flutter/{build_mode}/Flutter.podspec'
pod 'App', :podspec => 'some/path/MyApp/Flutter/{build_mode}/App.podspec'
```

Podfile with remote path:

```ruby
pod 'Flutter', :git => 'repository/Flutter.podspec'
pod 'App', :git => 'repository/App.podspec'
```

**Approach A:** Using [option A](https://flutter.dev/docs/development/add-to-app/ios/project-setup#option-a---embed-with-cocoapods-and-the-flutter-sdk)

Is possible to use `podhelper.rb` remotely?

```podspec
# MyApp/Podfile
target 'MyApp' do
  install_all_flutter_pods(git_path)
end
```