cmd/juju: working bootstrap and destroy commands

cmd/jujud/unit.go

 package main
 
 import (
         "fmt"
         "launchpad.net/gnuflag"
+        "launchpad.net/juju/go/cmd"
         "launchpad.net/juju/go/juju"
 )
 
 // UnitAgent is a cmd.Command responsible for running a unit agent.
 type UnitAgent struct {
         agentConf
         UnitName string
 }
 
 func NewUnitAgent() *UnitAgent {
         return &UnitAgent{agentConf: agentConf{name: "unit"}}
 }
 
-// InitFlagSet prepares a FlagSet.
-func (a *UnitAgent) InitFlagSet(f *gnuflag.FlagSet) {
+// Init initializes the command for running.
+func (a *UnitAgent) Init(f *gnuflag.FlagSet, args []string) error {
         f.StringVar(&a.UnitName, "unit-name", "", "name of the unit to run")
-        a.agentConf.InitFlagSet(f)
-}
-
-// ParsePositional checks that there are no unwanted arguments, and that all
-// required flags have been set.
-func (a *UnitAgent) ParsePositional(args []string) error {
+        if err := a.agentConf.Init(f, args); err != nil {
+                return err
+        }
         if a.UnitName == "" {
                 return requiredError("unit-name")
         }
         if !juju.ValidUnit.MatchString(a.UnitName) {
                 return fmt.Errorf(`--unit-name option expects "<service>/<n>" argument`)
         }
-        return a.agentConf.ParsePositional(args)
+        return nil
 }
 
 // Run runs a unit agent.
-func (a *UnitAgent) Run() error {
+func (a *UnitAgent) Run(_ *cmd.Context) error {
         return fmt.Errorf("UnitAgent.Run not implemented")
 }