Multiplatform Http Client

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Starting with Ktor 0.9.4, the HTTP Client supports several platforms, using the experimental multiplatform support that was introduced in Kotlin 1.2.

Right now, the supported platforms are JVM, Android and iOS, but in future versions, there will be more supported.

Android

For Android, in your project’s build.gradle you just have include the following artifact to your dependendices block:

dependencies {
    // ...
    implementation "io.ktor:ktor-client-android:$ktor_version"
    // ...
}

You can then use Android Studio, or gradle to build your project.

iOS

In the case of iOS, you have to use Kotlin/Native, and analogously to android, you have to put this artifact as part of the dependencies block.

dependencies {
    // ...
    implementation "io.ktor:ktor-client-ios:$ktor_version"
    // ...
}

In the case of iOS, we normally create a .framework, and the application project is a normal XCode project written either in Swift or Objective-C that includes that framework. So you first have to build the framework using the gradle tasks exposed by Kotlin/Native, and then open or build the XCode project.

Common

For multiplatform projects that for example share code between Android and iOS, we can create a common module. That common module can only access APIs that are available on all the targets. Ktor HTTP Client exposes a common module that can be used for such projects:

dependencies {
    // ...
    implementation "io.ktor:ktor-client:$ktor_version"
}

Samples

There is a full sample using the common client in the ktor-samples repository:

You can use this project as reference. This project also expose some experimental gradle tasks to build, install and run the Android and iOS applications directly from gradle.

Android:

  • :client-mpp-android:emulatorList - lists all the available emulators
  • :client-mpp-android:emulatorStart - starts the emulator (this would block gradle for now, so better to do in a separate terminal)
  • :client-mpp-android:emulatorInstall - install the application inside the emulator
  • :client-mpp-android:emulatorRun - executes the application inside the emulator

iOS:

  • :client-mpp-ios:startSimulator - starts the simulator
  • :client-mpp-ios:shutdownSimulator - shutdowns the simulator
  • :client-mpp-ios:buildXcode - builds the XCode project that uses the .framework from Kotlin/Native
  • :client-mpp-ios:installSimulator - installs the application inside the simulator
  • :client-mpp-ios:launchSimulator - executes the application inside the simulator

Since those tasks are experimental, might fail with your specific setup. Please let us know so we can improve them. Or help us with the iOS tasks, and the Android ones