Merge lp:~thumper/juju-core/instance-id into lp:~go-bot/juju-core/trunk

[Tim Penhey]

Move state.InstanceId to instance.Id

Very mechanical change, just imports, and occasional variable renames.

https://codereview.appspot.com/10325043/

Move state.InstanceId to instance.Id

Very mechanical change, just imports, and occasional variable renames.

https://codereview.appspot.com/10325043/

[Tim Penhey (thumper)]

Reviewers: mp+169709_code.launchpad.net,

Message:
Please take a look.

Description:
Move state.InstanceId to instance.Id

Very mechanical change, just imports, and occasional variable renames.

https://code.launchpad.net/~thumper/juju-core/instance-id/+merge/169709

Requires:
https://code.launchpad.net/~thumper/juju-core/lxc-cloud-init/+merge/169328

(do not edit description out of merge proposal)

Please review this at https://codereview.appspot.com/10325043/

Affected files:
   A [revision details]
   M cmd/juju/ssh.go
   M cmd/juju/ssh_test.go
   M cmd/juju/status.go
   M cmd/jujud/bootstrap_test.go
   M environs/azure/environ.go
   M environs/azure/environprovider.go
   M environs/azure/instance.go
   M environs/dummy/environs.go
   M environs/ec2/ec2.go
   M environs/ec2/export_test.go
   M environs/ec2/live_test.go
   M environs/ec2/local_test.go
   M environs/ec2/state.go
   M environs/interface.go
   M environs/jujutest/livetests.go
   M environs/jujutest/tests.go
   M environs/maas/environ.go
   M environs/maas/environ_test.go
   M environs/maas/environprovider.go
   M environs/maas/environprovider_test.go
   M environs/maas/instance.go
   M environs/maas/state.go
   M environs/maas/util.go
   M environs/maas/util_test.go
   M environs/openstack/export_test.go
   M environs/openstack/local_test.go
   M environs/openstack/provider.go
   M environs/openstack/state.go
   M instance/instance.go
   M state/apiserver/api_test.go
   M state/machine.go
   M state/machine_test.go
   M state/megawatcher_internal_test.go
   M state/state.go
   M state/state_test.go
   M worker/firewaller/firewaller.go
   M worker/provisioner/provisioner_task.go
   M worker/provisioner/provisioner_test.go

[Ian Booth (wallyworld)]

LGTM with the rename suggestion.

https://codereview.appspot.com/10325043/diff/1/environs/maas/instance.go
File environs/maas/instance.go (right):

https://codereview.appspot.com/10325043/diff/1/environs/maas/instance.go#newcode20
environs/maas/instance.go:20: func (this *maasInstance) Id() instance.Id
{
The usual convention would be something like:
func (mi *maasInstance) Id() instance.Id {

https://codereview.appspot.com/10325043/

[Go Bot (go-bot)]

There are additional revisions which have not been approved in review. Please seek review and approval of these new revisions.

=== modified file 'cmd/juju/ssh.go'
--- cmd/juju/ssh.go	2013-05-02 15:55:42 +0000
+++ cmd/juju/ssh.go	2013-06-17 21:39:25 +0000
@@ -7,6 +7,7 @@
 	"errors"
 	"fmt"
 	"launchpad.net/juju-core/cmd"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/juju"
 	"launchpad.net/juju-core/log"
 	"launchpad.net/juju-core/state"
@@ -105,7 +106,7 @@
 	for _ = range w.Changes() {
 		if instid, ok := machine.InstanceId(); ok {
 			w.Stop()
-			inst, err := c.Environ.Instances([]state.InstanceId{instid})
+			inst, err := c.Environ.Instances([]instance.Id{instid})
 			if err != nil {
 				return "", err
 			}
 
=== modified file 'cmd/juju/ssh_test.go'
--- cmd/juju/ssh_test.go	2013-05-27 03:17:41 +0000
+++ cmd/juju/ssh_test.go	2013-06-17 21:39:25 +0000
@@ -9,6 +9,7 @@
 	. "launchpad.net/gocheck"
 	"launchpad.net/juju-core/charm"
 	"launchpad.net/juju-core/cmd"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/juju/testing"
 	"launchpad.net/juju-core/state"
 	coretesting "launchpad.net/juju-core/testing"
@@ -139,7 +140,7 @@
 	// fudge unit.SetPublicAddress
 	id, ok := m.InstanceId()
 	c.Assert(ok, Equals, true)
-	insts, err := s.Conn.Environ.Instances([]state.InstanceId{id})
+	insts, err := s.Conn.Environ.Instances([]instance.Id{id})
 	c.Assert(err, IsNil)
 	addr, err := insts[0].WaitDNSName()
 	c.Assert(err, IsNil)
 
=== modified file 'cmd/juju/status.go'
--- cmd/juju/status.go	2013-06-16 22:10:37 +0000
+++ cmd/juju/status.go	2013-06-17 21:39:25 +0000
@@ -43,7 +43,7 @@
 }
 
 type statusContext struct {
-	instances map[state.InstanceId]instance.Instance
+	instances map[instance.Id]instance.Instance
 	machines  map[string][]*state.Machine
 	services  map[string]*state.Service
 	units     map[string]map[string]*state.Unit
@@ -80,8 +80,8 @@
 }
 
 // fetchAllInstances returns a map from instance id to instance.
-func fetchAllInstances(env environs.Environ) (map[state.InstanceId]instance.Instance, error) {
-	m := make(map[state.InstanceId]instance.Instance)
+func fetchAllInstances(env environs.Environ) (map[instance.Id]instance.Instance, error) {
+	m := make(map[instance.Id]instance.Instance)
 	insts, err := env.AllInstances()
 	if err != nil {
 		return nil, err
@@ -357,7 +357,7 @@
 	AgentStateInfo string                   `json:"agent-state-info,omitempty" yaml:"agent-state-info,omitempty"`
 	AgentVersion   string                   `json:"agent-version,omitempty" yaml:"agent-version,omitempty"`
 	DNSName        string                   `json:"dns-name,omitempty" yaml:"dns-name,omitempty"`
-	InstanceId     state.InstanceId         `json:"instance-id,omitempty" yaml:"instance-id,omitempty"`
+	InstanceId     instance.Id              `json:"instance-id,omitempty" yaml:"instance-id,omitempty"`
 	InstanceState  string                   `json:"instance-state,omitempty" yaml:"instance-state,omitempty"`
 	Life           string                   `json:"life,omitempty" yaml:"life,omitempty"`
 	Series         string                   `json:"series,omitempty" yaml:"series,omitempty"`
 
=== modified file 'cmd/jujud/bootstrap_test.go'
--- cmd/jujud/bootstrap_test.go	2013-06-11 13:52:19 +0000
+++ cmd/jujud/bootstrap_test.go	2013-06-17 21:39:25 +0000
@@ -10,6 +10,7 @@
 	"launchpad.net/juju-core/constraints"
 	"launchpad.net/juju-core/environs/agent"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/testing"
 )
@@ -79,7 +80,7 @@
 
 	instid, ok := machines[0].InstanceId()
 	c.Assert(ok, Equals, true)
-	c.Assert(instid, Equals, state.InstanceId("dummy.instance.id"))
+	c.Assert(instid, Equals, instance.Id("dummy.instance.id"))
 
 	cons, err := st.EnvironConstraints()
 	c.Assert(err, IsNil)
 
=== modified file 'environs/azure/environ.go'
--- environs/azure/environ.go	2013-06-14 01:02:53 +0000
+++ environs/azure/environ.go	2013-06-17 21:39:25 +0000
@@ -54,7 +54,7 @@
 }
 
 // Instances is specified in the Environ interface.
-func (env *azureEnviron) Instances(ids []state.InstanceId) ([]instance.Instance, error) {
+func (env *azureEnviron) Instances(ids []instance.Id) ([]instance.Instance, error) {
 	panic("unimplemented")
 }
 
