1. Cobra简介
Cobra是一个cli接口模式的应用程序框架，同时也是生成该框架的命令行工具。用户可以通过help方式快速查看该二进制的使用方式。
Cobra主要包括以下部分
Command:一般表示action，即运行的二进制命令服务。同时可以拥有子命令（children commands）。Args:命令执行相关参数。Flags:二进制命令的配置参数，可对应配置文件。参数可分为全局参数和子命令参数。参考：pflag library。
2. 安装
通过以下操作可以在$GOPATH/bin安装cobra的二进制命令。
go get -u github.com/spf13/cobra/cobra
3. 使用
cobra命令行帮助信息如下：
# cobra
Cobra is a CLI library for Go that empowers applications.
This application is a tool to generate the needed files
to quickly create a Cobra application.
Usage:
cobra [command]
Available Commands:
add Add a command to a Cobra Application
help Help about any command
init Initialize a Cobra Application
Flags:
-a, --author string author name for copyright attribution (default "YOUR NAME")
--config string config file (default is $HOME/.cobra.yaml)
-h, --help help for cobra
-l, --license string name of license for the project
--viper use Viper for configuration (default true)
Use "cobra [command] --help" for more information about a command.
3.1. cobra init
# cobra init --help
Initialize (cobra init) will create a new application, with a license
and the appropriate structure for a Cobra-based CLI application.
* If a name is provided, it will be created in the current directory;
* If no name is provided, the current directory will be assumed;
* If a relative path is provided, it will be created inside $GOPATH
(e.g. github.com/spf13/hugo);
* If an absolute path is provided, it will be created;
* If the directory already exists but is empty, it will be used.
Init will not use an existing directory with contents.
Usage:
cobra init [name] [flags]
Aliases:
init, initialize, initialise, create
Flags:
-h, --help help for init
--pkg-name string fully qualified pkg name
Global Flags:
-a, --author string author name for copyright attribution (default "YOUR NAME")
--config string config file (default is $HOME/.cobra.yaml)
-l, --license string name of license for the project
--viper use Viper for configuration (default true)
3.2. cobra add
# cobra add --help
Add (cobra add) will create a new command, with a license and
the appropriate structure for a Cobra-based CLI application,
and register it to its parent (default rootCmd).
If you want your command to be public, pass in the command name
with an initial uppercase letter.
Example: cobra add server -> resulting in a new cmd/server.go
Usage:
cobra add [command name] [flags]
Aliases:
add, command
Flags:
-h, --help help for add
-p, --parent string variable name of parent command for this command (default "rootCmd")
Global Flags:
-a, --author string author name for copyright attribution (default "YOUR NAME")
--config string config file (default is $HOME/.cobra.yaml)
-l, --license string name of license for the project
--viper use Viper for configuration (default true)
参考：