What Are NativeScript Plugins

A NativeScript plugin is any npm package, published or not, that exposes a native API via JavaScript and consists of the following elements.

A package.json file which contains the following metadata: name, version, supported runtime versions, dependencies and others. For more information, see the package.json Specification section.
One or more CommonJS modules that expose a native API via a unified JavaScript API. For more information about Common JS modules, see the CommonJS Wiki.
(Optional) Descriptions of permissions, features or other configurations required or used by your plugin inside a pre-compiled Android native library containing an AndroidManifest.xml or an Info.plist file for Android and iOS, respectively. For more information about Android native libraries, see the Android permissions and resources section.
(Optional) Native Android libraries and the native Android include.gradle configuration file which describes the native dependencies. For more information, see the include.gradle Specification section.
(Optional) Native iOS libraries and the native build.xcconfig configuration file which describes the native dependencies. For more information, see the build.xcconfig Specification section.

The plugin must have the directory structure, described in the Directory Structure section.

Create a Plugin

If the NativeScript framework does not expose a native API that you need, you can develop a plugin which exposes the required functionality. When you develop a NativeScript plugin, keep in mind the following requirements.

The plugin must be a valid npm package.
The plugin must expose a built-in native API or a native API available via custom native libraries.
The plugin must be written in JavaScript and must comply with the CommonJS specification. If you are using a transpiler (e.g. from TypeScript), make sure to include the transpiled JavaScript files in your plugin.
The plugin name should be postfixed with nativescript, tns, or the ns keywords (e.g., like nativescript-camera or tns-core-modules).
The plugin directory structure must comply with the specification described below.
The plugin must contain a valid package.json which complies with the specification described below.
If the plugin requires any permissions, features or other configuration specifics, it must contain an Info.plist for iOS or a compiled library with an AndroidManifest.xml file for Android which describe them. For more information about Android native libraries, see the Android permissions and resources section.
If the plugin depends on other native libraries, it must contain a valid include.gradle or build.xcconfig file, which describes the dependencies.

Directory Structure

NativeScript plugins which consist of one CommonJS module might have the following directory structure.

nativescript-my-plugin/
└── src
    ├── index.js
    ├── package.json
    └── platforms/
        ├── android/
        │   └── nativescript-my-plugin.aar (containing custom resources or permissions)
        └── ios/
            └── Info.plist

NativeScript plugins which consist of multiple CommonJS modules might have the following directory structure.

nativescript-my-plugin/
└── src
    ├── index.js
    ├── package.json
    ├── MyModule1/
    │   ├── index1.js
    │   └── package.json
    ├── MyModule2/
    │   ├── index2.js
    │   └── package.json
    └── platforms/
        ├── android/
        │   └── nativescript-my-plugin.aar (containing custom resources or permissions)
        └── ios/
            └── Info.plist

src: Putting your source in sub-folder is required for local LiveSync debugging. Older plugins should be updated to move their source code in to a subfolder.
index.js: This file is the CommonJS module which exposes the native API. You can use platform-specific *.[platform].js files. For example: index.ios.js and index.android.js. During the plugin installation, the NativeScript CLI will copy the platform resources to the tns_modules subdirectory in the correct platform destination in the platforms directory of your project.
Alternatively, you can give any name to this CommonJS module. In this case, however, you need to point to this file by setting the main key in the package.json for the plugin. For more information, see Folders as Modules.
package.json: This file contains the metadata for your plugin. It sets the supported runtimes, the plugin name and version and any dependencies. The package.json specification is described in detail below.
platforms/android/native-library.aar Compiled native libraries (*.aar files) contain resources, code and any specific configuration changes, like permissions, required for your plugin to work. For more information about Android native libraries, see the Android permissions and resources section.
platforms\ios\Info.plist: This file describes any specific configuration changes required for your plugin to work. For example, required permissions. To your convenience, all configurations that are applicable via XCode Info tab and are saved in application's Info.plist file can also be applied manually for plugins directly in the Info.plist. For more information about the format of Info.plist, see About Information Property List Files.
During the plugin installation, the NativeScript CLI will merge the plugin Info.plist with the Info.plist for your project. The NativeScript CLI will not resolve any contradicting or duplicate entries during the merge. After the plugin is installed, you need to manually resolve such issues.