 
=== modified file 'environs/azure/environprovider.go'
--- environs/azure/environprovider.go	2013-06-11 12:41:10 +0000
+++ environs/azure/environprovider.go	2013-06-17 21:39:25 +0000
@@ -6,7 +6,7 @@
 import (
 	"launchpad.net/juju-core/environs"
 	"launchpad.net/juju-core/environs/config"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 )
 
 type azureEnvironProvider struct{}
@@ -45,6 +45,6 @@
 }
 
 // InstanceId is specified in the EnvironProvider interface.
-func (prov azureEnvironProvider) InstanceId() (state.InstanceId, error) {
+func (prov azureEnvironProvider) InstanceId() (instance.Id, error) {
 	panic("unimplemented")
 }
 
=== modified file 'environs/azure/instance.go'
--- environs/azure/instance.go	2013-06-14 01:02:53 +0000
+++ environs/azure/instance.go	2013-06-17 21:39:25 +0000
@@ -5,7 +5,6 @@
 
 import (
 	"launchpad.net/juju-core/instance"
-	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api/params"
 )
 
@@ -15,7 +14,7 @@
 var _ instance.Instance = (*azureInstance)(nil)
 
 // Id is specified in the Instance interface.
-func (instance *azureInstance) Id() state.InstanceId {
+func (instance *azureInstance) Id() instance.Id {
 	panic("unimplemented")
 }
 
 
=== modified file 'environs/dummy/environs.go'
--- environs/dummy/environs.go	2013-06-17 15:12:53 +0000
+++ environs/dummy/environs.go	2013-06-17 21:39:25 +0000
@@ -91,14 +91,14 @@
 type OpOpenPorts struct {
 	Env        string
 	MachineId  string
-	InstanceId state.InstanceId
+	InstanceId instance.Id
 	Ports      []params.Port
 }
 
 type OpClosePorts struct {
 	Env        string
 	MachineId  string
-	InstanceId state.InstanceId
+	InstanceId instance.Id
 	Ports      []params.Port
 }
 
@@ -126,7 +126,7 @@
 	ops           chan<- Operation
 	mu            sync.Mutex
 	maxId         int // maximum instance id allocated so far.
-	insts         map[state.InstanceId]*dummyInstance
+	insts         map[instance.Id]*dummyInstance
 	globalPorts   map[params.Port]bool
 	firewallMode  config.FirewallMode
 	bootstrapped  bool
@@ -228,7 +228,7 @@
 	s := &environState{
 		name:         name,
 		ops:          ops,
-		insts:        make(map[state.InstanceId]*dummyInstance),
+		insts:        make(map[instance.Id]*dummyInstance),
 		globalPorts:  make(map[params.Port]bool),
 		firewallMode: fwmode,
 	}
@@ -389,8 +389,8 @@
 	return "private.dummy.address.example.com", nil
 }
 
-func (*environProvider) InstanceId() (state.InstanceId, error) {
-	return state.InstanceId("dummy.instance.id"), nil
+func (*environProvider) InstanceId() (instance.Id, error) {
+	return instance.Id("dummy.instance.id"), nil
 }
 
 func (*environProvider) BoilerplateConfig() string {
@@ -561,7 +561,7 @@
 	}
 	i := &dummyInstance{
 		state:     e.state,
-		id:        state.InstanceId(fmt.Sprintf("%s-%d", e.state.name, e.state.maxId)),
+		id:        instance.Id(fmt.Sprintf("%s-%d", e.state.name, e.state.maxId)),
 		ports:     make(map[params.Port]bool),
 		machineId: machineId,
 		series:    series,
@@ -598,7 +598,7 @@
 	return nil
 }
 
-func (e *environ) Instances(ids []state.InstanceId) (insts []instance.Instance, err error) {
+func (e *environ) Instances(ids []instance.Id) (insts []instance.Instance, err error) {
 	defer delay()
 	if err := e.checkBroken("Instances"); err != nil {
 		return nil, err
@@ -684,12 +684,12 @@
 type dummyInstance struct {
 	state     *environState
 	ports     map[params.Port]bool
-	id        state.InstanceId
+	id        instance.Id
 	machineId string
 	series    string
 }
 
-func (inst *dummyInstance) Id() state.InstanceId {
+func (inst *dummyInstance) Id() instance.Id {
 	return inst.id
 }
 
 
=== modified file 'environs/ec2/ec2.go'
--- environs/ec2/ec2.go	2013-06-17 15:12:53 +0000
+++ environs/ec2/ec2.go	2013-06-17 21:39:25 +0000
@@ -77,8 +77,8 @@
 
 var _ instance.Instance = (*ec2Instance)(nil)
 
-func (inst *ec2Instance) Id() state.InstanceId {
-	return state.InstanceId(inst.InstanceId)
+func (inst *ec2Instance) Id() instance.Id {
+	return instance.Id(inst.InstanceId)
 }
 
 func (inst *ec2Instance) DNSName() (string, error) {
@@ -87,7 +87,7 @@
 	}
 	// Fetch the instance information again, in case
 	// the DNS information has become available.
-	insts, err := inst.e.Instances([]state.InstanceId{inst.Id()})
+	insts, err := inst.e.Instances([]instance.Id{inst.Id()})
 	if err != nil {
 		return "", err
 	}
@@ -158,9 +158,9 @@
 	return fetchMetadata("local-hostname")
 }
 
-func (environProvider) InstanceId() (state.InstanceId, error) {
+func (environProvider) InstanceId() (instance.Id, error) {
 	str, err := fetchMetadata("instance-id")
-	return state.InstanceId(str), err
+	return instance.Id(str), err
 }
 
 func (e *environ) Config() *config.Config {
@@ -279,7 +279,7 @@
 		return fmt.Errorf("cannot start bootstrap instance: %v", err)
 	}
 	err = e.saveState(&bootstrapState{
-		StateInstances: []state.InstanceId{inst.Id()},
+		StateInstances: []instance.Id{inst.Id()},
 	})
 	if err != nil {
 		// ignore error on StopInstance because the previous error is
@@ -467,7 +467,7 @@
 }
 
 func (e *environ) StopInstances(insts []instance.Instance) error {
-	ids := make([]state.InstanceId, len(insts))
+	ids := make([]instance.Id, len(insts))
 	for i, inst := range insts {
 		ids[i] = inst.(*ec2Instance).Id()
 	}
@@ -478,7 +478,7 @@
 // id whose corresponding insts slot is nil.
 // It returns environs.ErrPartialInstances if the insts
 // slice has not been completely filled.
-func (e *environ) gatherInstances(ids []state.InstanceId, insts []instance.Instance) error {
+func (e *environ) gatherInstances(ids []instance.Id, insts []instance.Instance) error {
 	var need []string
 	for i, inst := range insts {
 		if inst == nil {
@@ -520,7 +520,7 @@
 	return nil
 }
 
-func (e *environ) Instances(ids []state.InstanceId) ([]instance.Instance, error) {
+func (e *environ) Instances(ids []instance.Id) ([]instance.Instance, error) {
 	if len(ids) == 0 {
 		return nil, nil
 	}
@@ -573,8 +573,8 @@
 	if err != nil {
 		return fmt.Errorf("cannot get instances: %v", err)
 	}
-	found := make(map[state.InstanceId]bool)
-	var ids []state.InstanceId
+	found := make(map[instance.Id]bool)
+	var ids []instance.Id
 	for _, inst := range insts {
 		ids = append(ids, inst.Id())
 		found[inst.Id()] = true
@@ -583,7 +583,7 @@
 	// Add any instances we've been told about but haven't yet shown
 	// up in the instance list.
 	for _, inst := range ensureInsts {
-		id := state.InstanceId(inst.(*ec2Instance).InstanceId)
+		id := instance.Id(inst.(*ec2Instance).InstanceId)
 		if !found[id] {
 			ids = append(ids, id)
 			found[id] = true
@@ -720,7 +720,7 @@
 	return &providerInstance
 }
 
