Fix maas bridge-utils installation

utils/apt.go

 // Copyright 2012, 2013 Canonical Ltd.
 // Licensed under the AGPLv3, see LICENCE file for details.
 
 package utils
 
 import (
         "bytes"
         "fmt"
         "os"
         "os/exec"
@@ skipping 63 matching lines @@
 // that is suitable for use with the apt-get --target-release option
 func targetRelease(series string) string {
         switch series {
         case "precise":
                 return "precise-updates/cloud-tools"
         default:
                 return ""
         }
 }
 
+// AptGetCommand returns a command to execute apt-get
+// with the specified arguments, and the appropriate
+// environment variables and options for a non-interactive
+// session.
+func AptGetCommand(args ...string) []string {

[wwitzel3, 2014/03/20 10:02:29]

I have no complaint about the composition of this function, just than we are
using it to perform an apt-get install, when we have a func AptGetInstall.

At the least I feel like any of the existing Apt functions should use this under
the covers.

This also kind of ties back to if we can refactor the ComposeUserData to call
SetAptUpdate for the cloudinit. We could then use AptGetInstall for the package
install and this function could go away entirely.

+        cmd := append([]string{"env"}, aptGetEnvOptions...)
+        cmd = append(cmd, aptGetCommand...)
+        return append(cmd, args...)
+}
+
 // AptGetPreparePackages returns a slice of installCommands. Each item
 // in the slice is suitable for passing directly to AptGetInstall.
 //
 // AptGetPreparePackages will inspect the series passed to it
 // and properly generate an installCommand entry with a --target-release
 // should the series be an LTS release with cloud archive packages.
 func AptGetPreparePackages(packages []string, series string) [][]string {
         var installCommands [][]string
         if target := targetRelease(series); target == "" {
                 return append(installCommands, packages)
@@ skipping 106 matching lines @@
         }
         return strings.TrimSpace(out) == "Ubuntu"
 }
 
 // IsPackageInstalled uses dpkg-query to determine if the `packageName`
 // package is installed.
 func IsPackageInstalled(packageName string) bool {
         _, err := RunCommand("dpkg-query", "--status", packageName)
         return err == nil
 }