Cordova CLI源码分析（六）——添加插件
添加插件源码位于src/plugin.js 不再详细分析，主要用到plugman，也是Cordova 提供的用于安装和卸载插件的工具，见https://npmjs.org/package/plugman
主要内容摘录如下：
1环境：需要git工具支持
2 命令行使用
plugman install --platform <ios|android|blackberry10|wp7|wp8> --project <directory> --plugin <name|url|path> [--plugins_dir <directory>] [--www <directory>] [--variable <name>=<value> [--variable <name>=<value> ...]] plugman uninstall --platform <ios|android|blackberr10|wp7|wp8> --project <directory> --plugin <id> [--www <directory>] [--plugins_dir <directory>]
· Using minimum parameters, installs a plugin into a cordova project. You must specify a platform and cordova project location for that platform. You also must specify a plugin, with the different --plugin parameter forms being:
o name: The directory name where the plugin contents exist. This must be an existing directory under the --plugins_dir path (see below for more info) or a plugin in the Cordova registry.
o url: A URL starting with https:// or git://, pointing to a valid git repository that is clonable and contains a plugin.xml file. The contents of this repository would be copied into the --plugins_dir.
o path: A path to a directory containing a valid plugin which includes a plugin.xml file. This path's contents will be copied into the --plugins_dir.
· --uninstall: Uninstalls an already---install'ed plugin from a cordova project. Specify the plugin ID.
Other parameters:
· --plugins_dir defaults to <project>/cordova/plugins, but can be any directory containing a subdirectory for each fetched plugin.
· --www defaults to the project's www folder location, but can be any directory that is to be used as cordova project application web assets.
· --variable allows to specify certain variables at install time, necessary for certain plugins requiring API keys or other custom, user-defined parameters. Please see the plugin specificationfor more information.
3 源码中API接口
（1）install method
module.exports = function installPlugin(platform, project_dir, id, plugins_dir, subdir, cli_variables, www_dir, callback) {
Installs a plugin into a specified cordova project of a specified platform.
· platform: one of android, ios, blackberry10, wp7 or wp8
· project_dir: path to an instance of the above specified platform's cordova project
· id: a string representing the id of the plugin, a path to a cordova plugin with a validplugin.xml file, or an https:// or git:// url to a git repository of a valid cordova plugin or a plugin published to the Cordova registry
· plugins_dir: path to directory where plugins will be stored, defaults to<project_dir>/cordova/plugins
· subdir: subdirectory within the plugin directory to consider as plugin directory root, defaults to .
· cli_variables: an object mapping cordova plugin specification variable namess (see plugin specification) to values
· www_dir: path to directory where web assets are to be copied to, defaults to the specified project directory's www dir (dependent on platform)
callback: callback to invoke once complete. If specified, will pass in an error object as a first parameter if the action failed. If not and an error occurs, plugman will throw the error
（2）uninstall method
module.exports = function uninstallPlugin(platform, project_dir, id, plugins_dir, cli_variables, www_dir, callback) {
Uninstalls a previously-installed cordova plugin from a specified cordova project of a specified platform.
· platform: one of android, ios, blackberry10, wp7 or wp8
· project_dir: path to an instance of the above specified platform's cordova project
· id: a string representing the id of the plugin
· plugins_dir: path to directory where plugins are stored, defaults to<project_dir>/cordova/plugins
· subdir: subdirectory within the plugin directory to consider as plugin directory root, defaults to .
· cli_variables: an object mapping cordova plugin specification variable namess (see plugin specification) to values
· www_dir: path to directory where web assets are to be copied to, defaults to the specified project directory's www dir (dependent on platform)
· callback: callback to invoke once complete. If specified, will pass in an error object as a first parameter if the action failed. If not and an error occurs, plugman will throw the error
（3）fetch method
Copies a cordova plugin into a single location that plugman uses to track which plugins are installed into a project.
module.exports = function fetchPlugin(plugin_dir, plugins_dir, link, subdir, git_ref, callback) {
· plugin_dir: path, URL to a plugin directory/repository or name of a plugin published to the Cordova registry.
· plugins_dir: path housing all plugins used in this project
· link: if plugin_dir points to a local path, will create a symbolic link to that folder instead of copying into plugins_dir, defaults to false
· subdir: subdirectory within the plugin directory to consider as plugin directory root, defaults to .
· gitref: if plugin_dir points to a URL, this value will be used to pass into git checkout after the repository is cloned, defaults to HEAD
· callback: callback to invoke once complete. If specified, will pass in an error object as a first parameter if the action failed. If not and an error occurs, plugman will throw the error
（4）prepare method
Finalizes plugin installation by making configuration file changes and setting up a JavaScript loader for js-module support.
module.exports = function handlePrepare(project_dir, platform, plugins_dir) {
· project_dir: path to an instance of the above specified platform's cordova project
· platform: one of android, ios, blackberry10, wp7 or wp8
· plugins_dir: path housing all plugins used in this project
4 插件目录结构
foo-plugin/
|- plugin.xml # xml-based manifest
|- src/ # native source for each platform
| |- android/
| | `- Foo.java
| `- ios/
| |- CDVFoo.h
| `- CDVFoo.m
|- README.md
`- www/
|- foo.js
`- foo.png