-func (e *environ) terminateInstances(ids []state.InstanceId) error {
+func (e *environ) terminateInstances(ids []instance.Id) error {
 	if len(ids) == 0 {
 		return nil
 	}
 
=== modified file 'environs/ec2/export_test.go'
--- environs/ec2/export_test.go	2013-06-14 01:23:48 +0000
+++ environs/ec2/export_test.go	2013-06-17 21:39:25 +0000
@@ -12,13 +12,12 @@
 	"launchpad.net/juju-core/environs/imagemetadata"
 	"launchpad.net/juju-core/environs/jujutest"
 	"launchpad.net/juju-core/instance"
-	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/utils"
 	"net/http"
 )
 
 type BootstrapState struct {
-	StateInstances []state.InstanceId
+	StateInstances []instance.Id
 }
 
 func LoadState(e environs.Environ) (*BootstrapState, error) {
 
=== modified file 'environs/ec2/live_test.go'
--- environs/ec2/live_test.go	2013-06-14 01:02:53 +0000
+++ environs/ec2/live_test.go	2013-06-17 21:39:25 +0000
@@ -19,7 +19,6 @@
 	"launchpad.net/juju-core/errors"
 	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/juju/testing"
-	"launchpad.net/juju-core/state"
 	coretesting "launchpad.net/juju-core/testing"
 	"strings"
 )
@@ -120,7 +119,7 @@
 	c.Assert(err, IsNil)
 	c.Assert(dns, Not(Equals), "")
 
-	insts, err := t.Env.Instances([]state.InstanceId{inst.Id()})
+	insts, err := t.Env.Instances([]instance.Id{inst.Id()})
 	c.Assert(err, IsNil)
 	c.Assert(len(insts), Equals, 1)
 
@@ -230,7 +229,7 @@
 		msg := Commentf("reservation %#v", r)
 		c.Assert(hasSecurityGroup(r, groups[0]), Equals, true, msg)
 		inst := r.Instances[0]
-		switch state.InstanceId(inst.InstanceId) {
+		switch instance.Id(inst.InstanceId) {
 		case inst0.Id():
 			c.Assert(hasSecurityGroup(r, groups[1]), Equals, true, msg)
 			c.Assert(hasSecurityGroup(r, groups[2]), Equals, false, msg)
@@ -325,7 +324,7 @@
 	// if it succeeds.
 	gone := false
 	for a := ec2.ShortAttempt.Start(); a.Next(); {
-		insts, err = t.Env.Instances([]state.InstanceId{inst0.Id(), inst2.Id()})
+		insts, err = t.Env.Instances([]instance.Id{inst0.Id(), inst2.Id()})
 		if err == environs.ErrPartialInstances {
 			// instances not gone yet.
 			continue
 
=== modified file 'environs/ec2/local_test.go'
--- environs/ec2/local_test.go	2013-05-28 08:05:49 +0000
+++ environs/ec2/local_test.go	2013-06-17 21:39:25 +0000
@@ -18,7 +18,7 @@
 	"launchpad.net/juju-core/environs/imagemetadata"
 	"launchpad.net/juju-core/environs/jujutest"
 	envtesting "launchpad.net/juju-core/environs/testing"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/testing"
 	"launchpad.net/juju-core/utils"
 	"regexp"
@@ -50,7 +50,7 @@
 
 	id, err := p.InstanceId()
 	c.Assert(err, IsNil)
-	c.Assert(id, Equals, state.InstanceId("dummy.instance.id"))
+	c.Assert(id, Equals, instance.Id("dummy.instance.id"))
 }
 
 func registerLocalTests() {
 
=== modified file 'environs/ec2/state.go'
--- environs/ec2/state.go	2013-05-02 15:55:42 +0000
+++ environs/ec2/state.go	2013-06-17 21:39:25 +0000
@@ -8,13 +8,13 @@
 	"fmt"
 	"io/ioutil"
 	"launchpad.net/goyaml"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 )
 
 const stateFile = "provider-state"
 
 type bootstrapState struct {
-	StateInstances []state.InstanceId `yaml:"state-instances"`
+	StateInstances []instance.Id `yaml:"state-instances"`
 }
 
 func (e *environ) saveState(state *bootstrapState) error {
 
=== modified file 'environs/interface.go'
--- environs/interface.go	2013-06-14 01:02:53 +0000
+++ environs/interface.go	2013-06-17 21:39:25 +0000
@@ -47,7 +47,7 @@
 	PrivateAddress() (string, error)
 
 	// InstanceId returns this machine's instance id.
-	InstanceId() (state.InstanceId, error)
+	InstanceId() (instance.Id, error)
 }
 
 var ErrNoInstances = errors.New("no instances found")
@@ -146,7 +146,7 @@
 	// some but not all the instances were found, the returned slice
 	// will have some nil slots, and an ErrPartialInstances error
 	// will be returned.
-	Instances(ids []state.InstanceId) ([]instance.Instance, error)
+	Instances(ids []instance.Id) ([]instance.Instance, error)
 
 	// AllInstances returns all instances currently known to the
 	// environment.
 
=== modified file 'environs/jujutest/livetests.go'
--- environs/jujutest/livetests.go	2013-06-17 15:12:53 +0000
+++ environs/jujutest/livetests.go	2013-06-17 21:39:25 +0000
@@ -113,7 +113,7 @@
 	c.Assert(inst, NotNil)
 	id0 := inst.Id()
 
-	insts, err := t.Env.Instances([]state.InstanceId{id0, id0})
+	insts, err := t.Env.Instances([]instance.Id{id0, id0})
 	c.Assert(err, IsNil)
 	c.Assert(insts, HasLen, 2)
 	c.Assert(insts[0].Id(), Equals, id0)
@@ -138,7 +138,7 @@
 	c.Assert(err, IsNil)
 	c.Assert(dns, Not(Equals), "")
 
-	insts, err = t.Env.Instances([]state.InstanceId{id0, ""})
+	insts, err = t.Env.Instances([]instance.Id{id0, ""})
 	c.Assert(err, Equals, environs.ErrPartialInstances)
 	c.Assert(insts, HasLen, 2)
 	c.Check(insts[0].Id(), Equals, id0)
@@ -150,7 +150,7 @@
 	// The machine may not be marked as shutting down
 	// immediately. Repeat a few times to ensure we get the error.
 	for a := t.Attempt.Start(); a.Next(); {
-		insts, err = t.Env.Instances([]state.InstanceId{id0})
+		insts, err = t.Env.Instances([]instance.Id{id0})
 		if err != nil {
 			break
 		}
@@ -621,17 +621,17 @@
 		if !ok {
 			continue
 		}
-		_, err = t.Env.Instances([]state.InstanceId{instId})
+		_, err = t.Env.Instances([]instance.Id{instId})
 		c.Assert(err, IsNil)
 		return
 	}
 	c.Fatalf("provisioner failed to start machine after %v", waitAgent.Total)
 }
 
-func (t *LiveTests) assertStopInstance(c *C, env environs.Environ, instId state.InstanceId) {
+func (t *LiveTests) assertStopInstance(c *C, env environs.Environ, instId instance.Id) {
 	var err error
 	for a := waitAgent.Start(); a.Next(); {
-		_, err = t.Env.Instances([]state.InstanceId{instId})
+		_, err = t.Env.Instances([]instance.Id{instId})
 		if err == nil {
 			continue
 		}
@@ -647,7 +647,7 @@
 // that matches that of the given instance. If the instance is nil,
 // It asserts that the instance id is unset.
 func assertInstanceId(c *C, m *state.Machine, inst instance.Instance) {
-	var wantId, gotId state.InstanceId
+	var wantId, gotId instance.Id
 	var err error
 	if inst != nil {
 		wantId = inst.Id()
 
