15fb4c990a
This PR switches the Nomad repository from using govendor to Go modules for managing dependencies. Aspects of the Nomad workflow remain pretty much the same. The usual Makefile targets should continue to work as they always did. The API submodule simply defers to the parent Nomad version on the repository, keeping the semantics of API versioning that currently exists.
Go CLI Library 
cli is a library for implementing powerful command-line interfaces in Go. cli is the library that powers the CLI for Packer, Serf, Consul, Vault, Terraform, and Nomad.
Features
-
Easy sub-command based CLIs:
cli foo,cli bar, etc. -
Support for nested subcommands such as
cli foo bar. -
Optional support for default subcommands so
clidoes something other than error. -
Support for shell autocompletion of subcommands, flags, and arguments with callbacks in Go. You don't need to write any shell code.
-
Automatic help generation for listing subcommands
-
Automatic help flag recognition of
-h,--help, etc. -
Automatic version flag recognition of
-v,--version. -
Helpers for interacting with the terminal, such as outputting information, asking for input, etc. These are optional, you can always interact with the terminal however you choose.
-
Use of Go interfaces/types makes augmenting various parts of the library a piece of cake.
Example
Below is a simple example of creating and running a CLI
package main
import (
"log"
"os"
"github.com/mitchellh/cli"
)
func main() {
c := cli.NewCLI("app", "1.0.0")
c.Args = os.Args[1:]
c.Commands = map[string]cli.CommandFactory{
"foo": fooCommandFactory,
"bar": barCommandFactory,
}
exitStatus, err := c.Run()
if err != nil {
log.Println(err)
}
os.Exit(exitStatus)
}