Plugin Specification

The plugin.xml file is an XML document in the plugins namespace: http://apache.org/cordova/ns/plugins/1.0. It contains a top-level plugin element that defines the plugin, and children that define the structure of the plugin.

A sample plugin element:

<?xml version="1.0" encoding="UTF-8"?>
<plugin xmlns="http://apache.org/cordova/ns/plugins/1.0"
    xmlns:android="http://schemas.android.com/apk/res/android"
    id="com.alunny.foo"
    version="1.0.2">

<plugin> element

The plugin element is the plugin manifest's top-level element. It features the following attributes:

  • xmlns (required): The plugin namespace, http://apache.org/cordova/ns/plugins/1.0. If the document contains XML from other namespaces, such as tags to be added to the AndroidManifest.xml file, those namespaces should also be included in the top-level element.

  • id (required): A reverse-domain style identifier for the plugin, such as com.alunny.foo

  • version (required): A version number for the plugin, that matches the following major-minor-patch style regular expression:

    ^\d+[.]\d+[.]\d+$
    

<engines> and <engine> elements

The child elements of the <engines> element specify versions of Apache Cordova-based frameworks that this plugin supports. An example:

<engines>
    <engine name="cordova" version="1.7.0" />
    <engine name="cordova" version="1.8.1" />
    <engine name="worklight" version="1.0.0" />
</engines>

Similar to the <plugin> element's version attribute, the specified version string should match a major-minor-patch string conforming to the regular expression:

    ^\d+[.]\d+[.]\d+$

Engine elements may also specify fuzzy matches to avoid repetition, and to reduce maintenance when the underlying platform is updated. Tools should support a minimum of >, >=, < and <=, for example:

<engines>
    <engine name="cordova" version=">=1.7.0" />
    <engine name="cordova" version="<1.8.1" />
</engines>

plugman aborts with a non-zero code for any plugin whose target project does not meet the engine's constraints.

If no <engine> tags are specified, plugman attempts to install into the specified cordova project directory blindly.

<name> element

A human-readable name for the plugin, whose text content contains the name of the plugin. For example:

<name>Foo</name>

This element does not (yet) handle localization.

<description> element

A human-readable description for the plugin. The text content of the element contains the description of the plugin. An example:

<description>Foo plugin description</description>

This element does not (yet) handle localization.

<author> element

Plugin author name. The text content of the element contains the name of the plugin author. An example:

<author>Foo plugin description</author>

<keywords> element

Plugin keywords. The text content of the element contains comma separated keywords to describe the plugin. An example:

<keywords>foo,bar</keywords>

<license> element

Plugin license. The text content of the element contains the plugin license. An example:

<license>Apache 2.0 License</license>

<asset> element

One or more elements listing the files or directories to be copied into a Cordova app's www directory. Examples:

<!-- a single file, to be copied in the root directory -->
<asset src="www/foo.js" target="foo.js" />
<!-- a directory, also to be copied in the root directory -->
<asset src="www/foo" target="foo" />

All <asset> tags require both src and target attributes. Web-only plugins contains mostly <asset> elements. Any <asset> elements that are nested within <platform> elements specify platform-specific web assets, as described below. Attributes include:

  • src (required): Where the file or directory is located in the plugin package, relative to the plugin.xml document. If a file does not exist at the specified src location, plugman stops and reverses the installation process, issues a notification about the conflict, and exits with a non-zero code.

  • target (required):

Where the file or directory should be located in the Cordova app, relative to the www directory. Assets can be targeted to subdirectories, for example:

<asset src="www/new-foo.js" target="js/experimental/foo.js" />

creates the js/experimental directory within the www directory, unless already present, then copies the new-foo.js file and renames it foo.js. If a file already exists at the target location, plugman stops and reverses the installation process, issues a notification about the conflict, and exits with a non-zero code.

<js-module> element

Most plugins include one or more JavaScript files. Each <js-module> tag corresponds to a JavaScript file, and prevents the plugin's users from having to add a <script> tag for each file. While <asset> tags simply copy a file from the plugin subdirectory into www, <js-module> tags are much more sophisticated. They look like this:

<js-module src="socket.js" name="Socket">
    <clobbers target="chrome.socket" />
</js-module>

When installing a plugin with the example above, socket.js is copied to www/plugins/my.plugin.id/socket.js, and added as an entry to www/cordova_plugins.js. At load time, code in cordova.js uses XHR to read each file and inject a <script> tag into HTML. It adds a mapping to clobber or merge as appropriate, as described below.

Do not wrap the file with cordova.define, as it is added automatically. The module is wrapped in a closure, with module, exports, and require in scope, as is normal for AMD modules.

Details for the <js-module> tag:

  • The src references a file in the plugin directory relative to the plugin.xml file.