=== modified file 'environs/jujutest/tests.go'
--- environs/jujutest/tests.go	2013-06-14 01:02:53 +0000
+++ environs/jujutest/tests.go	2013-06-17 21:39:25 +0000
@@ -14,7 +14,6 @@
 	"launchpad.net/juju-core/errors"
 	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/juju/testing"
-	"launchpad.net/juju-core/state"
 	coretesting "launchpad.net/juju-core/testing"
 	"launchpad.net/juju-core/utils"
 	"launchpad.net/juju-core/version"
@@ -96,7 +95,7 @@
 	c.Assert(inst1, NotNil)
 	id1 := inst1.Id()
 
-	insts, err = e.Instances([]state.InstanceId{id0, id1})
+	insts, err = e.Instances([]instance.Id{id0, id1})
 	c.Assert(err, IsNil)
 	c.Assert(insts, HasLen, 2)
 	c.Assert(insts[0].Id(), Equals, id0)
@@ -111,7 +110,7 @@
 	err = e.StopInstances([]instance.Instance{inst0})
 	c.Assert(err, IsNil)
 
-	insts, err = e.Instances([]state.InstanceId{id0, id1})
+	insts, err = e.Instances([]instance.Id{id0, id1})
 	c.Assert(err, Equals, environs.ErrPartialInstances)
 	c.Assert(insts[0], IsNil)
 	c.Assert(insts[1].Id(), Equals, id1)
 
=== modified file 'environs/maas/environ.go'
--- environs/maas/environ.go	2013-06-17 15:12:53 +0000
+++ environs/maas/environ.go	2013-06-17 21:39:25 +0000
@@ -116,7 +116,7 @@
 	if err != nil {
 		return err
 	}
-	err = env.saveState(&bootstrapState{StateInstances: []state.InstanceId{inst.Id()}})
+	err = env.saveState(&bootstrapState{StateInstances: []instance.Id{inst.Id()}})
 	if err != nil {
 		if err := env.releaseInstance(inst); err != nil {
 			log.Errorf("environs/maas: cannot release failed bootstrap instance: %v", err)
@@ -397,9 +397,9 @@
 }
 
 // Instances returns the instance.Instance objects corresponding to the given
-// slice of state.InstanceId.  Similar to what the ec2 provider does,
+// slice of instance.Id.  Similar to what the ec2 provider does,
 // Instances returns nil if the given slice is empty or nil.
-func (environ *maasEnviron) Instances(ids []state.InstanceId) ([]instance.Instance, error) {
+func (environ *maasEnviron) Instances(ids []instance.Id) ([]instance.Instance, error) {
 	if len(ids) == 0 {
 		return nil, nil
 	}
@@ -411,7 +411,7 @@
 // If the some of the intances could not be found, it returns the instance
 // that could be found plus the error environs.ErrPartialInstances in the error
 // return.
-func (environ *maasEnviron) instances(ids []state.InstanceId) ([]instance.Instance, error) {
+func (environ *maasEnviron) instances(ids []instance.Id) ([]instance.Instance, error) {
 	nodeListing := environ.getMAASClient().GetSubObject("nodes")
 	filter := getSystemIdValues(ids)
 	listNodeObjects, err := nodeListing.CallGet("list", filter)
@@ -463,7 +463,7 @@
 	if err != nil {
 		return fmt.Errorf("cannot get instances: %v", err)
 	}
-	found := make(map[state.InstanceId]bool)
+	found := make(map[instance.Id]bool)
 	for _, inst := range insts {
 		found[inst.Id()] = true
 	}
 
=== modified file 'environs/maas/environ_test.go'
--- environs/maas/environ_test.go	2013-06-14 01:23:48 +0000
+++ environs/maas/environ_test.go	2013-06-17 21:39:25 +0000
@@ -16,7 +16,6 @@
 	"launchpad.net/juju-core/environs/tools"
 	"launchpad.net/juju-core/errors"
 	"launchpad.net/juju-core/instance"
-	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/testing"
 	"launchpad.net/juju-core/utils"
 	"launchpad.net/juju-core/version"
@@ -134,7 +133,7 @@
 	input := `{"system_id": "test"}`
 	node := suite.testMAASObject.TestServer.NewNode(input)
 	resourceURI, _ := node.GetField("resource_uri")
-	instanceIds := []state.InstanceId{state.InstanceId(resourceURI)}
+	instanceIds := []instance.Id{instance.Id(resourceURI)}
 
 	instances, err := suite.environ.Instances(instanceIds)
 
@@ -147,7 +146,7 @@
 	// Instances returns nil if the given parameter is empty.
 	input := `{"system_id": "test"}`
 	suite.testMAASObject.TestServer.NewNode(input)
-	instances, err := suite.environ.Instances([]state.InstanceId{})
+	instances, err := suite.environ.Instances([]instance.Id{})
 
 	c.Check(err, IsNil)
 	c.Check(instances, IsNil)
@@ -188,9 +187,9 @@
 	resourceURI1, _ := node1.GetField("resource_uri")
 	input2 := `{"system_id": "test2"}`
 	suite.testMAASObject.TestServer.NewNode(input2)
-	instanceId1 := state.InstanceId(resourceURI1)
-	instanceId2 := state.InstanceId("unknown systemID")
-	instanceIds := []state.InstanceId{instanceId1, instanceId2}
+	instanceId1 := instance.Id(resourceURI1)
+	instanceId2 := instance.Id("unknown systemID")
+	instanceIds := []instance.Id{instanceId1, instanceId2}
 
 	instances, err := suite.environ.Instances(instanceIds)
 
@@ -370,8 +369,8 @@
 	hostname := "test"
 	input := `{"system_id": "system_id", "hostname": "` + hostname + `"}`
 	node := suite.testMAASObject.TestServer.NewNode(input)
-	instance := &maasInstance{&node, suite.environ}
-	err := env.saveState(&bootstrapState{StateInstances: []state.InstanceId{instance.Id()}})
+	testInstance := &maasInstance{&node, suite.environ}
+	err := env.saveState(&bootstrapState{StateInstances: []instance.Id{testInstance.Id()}})
 	c.Assert(err, IsNil)
 
 	stateInfo, apiInfo, err := env.StateInfo()
 
=== modified file 'environs/maas/environprovider.go'
--- environs/maas/environprovider.go	2013-05-02 15:55:42 +0000
+++ environs/maas/environprovider.go	2013-06-17 21:39:25 +0000
@@ -6,8 +6,8 @@
 import (
 	"launchpad.net/juju-core/environs"
 	"launchpad.net/juju-core/environs/config"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/log"
-	"launchpad.net/juju-core/state"
 )
 
 type maasEnvironProvider struct{}
@@ -78,11 +78,11 @@
 }
 
 // InstanceId is specified in the EnvironProvider interface.
-func (maasEnvironProvider) InstanceId() (state.InstanceId, error) {
+func (maasEnvironProvider) InstanceId() (instance.Id, error) {
 	info := machineInfo{}
 	err := info.load()
 	if err != nil {
 		return "", err
 	}
-	return state.InstanceId(info.InstanceId), nil
+	return instance.Id(info.InstanceId), nil
 }
 
=== modified file 'environs/maas/environprovider_test.go'
--- environs/maas/environprovider_test.go	2013-05-02 15:55:42 +0000
+++ environs/maas/environprovider_test.go	2013-06-17 21:39:25 +0000
@@ -8,7 +8,7 @@
 	. "launchpad.net/gocheck"
 	"launchpad.net/goyaml"
 	"launchpad.net/juju-core/environs/config"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 )
 
 type EnvironProviderSuite struct {
@@ -68,7 +68,7 @@
 	provider := suite.environ.Provider()
 	returnedInstanceId, err := provider.InstanceId()
 	c.Assert(err, IsNil)
-	c.Check(returnedInstanceId, Equals, state.InstanceId(instanceId))
+	c.Check(returnedInstanceId, Equals, instance.Id(instanceId))
 }
 
