rpc: Make a Register function to make working with easier

rpc/resource_provider.go

@@ -8,11 +8,12 @@ import (
 
 type ResourceProvider struct {
 	Client *rpc.Client
+	Name   string
 }
 
 func (p *ResourceProvider) Configure(c map[string]interface{}) ([]string, error) {
 	var resp ResourceProviderConfigureResponse
-	err := p.Client.Call("ResourceProvider.Configure", c, &resp)
+	err := p.Client.Call(p.Name+".Configure", c, &resp)
 	if err != nil {
 		return nil, err
 	}

rpc/resource_provider_test.go

@@ -10,11 +10,11 @@ import (
 func TestResourceProvider_configure(t *testing.T) {
 	p := new(terraform.MockResourceProvider)
 	client, server := testClientServer(t)
-	server.RegisterName("ResourceProvider", &ResourceProviderServer{
-		Provider: p,
-	})
-
-	provider := &ResourceProvider{Client: client}
+	name, err := Register(server, p)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	provider := &ResourceProvider{Client: client, Name: name}
 
 	// Configure
 	config := map[string]interface{}{"foo": "bar"}

rpc/rpc.go

@@ -0,0 +1,32 @@
+package rpc
+
+import (
+	"errors"
+	"fmt"
+	"net/rpc"
+	"sync"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// nextId is the next ID to use for names registered.
+var nextId uint32 = 0
+var nextLock sync.Mutex
+
+// Register registers a Terraform thing with the RPC server and returns
+// the name it is registered under.
+func Register(server *rpc.Server, thing interface{}) (name string, err error) {
+	nextLock.Lock()
+	defer nextLock.Unlock()
+
+	switch t := thing.(type) {
+	case terraform.ResourceProvider:
+		name = fmt.Sprintf("Terraform%d", nextId)
+		err = server.RegisterName(name, &ResourceProviderServer{Provider: t})
+	default:
+		return "", errors.New("Unknown type to register for RPC server.")
+	}
+
+	nextId += 1
+	return
+}