resources: Add NewNamedResource helper

This makes the common pattern of NewResource, SetName, easier. It also
makes it less likely for you to forget to use SetName.

examples/lib/libmgmt1.go

@@ -57,15 +57,13 @@ func (obj *MyGAPI) Graph() (*pgraph.Graph, error) {
 		return nil, fmt.Errorf("libmgmt: MyGAPI is not initialized")
 	}
 
-	// TODO: this method of instantiation is deprecated, use: NewResource
+	n1, err := resources.NewNamedResource("noop", "noop1")
-	n1 := &resources.NoopRes{
+	if err != nil {
-		BaseRes: resources.BaseRes{
+		return nil, err
-			Name:       "noop1",
-			Kind:       "noop",
-			MetaParams: resources.DefaultMetaParams,
-		},
 	}
 
+	// NOTE: This is considered the legacy method to build graphs. Avoid
+	// importing the legacy `yamlgraph` lib if possible for custom graphs.
 	// we can still build a graph via the yaml method
 	gc := &yamlgraph.GraphConfig{
 		Graph: obj.Name,
@@ -74,7 +72,7 @@ func (obj *MyGAPI) Graph() (*pgraph.Graph, error) {
 			Exec:  []*resources.ExecRes{},
 			File:  []*resources.FileRes{},
 			Msg:   []*resources.MsgRes{},
-			Noop:  []*resources.NoopRes{n1},
+			Noop:  []*resources.NoopRes{n1.(*resources.NoopRes)},
 			Pkg:   []*resources.PkgRes{},
 			Svc:   []*resources.SvcRes{},
 			Timer: []*resources.TimerRes{},

examples/lib/libmgmt2.go

@@ -65,11 +65,10 @@ func (obj *MyGAPI) Graph() (*pgraph.Graph, error) {
 	}
 	var vertex pgraph.Vertex
 	for i := uint(0); i < obj.Count; i++ {
-		n, err := resources.NewResource("noop")
+		n, err := resources.NewNamedResource("noop", fmt.Sprintf("noop%d", i))
 		if err != nil {
 			return nil, err
 		}
-		n.SetName(fmt.Sprintf("noop%d", i))
 		g.AddVertex(n)
 		if i > 0 {
 			g.AddEdge(vertex, n, &resources.Edge{Name: fmt.Sprintf("e%d", i)})

hcl/parse.go

@@ -357,14 +357,12 @@ func loadResourcesHcl(list *ast.ObjectList) ([]*Resource, error) {
 			}
 		}
 
-		res, err := resources.NewResource(kind)
+		res, err := resources.NewNamedResource(kind, name)
 		if err != nil {
 			log.Printf("hcl: unable to parse resource: %v", err)
 			return nil, err
 		}
 
-		res.SetName(name)
-
 		if err := hcl.DecodeObject(res, item.Val); err != nil {
 			log.Printf("hcl: unable to decode body: %v", err)
 			return nil, fmt.Errorf(

resources/resources.go

@@ -52,7 +52,8 @@ func RegisterResource(kind string, fn func() Res) {
 	registeredResources[kind] = fn
 }
 
-// NewResource returns an empty resource object from a registered kind.
+// NewResource returns an empty resource object from a registered kind. It
+// errors if the resource kind doesn't exist.
 func NewResource(kind string) (Res, error) {
 	fn, ok := registeredResources[kind]
 	if !ok {
@@ -64,6 +65,21 @@ func NewResource(kind string) (Res, error) {
 	return res, nil
 }
 
+// NewNamedResource returns an empty resource object from a registered kind. It
+// also sets the name. It is a wrapper around NewResource. It also errors if the
+// name is empty.
+func NewNamedResource(kind, name string) (Res, error) {
+	if name == "" {
+		return nil, fmt.Errorf("resource name is empty")
+	}
+	res, err := NewResource(kind)
+	if err != nil {
+		return nil, err
+	}
+	res.SetName(name)
+	return res, nil
+}
+
 //go:generate stringer -type=ResState -output=resstate_stringer.go
 
 // The ResState type represents the current activity state of each resource.

resources/util_test.go

@@ -44,18 +44,12 @@ func TestSort0(t *testing.T) {
 }
 
 func TestSort1(t *testing.T) {
-	r1, _ := NewResource("noop")
+	r1, _ := NewNamedResource("noop", "noop1")
-	r1.SetName("noop1")
+	r2, _ := NewNamedResource("noop", "noop2")
-	r2, _ := NewResource("noop")
+	r3, _ := NewNamedResource("noop", "noop3")
-	r2.SetName("noop2")
+	r4, _ := NewNamedResource("noop", "noop4")
-	r3, _ := NewResource("noop")
+	r5, _ := NewNamedResource("noop", "noop5")
-	r3.SetName("noop3")
+	r6, _ := NewNamedResource("noop", "noop6")
-	r4, _ := NewResource("noop")
-	r4.SetName("noop4")
-	r5, _ := NewResource("noop")
-	r5.SetName("noop5")
-	r6, _ := NewResource("noop")
-	r6.SetName("noop6")
 
 	rs := []Res{r3, r2, r6, r1, r5, r4}
 	s := Sort(rs)
@@ -124,7 +118,11 @@ func TestMiscEncodeDecode2(t *testing.T) {
 	var err error
 
 	// encode
-	input, _ := NewResource("file")
+	input, err := NewNamedResource("file", "file1")
+	if err != nil {
+		t.Errorf("Can't create: %v", err)
+		return
+	}
 
 	b64, err := ResToB64(input)
 	if err != nil {

test/shell/libmgmt-change1.go

@@ -62,11 +62,10 @@ func (obj *MyGAPI) Graph() (*pgraph.Graph, error) {
 		return nil, err
 	}
 
-	n0, err := resources.NewResource("noop")
+	n0, err := resources.NewNamedResource("noop", "noop1")
 	if err != nil {
 		return nil, err
 	}
-	n0.SetName("noop1")
 	g.AddVertex(n0)
 
 	//g, err := config.NewGraphFromConfig(obj.data.Hostname, obj.data.World, obj.data.Noop)

test/shell/libmgmt-change2.go

@@ -69,28 +69,25 @@ func (obj *MyGAPI) Graph() (*pgraph.Graph, error) {
 	}
 
 	if !obj.flipflop {
-		n0, err := resources.NewResource("noop")
+		n0, err := resources.NewNamedResource("noop", "noop0")
 		if err != nil {
 			return nil, err
 		}
-		n0.SetName("noop0")
 		g.AddVertex(n0)
 
 	} else {
 		// NOTE: these will get autogrouped
-		n1, err := resources.NewResource("noop")
+		n1, err := resources.NewNamedResource("noop", "noop1")
 		if err != nil {
 			return nil, err
 		}
-		n1.SetName("noop1")
 		n1.Meta().AutoGroup = obj.autoGroup // enable or disable it
 		g.AddVertex(n1)
 
-		n2, err := resources.NewResource("noop")
+		n2, err := resources.NewNamedResource("noop", "noop2")
 		if err != nil {
 			return nil, err
 		}
-		n2.SetName("noop2")
 		n2.Meta().AutoGroup = obj.autoGroup // enable or disable it
 		g.AddVertex(n2)
 	}

test/test-examples.sh

@@ -36,7 +36,7 @@ rmdir "$tmpdir"	# cleanup
 
 if [[ -n "$failures" ]]; then
 	echo 'FAIL'
-	echo 'The following tests have failed:'
+	echo "The following tests (in: ${linkto}) have failed:"
 	echo -e "$failures"
 	exit 1
 fi