 // PublicAddress and PrivateAddress return the hostname of the machine read
 
=== modified file 'environs/maas/instance.go'
--- environs/maas/instance.go	2013-06-14 01:02:53 +0000
+++ environs/maas/instance.go	2013-06-17 21:39:25 +0000
@@ -7,7 +7,6 @@
 	"launchpad.net/gomaasapi"
 	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/log"
-	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api/params"
 )
 
@@ -18,20 +17,20 @@
 
 var _ instance.Instance = (*maasInstance)(nil)
 
-func (instance *maasInstance) Id() state.InstanceId {
+func (mi *maasInstance) Id() instance.Id {
 	// Use the node's 'resource_uri' value.
-	return state.InstanceId((*instance.maasObject).URI().String())
+	return instance.Id((*mi.maasObject).URI().String())
 }
 
 // refreshInstance refreshes the instance with the most up-to-date information
 // from the MAAS server.
-func (instance *maasInstance) refreshInstance() error {
-	insts, err := instance.environ.Instances([]state.InstanceId{instance.Id()})
+func (mi *maasInstance) refreshInstance() error {
+	insts, err := mi.environ.Instances([]instance.Id{mi.Id()})
 	if err != nil {
 		return err
 	}
 	newMaasObject := insts[0].(*maasInstance).maasObject
-	instance.maasObject = newMaasObject
+	mi.maasObject = newMaasObject
 	return nil
 }
 
 
=== modified file 'environs/maas/state.go'
--- environs/maas/state.go	2013-05-02 15:55:42 +0000
+++ environs/maas/state.go	2013-06-17 21:39:25 +0000
@@ -8,7 +8,7 @@
 	"fmt"
 	"io/ioutil"
 	"launchpad.net/goyaml"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 )
 
 const stateFile = "provider-state"
@@ -16,7 +16,7 @@
 // Persistent environment state.  An environment needs to know what instances
 // it manages.
 type bootstrapState struct {
-	StateInstances []state.InstanceId `yaml:"state-instances"`
+	StateInstances []instance.Id `yaml:"state-instances"`
 }
 
 // saveState writes the environment's state to the provider-state file stored
 
=== modified file 'environs/maas/util.go'
--- environs/maas/util.go	2013-05-02 15:55:42 +0000
+++ environs/maas/util.go	2013-06-17 21:39:25 +0000
@@ -8,8 +8,8 @@
 	"launchpad.net/goyaml"
 	cloudinit_core "launchpad.net/juju-core/cloudinit"
 	"launchpad.net/juju-core/environs/cloudinit"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/log"
-	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/utils"
 	"net/url"
 	"strings"
@@ -17,7 +17,7 @@
 
 // extractSystemId extracts the 'system_id' part from an InstanceId.
 // "/MAAS/api/1.0/nodes/system_id/" => "system_id"
-func extractSystemId(instanceId state.InstanceId) string {
+func extractSystemId(instanceId instance.Id) string {
 	trimmed := strings.TrimRight(string(instanceId), "/")
 	split := strings.Split(trimmed, "/")
 	return split[len(split)-1]
@@ -26,7 +26,7 @@
 // getSystemIdValues returns a url.Values object with all the 'system_ids'
 // from the given instanceIds stored under the key 'id'.  This is used
 // to filter out instances when listing the nodes objects.
-func getSystemIdValues(instanceIds []state.InstanceId) url.Values {
+func getSystemIdValues(instanceIds []instance.Id) url.Values {
 	values := url.Values{}
 	for _, instanceId := range instanceIds {
 		values.Add("id", extractSystemId(instanceId))
 
=== modified file 'environs/maas/util_test.go'
--- environs/maas/util_test.go	2013-05-31 07:39:15 +0000
+++ environs/maas/util_test.go	2013-06-17 21:39:25 +0000
@@ -9,6 +9,7 @@
 	"launchpad.net/goyaml"
 	"launchpad.net/juju-core/environs/cloudinit"
 	"launchpad.net/juju-core/environs/config"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api"
 	"launchpad.net/juju-core/testing"
@@ -21,7 +22,7 @@
 var _ = Suite(&UtilSuite{})
 
 func (s *UtilSuite) TestExtractSystemId(c *C) {
-	instanceId := state.InstanceId("/MAAS/api/1.0/nodes/system_id/")
+	instanceId := instance.Id("/MAAS/api/1.0/nodes/system_id/")
 
 	systemId := extractSystemId(instanceId)
 
@@ -29,9 +30,9 @@
 }
 
 func (s *UtilSuite) TestGetSystemIdValues(c *C) {
-	instanceId1 := state.InstanceId("/MAAS/api/1.0/nodes/system_id1/")
-	instanceId2 := state.InstanceId("/MAAS/api/1.0/nodes/system_id2/")
-	instanceIds := []state.InstanceId{instanceId1, instanceId2}
+	instanceId1 := instance.Id("/MAAS/api/1.0/nodes/system_id1/")
+	instanceId2 := instance.Id("/MAAS/api/1.0/nodes/system_id2/")
+	instanceIds := []instance.Id{instanceId1, instanceId2}
 
 	values := getSystemIdValues(instanceIds)
 
 
=== modified file 'environs/openstack/export_test.go'
--- environs/openstack/export_test.go	2013-05-30 05:39:33 +0000
+++ environs/openstack/export_test.go	2013-06-17 21:39:25 +0000
@@ -15,7 +15,7 @@
 	"launchpad.net/juju-core/environs/instances"
 	"launchpad.net/juju-core/environs/jujutest"
 	"launchpad.net/juju-core/environs/tools"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/utils"
 	"net/http"
 	"strings"
@@ -286,7 +286,7 @@
 }
 
 type BootstrapState struct {
-	StateInstances []state.InstanceId
+	StateInstances []instance.Id
 }
 
 func LoadState(e environs.Environ) (*BootstrapState, error) {
 
=== modified file 'environs/openstack/local_test.go'
--- environs/openstack/local_test.go	2013-06-14 01:02:53 +0000
+++ environs/openstack/local_test.go	2013-06-17 21:39:25 +0000
@@ -19,7 +19,6 @@
 	envtesting "launchpad.net/juju-core/environs/testing"
 	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/juju/testing"
-	"launchpad.net/juju-core/state"
 	coretesting "launchpad.net/juju-core/testing"
 	"launchpad.net/juju-core/version"
 	"net/http"
@@ -56,7 +55,7 @@
 
 	id, err := p.InstanceId()
 	c.Assert(err, IsNil)
-	c.Assert(id, Equals, state.InstanceId("d8e02d56-2648-49a3-bf97-6be8f1204f38"))
+	c.Assert(id, Equals, instance.Id("d8e02d56-2648-49a3-bf97-6be8f1204f38"))
 }
 
 func (s *ProviderSuite) TestPublicFallbackToPrivate(c *C) {
@@ -90,7 +89,7 @@
 
 	id, err := p.InstanceId()
 	c.Assert(err, IsNil)
-	c.Assert(id, Equals, state.InstanceId("2748"))
+	c.Assert(id, Equals, instance.Id("2748"))
 }
 
