Reviewers: mp+220215_code.launchpad.net,

Message:
Please take a look.

Description:
state/apiserver/common: StringResource

This adds a new resource type: common.StringResource. It just lets us
register "dataDir" as a Resource, instead of having to give Client
secret insight into attributes of the srvRoot object. That brings us
closer to having all of the Facades all part of a simple Registry
instead of having special cases.

https://code.launchpad.net/~jameinel/juju-core/api-named-resources-datadir/+merge/220215

Requires:
https://code.launchpad.net/~jameinel/juju-core/api-named-resources/+merge/220208

(do not edit description out of merge proposal)


Please review this at https://codereview.appspot.com/99410043/

Affected files (+37, -6 lines):
   A [revision details]
   M state/apiserver/client/client.go
   M state/apiserver/client/run.go
   M state/apiserver/common/resource.go
   M state/apiserver/common/resource_test.go
   M state/apiserver/root.go


Index: [revision details]
=== added file '[revision details]'
--- [revision details]	2012-01-01 00:00:00 +0000
+++ [revision details]	2012-01-01 00:00:00 +0000
@@ -0,0 +1,2 @@
+Old revision: <email address hidden>
+New revision: <email address hidden>

Index: state/apiserver/root.go
=== modified file 'state/apiserver/root.go'
--- state/apiserver/root.go	2014-05-20 08:17:21 +0000
+++ state/apiserver/root.go	2014-05-20 09:42:11 +0000
@@ -73,7 +73,8 @@
  		resources: common.NewResources(),
  		entity:    entity,
  	}
-	r.clientAPI.API = client.NewAPI(r.srv.state, r.resources, r,  
r.srv.dataDir)
+	r.resources.RegisterNamed("dataDir", common.StringResource(r.srv.dataDir))
+	r.clientAPI.API = client.NewAPI(r.srv.state, r.resources, r)
  	return r
  }



Index: state/apiserver/client/client.go
=== modified file 'state/apiserver/client/client.go'
--- state/apiserver/client/client.go	2014-05-13 04:50:10 +0000
+++ state/apiserver/client/client.go	2014-05-20 09:42:11 +0000
@@ -36,7 +36,6 @@
  	auth      common.Authorizer
  	resources *common.Resources
  	client    *Client
-	dataDir   string
  	// statusSetter provides common methods for updating an entity's  
provisioning status.
  	statusSetter *common.StatusSetter
  }
@@ -47,12 +46,11 @@
  }

  // NewAPI creates a new instance of the Client API.
-func NewAPI(st *state.State, resources *common.Resources, authorizer  
common.Authorizer, datadir string) *API {
+func NewAPI(st *state.State, resources *common.Resources, authorizer  
common.Authorizer) *API {
  	r := &API{
  		state:        st,
  		auth:         authorizer,
  		resources:    resources,
-		dataDir:      datadir,
  		statusSetter: common.NewStatusSetter(st, common.AuthAlways(true)),
  	}
  	r.client = &Client{


Index: state/apiserver/client/run.go
=== modified file 'state/apiserver/client/run.go'
--- state/apiserver/client/run.go	2014-04-23 08:50:28 +0000
+++ state/apiserver/client/run.go	2014-05-20 09:42:11 +0000
@@ -14,6 +14,7 @@
  	"launchpad.net/juju-core/instance"
  	"launchpad.net/juju-core/state"
  	"launchpad.net/juju-core/state/api/params"
+	"launchpad.net/juju-core/state/apiserver/common"
  	"launchpad.net/juju-core/utils"
  	"launchpad.net/juju-core/utils/set"
  	"launchpad.net/juju-core/utils/ssh"
@@ -75,6 +76,14 @@
  	return result, nil
  }

+func (c *Client) getDataDir() string {
+	dataResource, ok := c.api.resources.Get("dataDir").(common.StringResource)
+	if !ok {
+		return ""
+	}
+	return dataResource.String()
+}
+
  // Run the commands specified on the machines identified through the
  // list of machines, units and services.
  func (c *Client) Run(run params.RunParams) (results params.RunResults, err  
error) {
@@ -110,7 +119,7 @@
  		execParam := remoteParamsForMachine(machine, command, run.Timeout)
  		params = append(params, execParam)
  	}
-	return ParallelExecute(c.api.dataDir, params), nil
+	return ParallelExecute(c.getDataDir(), params), nil
  }

  // RunOnAllMachines attempts to run the specified command on all the  
machines.
@@ -125,7 +134,7 @@
  	for _, machine := range machines {
  		params = append(params, remoteParamsForMachine(machine, command,  
run.Timeout))
  	}
-	return ParallelExecute(c.api.dataDir, params), nil
+	return ParallelExecute(c.getDataDir(), params), nil
  }

  // RemoteExec extends the standard ssh.ExecParams by providing the machine  
and


Index: state/apiserver/common/resource.go
=== modified file 'state/apiserver/common/resource.go'
--- state/apiserver/common/resource.go	2014-05-20 06:20:06 +0000
+++ state/apiserver/common/resource.go	2014-05-20 09:42:11 +0000
@@ -111,3 +111,15 @@
  	defer rs.mu.Unlock()
  	return len(rs.resources)
  }
+
+// StringResource is just a regular 'string' that matches the Resource
+// interface.
+type StringResource string
+
+func (StringResource) Stop() error {
+	return nil
+}
+
+func (s StringResource) String() string {
+	return string(s)
+}


Index: state/apiserver/common/resource_test.go
=== modified file 'state/apiserver/common/resource_test.go'
--- state/apiserver/common/resource_test.go	2014-05-20 06:20:06 +0000
+++ state/apiserver/common/resource_test.go	2014-05-20 09:42:11 +0000
@@ -147,3 +147,12 @@

  	c.Assert(rs.Count(), gc.Equals, 0)
  }
+
+func (resourceSuite) TestStringResource(c *gc.C) {
+	rs := common.NewResources()
+	r1 := common.StringResource("foobar")
+	id := rs.Register(r1)
+	c.Check(rs.Get(id), gc.Equals, r1)
+	asStr := rs.Get(id).(common.StringResource).String()
+	c.Check(asStr, gc.Equals, "foobar")
+}