NativeScript plugins which contain both native Android and iOS libraries might have the following directory structure.

nativescript-my-plugin/
└── src
    ├── ...
    └── platforms/
        ├── android/
        │   ├── MyLibraryOne.jar
        │   ├── MyLibraryTwo.aar
        │   ├── include.gradle
        └── ios/
            ├── MyiOSFramework.framework
            ├── build.xcconfig
            ├── Podfile
            ├── Info.plist
            ├── MyStaticiOSLibrary.a
            └── include/
                └── MyStaticiOSLibrary/
                    └── ...

platforms\android: This directory contains any native Android libraries packaged as *.jar and *.aar packages. These native libraries can reside in the root of this directory or in a user-created sub-directory. During the plugin installation, the NativeScript CLI will configure the Android project in platforms\android to work with the plugin.
platforms\android\include.gradle: This file modifies the native Android configuration of your NativeScript project such as native dependencies, build types and configurations. For more information about the format of include.gradle, see include.gradle file.
platforms\ios: This directory contains native dynamic iOS Cocoa Touch Frameworks (.framework) and Cocoa Touch Static Libraries (.a). During the plugin installation, the NativeScript CLI will copy these files to lib\iOS in your project and will configure the iOS project in platforms\ios to work with the libraries. If the library is written in Swift, only APIs exposed to Objective-C are exposed to NativeScript. In case the plugin contains a Cocoa Touch Static Library (.a), you must place all public headers (.h) under include\<Static Library Name>\. Make sure that the static libraries are built at least for the following processor architectures - armv7, arm64, i386.
platforms\ios\build.xcconfig: This file modifies the native iOS configuration of your NativeScript project such as native dependencies and configurations. For more information about the format of build.xcconfig, see build.xcconfig file.
platforms\ios\Podfile: This file describes the dependency to the library that you want to use. For more information, see the CocoaPods article.

Package.json Specification

Every NativeScript plugin should contain a valid package.json file in its root. This package.json file must meet the following requirements.

It must comply with the npm specification.
The package.json must contain at least name and version pairs. You will later use the plugin in your code by requiring it by its name.
It must contain a nativescript section which describes the supported NativeScript runtimes and their versions. This section can be empty. If you want to define supported platforms and runtimes, you can nest a platforms section. In this platforms section, you can nest ios and android key-value pairs. The values in these pairs must be valid runtime versions or ranges of values specified by a valid semver(7) syntax.
If the plugin depends on other npm modules, it must contain a dependencies section as described here.
The NativeScript CLI will resolve the dependencies during the plugin installation.

The following is an example of a package.json file for a NativeScript plugin which supports the 1.0.0 version or above of the iOS runtime and the 1.1.0 version or above of the Android runtime.

{
  "name": "nativescript-my-plugin",
  "version": "0.0.1",
  "nativescript": {
    "platforms": {
      "ios": "4.0.0",
      "android": "4.1.0"
    }
  }
}

The above configuration states that the plugin requires iOS runtime version 4.0.0 and up or Android runtime version 4.1.0 and up.

Note In case your plugin supports only iOS or Android, make sure to remove the platform which is not supported.

Include.gradle Specification

Every NativeScript plugin, which contains native Android dependencies, should also contain a valid include.gradle file in the root of its platforms\android directory. This include.gradle file must meet the following requirements.

It must contain its own configuration.
It might contain native dependencies required to build the plugin properly.
Any native dependencies should be available in jcenter or from the Android SDK installed on your machine.

IMPORTANT: If you don't have an include.gradle file, at build time, gradle will create a default one containing all default elements.

Include.gradle Example

//default elements
android {
  productFlavors {
    "nativescript-my-plugin" {
      dimension "nativescript-my-plugin"
    }
  }
}

//optional elements
dependencies {
    implementation "groupName:pluginName:ver"
}

Android permissions and resources

There are two ways to add permissions and resources for your plugin.

Using a native Android project

If you want your plugin to use special permissions, have custom resources or just want to write some native Java code to be accessed later from the JavaScript/Typescript implementation, you should create a native Android project for your plugin, compile it to an .aar file and put it in the src/platforms/android directory of the plugin package. The easiest way to do this is using Android Studio. The project can contain the following files:

project/src/main/AndroidManifest.xml: This file describes any specific configuration changes required for your plugin to work. For example: required permissions. For more information about the format of AndroidManifest.xml, see App Manifest.
project/src/main/res: (Optional) This directory contains resources declared by the AndroidManifest.xml file. You can look at its structure here.
project/src/main/java: (Optional) This directory contains Java code sources.

For a more complete Android library project overview visit the Android Documentation.

Using the NativeScript CLI plugin complier

In previous versions of the the NativeScript CLI it was possible to add permissions and resources for Android without a separate native library (.aar file). If you have an older plugin and your AndroidManifest.xml file and res directory are located in platforms/android, then you can compile them with a CLI command. Open a terminal, go to the src directory of the plugin and execute:

tns plugin build

This will create an .aar file in the platforms/android directory, which will contain the compiled manifest and resources and should be included in the plugin package instead of them. If you keep AndroidManifest.xml and res resources in your package, the NativeScript will internally run the tns plugin build command when it builds the native application, which will slow down the process for all users of your plugin. This is why the recommended approach is to have an .aar library in the platforms/android directory of the plugin package instead of plain manifest xml and resource files.