 // Register tests to run against a test Openstack instance (service doubles).
@@ -287,48 +286,48 @@
 }
 
 var instanceGathering = []struct {
-	ids []state.InstanceId
+	ids []instance.Id
 	err error
 }{
-	{ids: []state.InstanceId{"id0"}},
-	{ids: []state.InstanceId{"id0", "id0"}},
-	{ids: []state.InstanceId{"id0", "id1"}},
-	{ids: []state.InstanceId{"id1", "id0"}},
-	{ids: []state.InstanceId{"id1", "id0", "id1"}},
-	{
-		ids: []state.InstanceId{""},
-		err: environs.ErrNoInstances,
-	},
-	{
-		ids: []state.InstanceId{"", ""},
-		err: environs.ErrNoInstances,
-	},
-	{
-		ids: []state.InstanceId{"", "", ""},
-		err: environs.ErrNoInstances,
-	},
-	{
-		ids: []state.InstanceId{"id0", ""},
-		err: environs.ErrPartialInstances,
-	},
-	{
-		ids: []state.InstanceId{"", "id1"},
-		err: environs.ErrPartialInstances,
-	},
-	{
-		ids: []state.InstanceId{"id0", "id1", ""},
-		err: environs.ErrPartialInstances,
-	},
-	{
-		ids: []state.InstanceId{"id0", "", "id0"},
-		err: environs.ErrPartialInstances,
-	},
-	{
-		ids: []state.InstanceId{"id0", "id0", ""},
-		err: environs.ErrPartialInstances,
-	},
-	{
-		ids: []state.InstanceId{"", "id0", "id1"},
+	{ids: []instance.Id{"id0"}},
+	{ids: []instance.Id{"id0", "id0"}},
+	{ids: []instance.Id{"id0", "id1"}},
+	{ids: []instance.Id{"id1", "id0"}},
+	{ids: []instance.Id{"id1", "id0", "id1"}},
+	{
+		ids: []instance.Id{""},
+		err: environs.ErrNoInstances,
+	},
+	{
+		ids: []instance.Id{"", ""},
+		err: environs.ErrNoInstances,
+	},
+	{
+		ids: []instance.Id{"", "", ""},
+		err: environs.ErrNoInstances,
+	},
+	{
+		ids: []instance.Id{"id0", ""},
+		err: environs.ErrPartialInstances,
+	},
+	{
+		ids: []instance.Id{"", "id1"},
+		err: environs.ErrPartialInstances,
+	},
+	{
+		ids: []instance.Id{"id0", "id1", ""},
+		err: environs.ErrPartialInstances,
+	},
+	{
+		ids: []instance.Id{"id0", "", "id0"},
+		err: environs.ErrPartialInstances,
+	},
+	{
+		ids: []instance.Id{"id0", "id0", ""},
+		err: environs.ErrPartialInstances,
+	},
+	{
+		ids: []instance.Id{"", "id0", "id1"},
 		err: environs.ErrPartialInstances,
 	},
 }
@@ -345,7 +344,7 @@
 
 	for i, test := range instanceGathering {
 		c.Logf("test %d: find %v -> expect len %d, err: %v", i, test.ids, len(test.ids), test.err)
-		ids := make([]state.InstanceId, len(test.ids))
+		ids := make([]instance.Id, len(test.ids))
 		for j, id := range test.ids {
 			switch id {
 			case "id0":
 
=== modified file 'environs/openstack/provider.go'
--- environs/openstack/provider.go	2013-06-17 15:12:53 +0000
+++ environs/openstack/provider.go	2013-06-17 21:39:25 +0000
@@ -159,12 +159,12 @@
 	return fetchMetadata("local-ipv4")
 }
 
-func (p environProvider) InstanceId() (state.InstanceId, error) {
+func (p environProvider) InstanceId() (instance.Id, error) {
 	str, err := fetchInstanceUUID()
 	if err != nil {
 		str, err = fetchLegacyId()
 	}
-	return state.InstanceId(str), err
+	return instance.Id(str), err
 }
 
 // metadataHost holds the address of the instance metadata service.
@@ -283,8 +283,8 @@
 
 var _ instance.Instance = (*openstackInstance)(nil)
 
-func (inst *openstackInstance) Id() state.InstanceId {
-	return state.InstanceId(inst.ServerDetail.Id)
+func (inst *openstackInstance) Id() instance.Id {
+	return instance.Id(inst.ServerDetail.Id)
 }
 
 // instanceAddress processes a map of networks to lists of IP
@@ -507,7 +507,7 @@
 		return fmt.Errorf("cannot start bootstrap instance: %v", err)
 	}
 	err = e.saveState(&bootstrapState{
-		StateInstances: []state.InstanceId{inst.Id()},
+		StateInstances: []instance.Id{inst.Id()},
 	})
 	if err != nil {
 		// ignore error on StopInstance because the previous error is
@@ -841,7 +841,7 @@
 	log.Infof("environs/openstack: started instance %q", inst.Id())
 	if scfg.withPublicIP {
 		if err := e.assignPublicIP(publicIP, string(inst.Id())); err != nil {
-			if err := e.terminateInstances([]state.InstanceId{inst.Id()}); err != nil {
+			if err := e.terminateInstances([]instance.Id{inst.Id()}); err != nil {
 				// ignore the failure at this stage, just log it
 				log.Debugf("environs/openstack: failed to terminate instance %q: %v", inst.Id(), err)
 			}
@@ -853,7 +853,7 @@
 }
 
 func (e *environ) StopInstances(insts []instance.Instance) error {
-	ids := make([]state.InstanceId, len(insts))
+	ids := make([]instance.Id, len(insts))
 	for i, inst := range insts {
 		instanceValue, ok := inst.(*openstackInstance)
 		if !ok {
@@ -868,7 +868,7 @@
 // collectInstances tries to get information on each instance id in ids.
 // It fills the slots in the given map for known servers with status
 // either ACTIVE or BUILD. Returns a list of missing ids.
-func (e *environ) collectInstances(ids []state.InstanceId, out map[state.InstanceId]instance.Instance) []state.InstanceId {
+func (e *environ) collectInstances(ids []instance.Id, out map[instance.Id]instance.Instance) []instance.Id {
 	var err error
 	serversById := make(map[string]nova.ServerDetail)
 	if len(ids) == 1 {
@@ -888,7 +888,7 @@
 	if err != nil {
 		return ids
 	}
-	var missing []state.InstanceId
+	var missing []instance.Id
 	for _, id := range ids {
 		if server, found := serversById[string(id)]; found {
 			if server.Status == nova.StatusActive || server.Status == nova.StatusBuild {
@@ -901,12 +901,12 @@
 	return missing
 }
 
-func (e *environ) Instances(ids []state.InstanceId) ([]instance.Instance, error) {
+func (e *environ) Instances(ids []instance.Id) ([]instance.Instance, error) {
 	if len(ids) == 0 {
 		return nil, nil
 	}
 	missing := ids
-	found := make(map[state.InstanceId]instance.Instance)
+	found := make(map[instance.Id]instance.Instance)
 	// Make a series of requests to cope with eventual consistency.
 	// Each request will attempt to add more instances to the requested
 	// set.
@@ -950,8 +950,8 @@
 	if err != nil {
 		return fmt.Errorf("cannot get instances: %v", err)
 	}
-	found := make(map[state.InstanceId]bool)
-	var ids []state.InstanceId
+	found := make(map[instance.Id]bool)
+	var ids []instance.Id
 	for _, inst := range insts {
 		ids = append(ids, inst.Id())
 		found[inst.Id()] = true
@@ -960,7 +960,7 @@
 	// Add any instances we've been told about but haven't yet shown
 	// up in the instance list.
 	for _, inst := range ensureInsts {
-		id := state.InstanceId(inst.(*openstackInstance).Id())
+		id := instance.Id(inst.(*openstackInstance).Id())
 		if !found[id] {
 			ids = append(ids, id)
 			found[id] = true
@@ -1190,7 +1190,7 @@
 	return *group, nil
 }
 
-func (e *environ) terminateInstances(ids []state.InstanceId) error {
+func (e *environ) terminateInstances(ids []instance.Id) error {
 	if len(ids) == 0 {
 		return nil
 	}
 
=== modified file 'environs/openstack/state.go'
--- environs/openstack/state.go	2013-05-02 15:55:42 +0000
+++ environs/openstack/state.go	2013-06-17 21:39:25 +0000
@@ -8,13 +8,13 @@
 	"fmt"
 	"io/ioutil"
 	"launchpad.net/goyaml"
-	"launchpad.net/juju-core/state"
+	"launchpad.net/juju-core/instance"
 )
 
 const stateFile = "provider-state"
 
 type bootstrapState struct {
-	StateInstances []state.InstanceId `yaml:"state-instances"`
+	StateInstances []instance.Id `yaml:"state-instances"`
 }
 
 func (e *environ) saveState(state *bootstrapState) error {
 
=== modified file 'instance/instance.go'
--- instance/instance.go	2013-06-14 00:43:05 +0000
+++ instance/instance.go	2013-06-17 21:39:25 +0000
@@ -6,16 +6,19 @@
 import (
 	"errors"
 
