rpc: add Refresh method

rpc/resource_provider.go

@@ -87,6 +87,20 @@ func (p *ResourceProvider) Diff(
 	return resp.Diff, err
 }
 
+func (p *ResourceProvider) Refresh(
+	s *terraform.ResourceState) (*terraform.ResourceState, error) {
+	var resp ResourceProviderRefreshResponse
+	err := p.Client.Call(p.Name+".Refresh", s, &resp)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Error != nil {
+		err = resp.Error
+	}
+
+	return resp.State, err
+}
+
 func (p *ResourceProvider) Resources() []terraform.ResourceType {
 	var result []terraform.ResourceType
 
@@ -129,6 +143,11 @@ type ResourceProviderDiffResponse struct {
 	Error *BasicError
 }
 
+type ResourceProviderRefreshResponse struct {
+	State *terraform.ResourceState
+	Error *BasicError
+}
+
 type ResourceProviderValidateArgs struct {
 	Config *terraform.ResourceConfig
 }
@@ -185,6 +204,17 @@ func (s *ResourceProviderServer) Diff(
 	return nil
 }
 
+func (s *ResourceProviderServer) Refresh(
+	state *terraform.ResourceState,
+	result *ResourceProviderRefreshResponse) error {
+	newState, err := s.Provider.Refresh(state)
+	*result = ResourceProviderRefreshResponse{
+		State: newState,
+		Error: NewBasicError(err),
+	}
+	return nil
+}
+
 func (s *ResourceProviderServer) Resources(
 	nothing interface{},
 	result *[]terraform.ResourceType) error {

rpc/resource_provider_test.go

@@ -192,6 +192,36 @@ func TestResourceProvider_diff_error(t *testing.T) {
 	}
 }
 
+func TestResourceProvider_refresh(t *testing.T) {
+	p := new(terraform.MockResourceProvider)
+	client, server := testClientServer(t)
+	name, err := Register(server, p)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	provider := &ResourceProvider{Client: client, Name: name}
+
+	p.RefreshReturn = &terraform.ResourceState{
+		ID: "bob",
+	}
+
+	// Refresh
+	state := &terraform.ResourceState{}
+	newState, err := provider.Refresh(state)
+	if !p.RefreshCalled {
+		t.Fatal("refresh should be called")
+	}
+	if !reflect.DeepEqual(p.RefreshState, state) {
+		t.Fatalf("bad: %#v", p.RefreshState)
+	}
+	if err != nil {
+		t.Fatalf("bad: %#v", err)
+	}
+	if !reflect.DeepEqual(p.RefreshReturn, newState) {
+		t.Fatalf("bad: %#v", newState)
+	}
+}
+
 func TestResourceProvider_resources(t *testing.T) {
 	p := new(terraform.MockResourceProvider)
 	client, server := testClientServer(t)