  • The name provides the last part of the module name. It can generally be whatever you like, and it only matters if you want to use cordova.require to import other parts of your plugins in your JavaScript code. The module name for a <js-module> is your plugin's id followed by the value of name. For the example above, with an id of chrome.socket, the module name is chrome.socket.Socket.

  • Three tags are allowed within <js-module>:

    • <clobbers target="some.value"/> indicates that the module.exports is inserted into the window object as window.some.value. You can have as many <clobbers> as you like. Any object not available on window is created.
    • <merges target="some.value"/> indicates that the module should be merged with any existing value at window.some.value. If any key already exists, the module's version overrides the original. You can have as many <merges> as you like. Any object not available on window is created.
    • <runs/> means that your code should be specified with cordova.require, but not installed on the window object. This is useful when initializing the module, attaching event handlers or otherwise. You can only have up to one <runs/> tag. Note that including a <runs/> with <clobbers/> or <merges/> is redundant, since they also cordova.require your module.
    • An empty <js-module> still loads and can be acccessed in other modules via cordova.require.

If src does not resolve to an existing file, plugman stops and reverses the installation, issues a notification of the problem, and exits with a non-zero code.

Nesting <js-module> elements within <platform> declares platform-specific JavaScript module bindings.

<dependency>

The <dependency> tag allows you specify other plugins on which the current plugin depends. While future versions will access them from plugin repositories, in the short term plugins are directly referenced as URLs by <dependency> tags. They are formatted as follows:

<dependency id="com.plugin.id" url="https://github.com/myuser/someplugin" commit="428931ada3891801" subdir="some/path/here" />
  • id: provides the ID of the plugin. It should be globally unique, and expressed in reverse-domain style. While neither of these restrictions is currently enforced, they may be in the future.

  • url: A URL for the plugin. This should reference a git repository, which plugman attempts to clone.

  • commit: This is any git reference understood by git checkout: a branch or tag name (e.g., master, 0.3.1), or a commit hash (e.g., 975ddb228af811dd8bb37ed1dfd092a3d05295f9).

  • subdir: Specifies that the targeted plugin dependency exists as a subdirectory of the git repository. This is helpful because it allows the repository to contain several related plugins, each specified individually.

In the future, version constraints will be introduced, and a plugin repository will exist to support fetching by name instead of explicit URLs.

Relative Dependency Paths

If you set the url of a <dependency> tag to "." and provide a subdir, the dependent plugin is installed from the same local or remote git repository as the parent plugin that specifies the <dependency> tag.

Note that the subdir always specifies a path relative to the root of the git repository, not the parent plugin. This is true even if you installed the plugin with a local path directly to it. Plugman finds the root of the git repository and then finds the other plugin from there.

<platform>

The <platform> tag identifies platforms that have associated native code or require modifications to their configuration files. Tools using this specification can identify supported platforms and install the code into Cordova projects.

Plugins without <platform> tags are assumed to be JavaScript-only, and therefore installable on any and all platforms.

A sample platform tag:

<platform name="android">
    <!-- android-specific elements -->
</platform>
<platform name="ios">
    <!-- ios-specific elements -->
</platform>

The required name attribute identifies a platform as supported, associating the element's children with that platform.

Platform names should be lowercase. Platform names, as arbitrarily chosen, are listed:

  • android
  • bb10
  • ios
  • wp7
  • wp8

<source-file>

The <source-file> element identifies executable source code that should be installed into a project. Examples:

<!-- android -->
<source-file src="src/android/Foo.java"
                target-dir="src/com/alunny/foo" />
<!-- ios -->
<source-file src="src/ios/CDVFoo.m" />
<source-file src="src/ios/someLib.a" framework="true" />
<source-file src="src/ios/someLib.a" compiler-flags="-fno-objc-arc" />

It supports the following attributes:

  • src (required): Location of the file relative to plugin.xml. If the src file cannot be found, plugman stops and reverses the installation, issues a notification about the problem, and exits with a non-zero code.

  • target-dir: A directory into which the files should be copied, relative to the root of the Cordova project. In practice, this is most important for Java-based platforms, where a file in the com.alunny.foo package must be located within the com/alunny/foo directory. For platforms where the source directory is not important, this attribute should be omitted.

As with assets, if the target of a source-file would overwrite an existing file, plugman stops and reverses the installation, issues a notification about the problem, and exits with a non-zero code.

  • framework (iOS only): If set to true, also adds the specified file as a framework to the project.

  • compiler-flags (iOS only): If set, assigns the specified compiler flags for the particular source file.

<config-file>

Identifies an XML-based configuration file to be modified, where in that document the modification should take place, and what should be modified.

Two file types that have been tested for modification with this element are xml and plist files.

The config-file element only allows you to append new children to an XML document tree. The children are XML literals to be inserted in the target document.