Build.xcconfig Specification

Every NativeScript plugin, which contains native iOS dependencies, can also contain a valid build.xcconfig file in the root of its platforms\ios directory. This build.xcconfig file might contain native dependencies required to build the plugin properly.

Build.xcconfig Example

OTHER_LDFLAGS = $(inherited) -framework "QuartzCore" -l"sqlite3"

Metadata filtering usage specifications

Application author can opt-in for native metadata filtering. Plugins should supply their metadata filtering rules in platforms/android/native-api-usage.json and platforms/ios/native-api-usage.json files respectively. For more detailed description of this feature read this article

Install a Plugin

To install a plugin for your project, inside your project, run the following command.

tns plugin add <Plugin>

Valid Plugin Sources

You can specify a plugin by name in the npm registry, local path or URL. The following are valid values for the <Plugin> attribute.

A <Name> or <Name>@<Version> for plugins published in the npm registry.
A <Local Path> to the directory which contains the plugin source files and its package.json file.
A <Local Path> to a .tar.gz archive containing a directory with the plugin and its package.json file.
A <URL> which resolves to a .tar.gz archive containing a directory with the plugin and its package.json file.
A <git Remote URL> which resolves to a .tar.gz archive containing a directory with the plugin and its package.json file.

Installation Specifics

The installation of a NativeScript plugin mimics the installation of an npm module.

The NativeScript CLI takes the plugin and installs it to the node_modules directory in the root of your project. During this process, the NativeScript CLI resolves any dependencies described in the plugin package.json file and adds the plugin to the project package.json file in the project root.

If the NativeScript CLI detects any native iOS libraries in the plugin, it copies the library files to the lib\ios folder in your project and configures the iOS-specific projects in platforms\ios to work with the library.

Next, the NativeScript CLI runs a partial prepare operation for the plugin for all platforms configured for the project. During this operation, the CLI copies only the plugin to the tns_modules subdirectories in the platforms\android and platforms\ios directories in your project. If your plugin contains platform-specific JS files, the CLI copies them to the respective platform subdirectory and renames them by removing the platform modifier.

TIP: If you have not configured any platforms, when you run $ tns platform add, the NativeScript CLI will automatically prepare all installed plugins for the newly added platform.

Finally, the CLI merges the plugin Info.plist file with platforms\ios\Info.plist in your project. The plugin AndroidManifest.xml will be merged with platforms\android\AndroidManifest.xml later, at build time.

IMPORTANT: Currently, the merging of the platform configuration files does not resolve any contradicting or duplicate entries.

Use a Plugin

To use a plugin inside your project, you need to add a require in your app.

var myPlugin = require("nativescript-my-plugin");

This will look for a nativescript-my-plugin module with a valid package.json file in the tns_modules directory. Note that you must require the plugin with the value for the name key in the plugin package.json file.

Remove a Plugin

To remove a plugin from your project, inside your project, run the following command.

tns plugin remove <Plugin>

You must specify the plugin by the value for the name key in the plugin package.json file.

Removal Specifics

The removal of a NativeScript plugin mimics the removal of an npm module.

The NativeScript CLI removes any plugin files from the node_modules directory in the root of your project. During this process, the NativeScript CLI removes any dependencies described in the plugin package.json file and removes the plugin from the project package.json file in the project root.

IMPORTANT: For iOS, this operation does not remove files from the platforms\ios directories and native iOS libraries, and does not unmerge the Info.plist file. For Android, this operation takes care of removing any plugin files located in platforms\android.

Manual Steps After Removal

After the plugin removal is complete, make sure to remove any leftover native iOS library files from the lib\ios directory in the root of the project. Update the iOS-specific projects in platforms\ios to remove any dependencies on the removed native libraries.

Next, you need to run the following command.

tns prepare <Platform>

Make sure to run the command for all platforms configured for the project. During this operation, the NativeScript CLI will remove any leftover plugin files from your platforms\ios directory.

TIP: Instead of $ tns prepare you can run $ tns build, $ tns run, $ tns deploy or $ tns emulate. All these commands run $ tns prepare.

Next, open your platforms\ios\Info.plist file and remove any leftover entries from the plugin Info.plist file.

Finally, make sure to update your code not to use the uninstalled plugin.

NativeScript Core

Using a native Android project

Using the NativeScript CLI plugin complier