-	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api/params"
 )
 
 var ErrNoDNSName = errors.New("DNS name not allocated")
 
+// An instance Id is a provider-specific identifier associated with an
+// instance (physical or virtual machine allocated in the provider).
+type Id string
+
 // Instance represents the the realization of a machine in state.
 type Instance interface {
 	// Id returns a provider-generated identifier for the Instance.
-	Id() state.InstanceId
+	Id() Id
 
 	// DNSName returns the DNS name for the instance.
 	// If the name is not yet allocated, it will return
 
=== modified file 'state/apiserver/api_test.go'
--- state/apiserver/api_test.go	2013-06-05 12:03:14 +0000
+++ state/apiserver/api_test.go	2013-06-17 21:39:25 +0000
@@ -9,6 +9,7 @@
 	"launchpad.net/juju-core/constraints"
 	"launchpad.net/juju-core/environs/config"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/juju/testing"
 	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api"
@@ -203,7 +204,7 @@
 	m, err := s.State.AddMachine("series", state.JobManageEnviron)
 	c.Assert(err, IsNil)
 	c.Assert(m.Tag(), Equals, "machine-0")
-	err = m.SetProvisioned(state.InstanceId("i-"+m.Tag()), "fake_nonce")
+	err = m.SetProvisioned(instance.Id("i-"+m.Tag()), "fake_nonce")
 	c.Assert(err, IsNil)
 	setDefaultPassword(c, m)
 	setDefaultStatus(c, m)
@@ -237,7 +238,7 @@
 			err = m.SetConstraints(constraints.MustParse("mem=1G"))
 			c.Assert(err, IsNil)
 		}
-		err = m.SetProvisioned(state.InstanceId("i-"+m.Tag()), "fake_nonce")
+		err = m.SetProvisioned(instance.Id("i-"+m.Tag()), "fake_nonce")
 		c.Assert(err, IsNil)
 		setDefaultPassword(c, m)
 		setDefaultStatus(c, m)
 
=== modified file 'state/machine.go'
--- state/machine.go	2013-06-16 22:12:59 +0000
+++ state/machine.go	2013-06-17 21:39:25 +0000
@@ -9,6 +9,7 @@
 	"labix.org/v2/mgo/txn"
 	"launchpad.net/juju-core/constraints"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/state/api/params"
 	"launchpad.net/juju-core/state/presence"
 	"launchpad.net/juju-core/utils"
@@ -16,10 +17,6 @@
 	"time"
 )
 
-// An InstanceId is a provider-specific identifier associated with an
-// instance (physical or virtual machine allocated in the provider).
-type InstanceId string
-
 // Machine represents the state of a machine.
 type Machine struct {
 	st  *State
@@ -59,7 +56,7 @@
 	Nonce         string
 	Series        string
 	ContainerType string
-	InstanceId    InstanceId
+	InstanceId    instance.Id
 	Principals    []string
 	Life          Life
 	Tools         *Tools `bson:",omitempty"`
@@ -452,7 +449,7 @@
 
 // InstanceId returns the provider specific instance id for this machine
 // and whether it has been set.
-func (m *Machine) InstanceId() (InstanceId, bool) {
+func (m *Machine) InstanceId() (instance.Id, bool) {
 	return m.doc.InstanceId, m.doc.InstanceId != ""
 }
 
@@ -480,7 +477,7 @@
 
 // SetProvisioned sets the provider specific machine id and nonce for
 // this machine. Once set, the instance id cannot be changed.
-func (m *Machine) SetProvisioned(id InstanceId, nonce string) (err error) {
+func (m *Machine) SetProvisioned(id instance.Id, nonce string) (err error) {
 	defer utils.ErrorContextf(&err, "cannot set instance id of machine %q", m)
 
 	if id == "" || nonce == "" {
 
=== modified file 'state/machine_test.go'
--- state/machine_test.go	2013-06-14 02:27:04 +0000
+++ state/machine_test.go	2013-06-17 21:39:25 +0000
@@ -7,6 +7,7 @@
 	. "launchpad.net/gocheck"
 	"launchpad.net/juju-core/constraints"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api/params"
 	"launchpad.net/juju-core/version"
@@ -255,7 +256,7 @@
 	err = machine.Refresh()
 	c.Assert(err, IsNil)
 	iid, _ := machine.InstanceId()
-	c.Assert(iid, Equals, state.InstanceId("spaceship/0"))
+	c.Assert(iid, Equals, instance.Id("spaceship/0"))
 }
 
 func (s *MachineSuite) TestMachineInstanceIdCorrupt(c *C) {
@@ -271,7 +272,7 @@
 	c.Assert(err, IsNil)
 	iid, ok := machine.InstanceId()
 	c.Assert(ok, Equals, false)
-	c.Assert(iid, Equals, state.InstanceId(""))
+	c.Assert(iid, Equals, instance.Id(""))
 }
 
 func (s *MachineSuite) TestMachineInstanceIdMissing(c *C) {
 
=== modified file 'state/megawatcher_internal_test.go'
--- state/megawatcher_internal_test.go	2013-06-11 00:58:34 +0000
+++ state/megawatcher_internal_test.go	2013-06-17 21:39:25 +0000
@@ -10,6 +10,7 @@
 	. "launchpad.net/gocheck"
 	"launchpad.net/juju-core/charm"
 	"launchpad.net/juju-core/constraints"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/state/api/params"
 	"launchpad.net/juju-core/state/multiwatcher"
 	"launchpad.net/juju-core/state/watcher"
@@ -64,7 +65,7 @@
 	m, err := s.State.AddMachine("series", JobManageEnviron)
 	c.Assert(err, IsNil)
 	c.Assert(m.Tag(), Equals, "machine-0")
-	err = m.SetProvisioned(InstanceId("i-"+m.Tag()), "fake_nonce")
+	err = m.SetProvisioned(instance.Id("i-"+m.Tag()), "fake_nonce")
 	c.Assert(err, IsNil)
 	add(&params.MachineInfo{
 		Id:         "0",
@@ -140,7 +141,7 @@
 			Annotations: pairs,
 		})
 
-		err = m.SetProvisioned(InstanceId("i-"+m.Tag()), "fake_nonce")
+		err = m.SetProvisioned(instance.Id("i-"+m.Tag()), "fake_nonce")
 		c.Assert(err, IsNil)
 		err = m.SetStatus(params.StatusError, m.Tag())
 		c.Assert(err, IsNil)
 
=== modified file 'state/state.go'
--- state/state.go	2013-06-16 11:39:46 +0000
+++ state/state.go	2013-06-17 21:39:25 +0000
@@ -15,6 +15,7 @@
 	"launchpad.net/juju-core/constraints"
 	"launchpad.net/juju-core/environs/config"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/log"
 	"launchpad.net/juju-core/state/api/params"
 	"launchpad.net/juju-core/state/multiwatcher"
@@ -200,7 +201,7 @@
 // InjectMachine adds a new machine, corresponding to an existing provider
 // instance, configured to run the supplied jobs on the supplied series, using
 // the specified constraints.
-func (st *State) InjectMachine(series string, cons constraints.Value, instanceId InstanceId, jobs ...MachineJob) (m *Machine, err error) {
+func (st *State) InjectMachine(series string, cons constraints.Value, instanceId instance.Id, jobs ...MachineJob) (m *Machine, err error) {
 	if instanceId == "" {
 		return nil, fmt.Errorf("cannot inject a machine without an instance id")
 	}
@@ -275,7 +276,7 @@
 	Constraints   constraints.Value
 	ParentId      string
 	ContainerType ContainerType
-	instanceId    InstanceId
+	instanceId    instance.Id
 	nonce         string
 	Jobs          []MachineJob
 }
 