Example for XML:

<config-file target="AndroidManifest.xml" parent="/manifest/application">
    <activity android:name="com.foo.Foo" android:label="@string/app_name">
        <intent-filter>
        </intent-filter>
    </activity>
</config-file>

Example for plist:

<config-file target="*-Info.plist" parent="CFBundleURLTypes">
    <array>
        <dict>
            <key>PackageName</key>
            <string>$PACKAGE_NAME</string>
        </dict>
    </array>
</config-file>

It supports the following attributes:

  • target:

The file to be modified, and the path relative to the root of the Cordova project.

The target can include wildcard (*) elements. In this case, plugman recursively searches through the project directory structure and uses the first match.

On iOS, the location of configuration files relative to the project directory root is not known, so specifying a target of config.xml resolves to cordova-ios-project/MyAppName/config.xml.

If the specified file does not exist, the tool ignores the configuration change and continues installation.

  • parent: An XPath selector referencing the parent of the elements to be added to the config file. If you use absolute selectors, you can use a wildcard (*) to specify the root element, e.g., /*/plugins.

For plist files, the parent determines under what parent key the specified XML should be inserted.

If the selector does not resolve to a child of the specified document, the tool stops and reverses the installation process, issues a warning, and exits with a non-zero code.

<plugins-plist>

This is outdated as it only applies to cordova-ios 2.2.0 and below. Use the <config-file> tag for newer versions of Cordova.

Example:

<config-file target="config.xml" parent="/widget/plugins">
    <feature name="ChildBrowser">
        <param name="ios-package" value="ChildBrowserCommand"/>
    </feature>
</config-file>

Specifies a key and value to append to the correct AppInfo.plist file in an iOS Cordova project. For example:

<plugins-plist key="Foo" string="CDVFoo" />

<resource-file> and <header-file>

Like source files, but specifically for platforms such as iOS that distinguish between source files, headers, and resources. Examples:

<resource-file src="CDVFoo.bundle" />
<resource-file src="CDVFooViewController.xib" />
<header-file src="CDVFoo.h" />

<lib-file>

Like source, resource, and header files, but specifically for platforms such as BlackBerry 10 that use user-generated libraries. Examples:

<lib-file src="src/BlackBerry10/native/device/libfoo.so" arch="device" />
<lib-file src="src/BlackBerry10/native/simulator/libfoo.so" arch="simulator" />

Supported attributes:

  • src (required): The location of the file relative to plugin.xml. If src cannot be found, plugman stops and reverses the installation, issues a warning about the problem, and exits with a non-zero code.

  • arch: The architecture for which the .so file has been built, either device or simulator.

<framework>

Identifies a framework (usually part of the OS/platform) on which the plugin depends.

Examples:

<framework src="libsqlite3.dylib" />
<framework src="social.framework" weak="true" />

The src attribute identifies the framework, which plugman attempts to add to the Cordova project, in the correct fashion for a given platform.

The optional weak attribute is a boolean indicating whether the framework should be weakly linked. The default is false.

<info>

Additional information provided to users. This is useful when you require extra steps that can't be easily automated or are beyond plugman's scope. Examples:

<info>
You need to install __Google Play Services__ from the `Android Extras` section using the Android SDK manager (run `android`).

You need to add the following line to your `local.properties`

android.library.reference.1=PATH_TO_ANDROID_SDK/sdk/extras/google/google_play_services/libproject/google-play-services_lib
</info>

Variables

In certain cases, a plugin may need to make configuration changes dependent on the target application. For example, to register for C2DM on Android, an app whose package id is com.alunny.message would require a permission such as:

<uses-permission
android:name="com.alunny.message.permission.C2D_MESSAGE"/>

In such cases where the content inserted from the plugin.xml file is not known ahead of time, variables can be indicated by a dollar-sign followed by a series of capital letters, digits, or underscores. For the above example, the plugin.xml file would include this tag:

<uses-permission
android:name="$PACKAGE_NAME.permission.C2D_MESSAGE"/>

plugman replaces variable references with the specified value, or the empty string if not found. The value of the variable reference may be detected (in this case, from the AndroidManifest.xml file) or specified by the user of the tool; the exact process is dependent on the particular tool.

plugman can request users to specify a plugin's required variables. For example, API keys for C2M and Google Maps can be specified as a command-line argument:

plugman --platform android --project /path/to/project --plugin name|git-url|path --variable API_KEY=!@CFATGWE%^WGSFDGSDFW$%^#$%YTHGsdfhsfhyer56734

To make the variable mandatory, the <platform> tag needs to contain a <preference> tag. For example:

<preference name="API_KEY" />

plugman checks that these required preferences are passed in. If not, it should warn the user how to pass the variable in and exit with a non-zero code.

Certain variable names should be reserved, as listed below.

$PACKAGE_NAME

The reverse-domain style unique identifier for the package, corresponding to the CFBundleIdentifier on iOS or the package attribute of the top-level manifest element in an AndroidManifest.xml file.