Merge pull request #7605 from wallyworld/cmr-controller-addr-lookup

Look for offer model uuid in local controller first

## Description of change

When setting up a cross model relation, the api address of the host controller needs to be determined. This PR ensures that we first look for the model in the local controller before looking for any external controllers.

## QA steps

Deploy a cmr scenario with just one controller.

apiserver/common/controllerconfig.go

@@ -4,6 +4,7 @@
 package common
 
 import (
+	"github.com/juju/errors"
 	"gopkg.in/juju/names.v2"
 
 	"github.com/juju/juju/apiserver/params"
@@ -49,13 +50,13 @@ func (s *ControllerConfigAPI) ControllerAPIInfoForModels(args params.Entities) (
 			result.Results[i].Error = ServerError(err)
 			continue
 		}
-		ec, err := s.st.ControllerInfo(modelTag.Id())
+		addrs, CACert, err := s.st.ControllerInfo(modelTag.Id())
 		if err != nil {
 			result.Results[i].Error = ServerError(err)
 			continue
 		}
-		result.Results[i].Addresses = ec.ControllerInfo().Addrs
-		result.Results[i].CACert = ec.ControllerInfo().CACert
+		result.Results[i].Addresses = addrs
+		result.Results[i].CACert = CACert
 	}
 	return result, nil
 }
@@ -65,7 +66,25 @@ type controllerStateShim struct {
 }
 
 // ControllerInfo returns the external controller details for the specified model.
-func (s *controllerStateShim) ControllerInfo(modelUUID string) (state.ExternalController, error) {
+func (s *controllerStateShim) ControllerInfo(modelUUID string) (addrs []string, CACert string, _ error) {
+	// First see if the requested model UUID is hosted by this controller.
+	_, err := s.State.GetModel(names.NewModelTag(modelUUID))
+	if err != nil && !errors.IsNotFound(err) {
+		return nil, "", errors.Trace(err)
+	}
+	if err == nil {
+		addr, err := apiAddresses(s.State)
+		if err != nil {
+			return nil, "", errors.Trace(err)
+		}
+		return addr, s.State.CACert(), nil
+	}
+
+	// Now check any external controllers.
 	ec := state.NewExternalControllers(s.State)
-	return ec.ControllerForModel(modelUUID)
+	info, err := ec.ControllerForModel(modelUUID)
+	if err != nil {
+		return nil, "", errors.Trace(err)
+	}
+	return info.ControllerInfo().Addrs, info.ControllerInfo().CACert, nil
 }

apiserver/common/controllerconfig_test.go

@@ -7,12 +7,17 @@ import (
 	"fmt"
 
 	jc "github.com/juju/testing/checkers"
+	"github.com/juju/utils"
 	gc "gopkg.in/check.v1"
+	"gopkg.in/juju/names.v2"
 
 	"github.com/juju/errors"
 	"github.com/juju/juju/apiserver/common"
+	"github.com/juju/juju/apiserver/params"
 	"github.com/juju/juju/controller"
+	"github.com/juju/juju/core/crossmodel"
 	"github.com/juju/juju/environs/config"
+	jujutesting "github.com/juju/juju/juju/testing"
 	"github.com/juju/juju/provider/dummy"
 	"github.com/juju/juju/state"
 	"github.com/juju/juju/testing"
@@ -42,8 +47,11 @@ func (f *fakeControllerAccessor) ControllerConfig() (controller.Config, error) {
 	}, nil
 }
 
-func (f *fakeControllerAccessor) ControllerInfo(modelUUID string) (state.ExternalController, error) {
-	return nil, errors.NotImplementedf("ControllerInfo")
+func (f *fakeControllerAccessor) ControllerInfo(modelUUID string) ([]string, string, error) {
+	if modelUUID != testing.ModelTag.Id() {
+		return nil, "", errors.New("wrong model")
+	}
+	return []string{"192.168.1.1:17070"}, testing.CACert, nil
 }
 
