environ.StateInfo() for Azure provider.

environs/maas/state.go

 // Copyright 2013 Canonical Ltd.
 // Licensed under the AGPLv3, see LICENCE file for details.
 
 package maas
 
 import (
         "bytes"
         "fmt"
         "io/ioutil"
         "launchpad.net/goyaml"
         "launchpad.net/juju-core/instance"
 )
+
+// TODO: This entire file is duplicated between the EC2, OpenStack, MAAS,
+// and Azure providers (bug 1195721).
 
 const stateFile = "provider-state"
 
 // Persistent environment state.  An environment needs to know what instances
 // it manages.
 type bootstrapState struct {
         StateInstances []instance.Id `yaml:"state-instances"`
 }
 
 // saveState writes the environment's state to the provider-state file stored
@@ skipping 18 matching lines @@
         if err != nil {
                 return nil, fmt.Errorf("error reading %q: %v", stateFile, err)
         }
         var state bootstrapState
         err = goyaml.Unmarshal(data, &state)
         if err != nil {
                 return nil, fmt.Errorf("error unmarshalling %q: %v", stateFile, err)
         }
         return &state, nil
 }