=== modified file 'state/state_test.go'
--- state/state_test.go	2013-06-16 11:39:46 +0000
+++ state/state_test.go	2013-06-17 21:39:25 +0000
@@ -11,6 +11,7 @@
 	"launchpad.net/juju-core/constraints"
 	"launchpad.net/juju-core/environs/config"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api/params"
 	"launchpad.net/juju-core/testing"
@@ -307,22 +308,22 @@
 }
 
 func (s *StateSuite) TestInjectMachineErrors(c *C) {
-	_, err := s.State.InjectMachine("", emptyCons, state.InstanceId("i-minvalid"), state.JobHostUnits)
+	_, err := s.State.InjectMachine("", emptyCons, instance.Id("i-minvalid"), state.JobHostUnits)
 	c.Assert(err, ErrorMatches, "cannot add a new machine: no series specified")
-	_, err = s.State.InjectMachine("series", emptyCons, state.InstanceId(""), state.JobHostUnits)
+	_, err = s.State.InjectMachine("series", emptyCons, instance.Id(""), state.JobHostUnits)
 	c.Assert(err, ErrorMatches, "cannot inject a machine without an instance id")
-	_, err = s.State.InjectMachine("series", emptyCons, state.InstanceId("i-mlazy"))
+	_, err = s.State.InjectMachine("series", emptyCons, instance.Id("i-mlazy"))
 	c.Assert(err, ErrorMatches, "cannot add a new machine: no jobs specified")
 }
 
 func (s *StateSuite) TestInjectMachine(c *C) {
 	cons := constraints.MustParse("mem=4G")
-	m, err := s.State.InjectMachine("series", cons, state.InstanceId("i-mindustrious"), state.JobHostUnits, state.JobManageEnviron)
+	m, err := s.State.InjectMachine("series", cons, instance.Id("i-mindustrious"), state.JobHostUnits, state.JobManageEnviron)
 	c.Assert(err, IsNil)
 	c.Assert(m.Jobs(), DeepEquals, []state.MachineJob{state.JobHostUnits, state.JobManageEnviron})
 	instanceId, ok := m.InstanceId()
 	c.Assert(ok, Equals, true)
-	c.Assert(instanceId, Equals, state.InstanceId("i-mindustrious"))
+	c.Assert(instanceId, Equals, instance.Id("i-mindustrious"))
 	mcons, err := m.Constraints()
 	c.Assert(err, IsNil)
 	c.Assert(cons, DeepEquals, mcons)
@@ -333,7 +334,7 @@
 
 func (s *StateSuite) TestAddContainerToInjectedMachine(c *C) {
 	oneJob := []state.MachineJob{state.JobHostUnits}
-	m0, err := s.State.InjectMachine("series", emptyCons, state.InstanceId("i-mindustrious"), state.JobHostUnits, state.JobManageEnviron)
+	m0, err := s.State.InjectMachine("series", emptyCons, instance.Id("i-mindustrious"), state.JobHostUnits, state.JobManageEnviron)
 	c.Assert(err, IsNil)
 
 	// Add first container.
@@ -397,7 +398,7 @@
 	for i := 0; i < numInserts; i++ {
 		m, err := s.State.AddMachine("series", state.JobHostUnits)
 		c.Assert(err, IsNil)
-		err = m.SetProvisioned(state.InstanceId(fmt.Sprintf("foo-%d", i)), "fake_nonce")
+		err = m.SetProvisioned(instance.Id(fmt.Sprintf("foo-%d", i)), "fake_nonce")
 		c.Assert(err, IsNil)
 		err = m.SetAgentTools(newTools("7.8.9-foo-bar", "http://arble.tgz"))
 		c.Assert(err, IsNil)
@@ -772,7 +773,7 @@
 	// Dying machine...
 	dying, err := s.State.AddMachine("series", state.JobHostUnits)
 	c.Assert(err, IsNil)
-	err = dying.SetProvisioned(state.InstanceId("i-blah"), "fake-nonce")
+	err = dying.SetProvisioned(instance.Id("i-blah"), "fake-nonce")
 	c.Assert(err, IsNil)
 	err = dying.Destroy()
 	c.Assert(err, IsNil)
@@ -820,7 +821,7 @@
 	s.assertChange(c, w, "0")
 
 	// Change the machine: not reported.
-	err = machine.SetProvisioned(state.InstanceId("i-blah"), "fake-nonce")
+	err = machine.SetProvisioned(instance.Id("i-blah"), "fake-nonce")
 	c.Assert(err, IsNil)
 	s.assertNoChange(c, w)
 
 
=== modified file 'worker/firewaller/firewaller.go'
--- worker/firewaller/firewaller.go	2013-06-11 02:15:31 +0000
+++ worker/firewaller/firewaller.go	2013-06-17 21:39:25 +0000
@@ -8,6 +8,7 @@
 	"launchpad.net/juju-core/environs"
 	"launchpad.net/juju-core/environs/config"
 	"launchpad.net/juju-core/errors"
+	"launchpad.net/juju-core/instance"
 	"launchpad.net/juju-core/log"
 	"launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/state/api/params"
@@ -273,7 +274,7 @@
 		if !ok {
 			return errors.NotFoundf("instance id for %v", m)
 		}
-		instances, err := fw.environ.Instances([]state.InstanceId{instanceId})
+		instances, err := fw.environ.Instances([]instance.Id{instanceId})
 		if err == environs.ErrNoInstances {
 			return nil
 		} else if err != nil {
@@ -444,7 +445,7 @@
 	if !ok {
 		return errors.NotFoundf("instance id for %v", m)
 	}
-	instances, err := fw.environ.Instances([]state.InstanceId{instanceId})
+	instances, err := fw.environ.Instances([]instance.Id{instanceId})
 	if err != nil {
 		return err
 	}
 
=== modified file 'worker/provisioner/provisioner_task.go'
--- worker/provisioner/provisioner_task.go	2013-06-14 01:02:53 +0000
+++ worker/provisioner/provisioner_task.go	2013-06-17 21:39:25 +0000
@@ -68,7 +68,7 @@
 	apiInfo        *api.Info
 
 	// instance id -> instance
-	instances map[state.InstanceId]instance.Instance
+	instances map[instance.Id]instance.Instance
 	// machine id -> machine
 	machines map[string]*state.Machine
 }
@@ -159,7 +159,7 @@
 }
 
 func (task *provisionerTask) populateMachineMaps(ids []string) error {
-	task.instances = make(map[state.InstanceId]instance.Instance)
+	task.instances = make(map[instance.Id]instance.Instance)
 
 	instances, err := task.broker.AllInstances()
 	if err != nil {
@@ -240,7 +240,7 @@
 // findUnknownInstances finds instances which are not associated with a machine.
 func (task *provisionerTask) findUnknownInstances() ([]instance.Instance, error) {
 	// Make a copy of the instances we know about.
-	instances := make(map[state.InstanceId]instance.Instance)
+	instances := make(map[instance.Id]instance.Instance)
 	for k, v := range task.instances {
 		instances[k] = v
 	}
 
=== modified file 'worker/provisioner/provisioner_test.go'
--- worker/provisioner/provisioner_test.go	2013-06-14 01:23:48 +0000
+++ worker/provisioner/provisioner_test.go	2013-06-17 21:39:25 +0000
@@ -222,7 +222,7 @@
 
 // waitInstanceId waits until the supplied machine has an instance id, then
 // asserts it is as expected.
-func (s *ProvisionerSuite) waitInstanceId(c *C, m *state.Machine, expect state.InstanceId) {
+func (s *ProvisionerSuite) waitInstanceId(c *C, m *state.Machine, expect instance.Id) {
 	s.waitMachine(c, m, func() bool {
 		err := m.Refresh()
 		c.Assert(err, IsNil)