 func (s *controllerConfigSuite) TearDownTest(c *gc.C) {
@@ -74,3 +82,63 @@ func (*controllerConfigSuite) TestControllerConfigFetchError(c *gc.C) {
 	_, err := cc.ControllerConfig()
 	c.Assert(err, gc.ErrorMatches, "pow")
 }
+
+func (*controllerConfigSuite) TestControllerInfo(c *gc.C) {
+	cc := common.NewControllerConfig(
+		&fakeControllerAccessor{},
+	)
+	results, err := cc.ControllerAPIInfoForModels(params.Entities{
+		Entities: []params.Entity{{Tag: testing.ModelTag.String()}}})
+	c.Assert(err, jc.ErrorIsNil)
+	c.Assert(results.Results, gc.HasLen, 1)
+	c.Assert(results.Results[0].Addresses, gc.DeepEquals, []string{"192.168.1.1:17070"})
+	c.Assert(results.Results[0].CACert, gc.Equals, testing.CACert)
+}
+
+type controllerInfoSuite struct {
+	jujutesting.JujuConnSuite
+
+	localModel *state.State
+}
+
+var _ = gc.Suite(&controllerInfoSuite{})
+
+func (s *controllerInfoSuite) SetUpTest(c *gc.C) {
+	s.JujuConnSuite.SetUpTest(c)
+	s.localModel = s.Factory.MakeModel(c, nil)
+	s.AddCleanup(func(*gc.C) {
+		s.localModel.Close()
+	})
+}
+
+func (s *controllerInfoSuite) TestControllerInfoLocalModel(c *gc.C) {
+	cc := common.NewStateControllerConfig(s.State)
+	results, err := cc.ControllerAPIInfoForModels(params.Entities{
+		Entities: []params.Entity{{Tag: s.localModel.ModelTag().String()}}})
+	c.Assert(err, jc.ErrorIsNil)
+	c.Assert(results.Results, gc.HasLen, 1)
+	apiAddr, err := s.State.APIHostPorts()
+	c.Assert(err, jc.ErrorIsNil)
+	c.Assert(results.Results[0].Addresses, gc.HasLen, 1)
+	c.Assert(results.Results[0].Addresses[0], gc.Equals, apiAddr[0][0].String())
+	c.Assert(results.Results[0].CACert, gc.Equals, s.State.CACert())
+}
+
+func (s *controllerInfoSuite) TestControllerInfoExternalModel(c *gc.C) {
+	ec := state.NewExternalControllers(s.State)
+	modelUUID := utils.MustNewUUID().String()
+	info := crossmodel.ControllerInfo{
+		ControllerTag: testing.ControllerTag,
+		Addrs:         []string{"192.168.1.1:12345"},
+		CACert:        testing.CACert,
+	}
+	_, err := ec.Save(info, modelUUID)
+	c.Assert(err, jc.ErrorIsNil)
+	cc := common.NewStateControllerConfig(s.State)
+	results, err := cc.ControllerAPIInfoForModels(params.Entities{
+		Entities: []params.Entity{{Tag: names.NewModelTag(modelUUID).String()}}})
+	c.Assert(err, jc.ErrorIsNil)
+	c.Assert(results.Results, gc.HasLen, 1)
+	c.Assert(results.Results[0].Addresses, gc.DeepEquals, info.Addrs)
+	c.Assert(results.Results[0].CACert, gc.Equals, info.CACert)
+}

apiserver/firewaller/mock_test.go

@@ -72,11 +72,11 @@ func (st *mockState) ControllerConfig() (controller.Config, error) {
 	return nil, errors.NotImplementedf("ControllerConfig")
 }
 
-func (st *mockState) ControllerInfo(modelUUID string) (state.ExternalController, error) {
+func (st *mockState) ControllerInfo(modelUUID string) ([]string, string, error) {
 	if info, ok := st.controllerInfo[modelUUID]; !ok {
-		return nil, errors.NotFoundf("controller info for %v", modelUUID)
+		return nil, "", errors.NotFoundf("controller info for %v", modelUUID)
 	} else {
-		return info, nil
+		return info.ControllerInfo().Addrs, info.ControllerInfo().CACert, nil
 	}
 }
 

apiserver/remoterelations/mock_test.go

@@ -53,11 +53,11 @@ func (st *mockState) ControllerConfig() (controller.Config, error) {
 	return nil, errors.NotImplementedf("ControllerConfig")
 }
 
-func (st *mockState) ControllerInfo(modelUUID string) (state.ExternalController, error) {
+func (st *mockState) ControllerInfo(modelUUID string) ([]string, string, error) {
 	if info, ok := st.controllerInfo[modelUUID]; !ok {
-		return nil, errors.NotFoundf("controller info for %v", modelUUID)
+		return nil, "", errors.NotFoundf("controller info for %v", modelUUID)
 	} else {
-		return info, nil
+		return info.ControllerInfo().Addrs, info.ControllerInfo().CACert, nil
 	}
 }
 

state/interface.go

@@ -103,7 +103,7 @@ type ModelAccessor interface {
 // access controller information.
 type ControllerAccessor interface {
 	ControllerConfig() (controller.Config, error)
-	ControllerInfo(modelUUID string) (ExternalController, error)
+	ControllerInfo(modelUUID string) (addrs []string, CACert string, _ error)
 }
 
 // UnitsWatcher defines the methods needed to retrieve an entity (a