packer-cn/packer/rpc/command.go

84 lines
1.7 KiB
Go

package rpc
import (
"github.com/mitchellh/packer/packer"
"net/rpc"
)
// A Command is an implementation of the packer.Command interface where the
// command is actually executed over an RPC connection.
type command struct {
client *rpc.Client
}
// A CommandServer wraps a packer.Command and makes it exportable as part
// of a Golang RPC server.
type CommandServer struct {
command packer.Command
}
type CommandRunArgs struct {
RPCAddress string
Args []string
}
type CommandSynopsisArgs byte
func Command(client *rpc.Client) *command {
return &command{client}
}
func (c *command) Help() (result string) {
err := c.client.Call("Command.Help", new(interface{}), &result)
if err != nil {
panic(err)
}
return
}
func (c *command) Run(env packer.Environment, args []string) (result int) {
// Create and start the server for the Environment
server := rpc.NewServer()
RegisterEnvironment(server, env)
rpcArgs := &CommandRunArgs{serveSingleConn(server), args}
err := c.client.Call("Command.Run", rpcArgs, &result)
if err != nil {
panic(err)
}
return
}
func (c *command) Synopsis() (result string) {
err := c.client.Call("Command.Synopsis", CommandSynopsisArgs(0), &result)
if err != nil {
panic(err)
}
return
}
func (c *CommandServer) Help(args *interface{}, reply *string) error {
*reply = c.command.Help()
return nil
}
func (c *CommandServer) Run(args *CommandRunArgs, reply *int) error {
client, err := rpc.Dial("tcp", args.RPCAddress)
if err != nil {
return err
}
env := &Environment{client}
*reply = c.command.Run(env, args.Args)
return nil
}
func (c *CommandServer) Synopsis(args *CommandSynopsisArgs, reply *string) error {
*reply = c.command.Synopsis()
return nil
}