Add tests for filtering.

app/router.go

@@ -164,8 +164,8 @@ var topologyRegistry = map[string]topologyView{
 		parent:   "containers",
 		renderer: render.ContainerImageRenderer,
 		options: optionParams{"system": {
-			{"show", "Show system containers", true, nop},
-			{"hide", "Hide system containers", false, render.FilterSystem},
+			{"show", "Show system containers", false, nop},
+			{"hide", "Hide system containers", true, render.FilterSystem},
 		}},
 	},
 	"hosts": {

render/render.go

@@ -172,14 +172,14 @@ func ColorConnected(r Renderer) Renderer {
 // Filter removes nodes from a view based on a predicate.
 type Filter struct {
 	Renderer
-	f func(RenderableNode) bool
+	FilterFunc func(RenderableNode) bool
 }
 
 // Render implements Renderer
 func (f Filter) Render(rpt report.Report) RenderableNodes {
 	output := RenderableNodes{}
 	for id, node := range f.Renderer.Render(rpt) {
-		if f.f(node) {
+		if f.FilterFunc(node) {
 			output[id] = node
 		}
 	}
@@ -207,7 +207,7 @@ const IsConnected = "is_connected"
 func FilterUnconnected(r Renderer) Renderer {
 	return Filter{
 		Renderer: ColorConnected(r),
-		f: func(node RenderableNode) bool {
+		FilterFunc: func(node RenderableNode) bool {
 			_, ok := node.Metadata[IsConnected]
 			return ok
 		},
@@ -218,7 +218,7 @@ func FilterUnconnected(r Renderer) Renderer {
 func FilterSystem(r Renderer) Renderer {
 	return Filter{
 		Renderer: r,
-		f: func(node RenderableNode) bool {
+		FilterFunc: func(node RenderableNode) bool {
 			containerName := node.Metadata[docker.ContainerName]
 			if _, ok := systemContainerNames[containerName]; ok {
 				return false

render/render_test.go

@@ -187,7 +187,29 @@ func TestFilterRender(t *testing.T) {
 	}
 	have := expected.Sterilize(renderer.Render(report.MakeReport()))
 	if !reflect.DeepEqual(want, have) {
-		t.Errorf("want %+v, have %+v", want, have)
+		t.Error(test.Diff(want, have))
+	}
+}
+
+func TestFilterRender2(t *testing.T) {
+	// Test adjacencies are removed for filtered nodes.
+	renderer := render.Filter{
+		FilterFunc: func(node render.RenderableNode) bool {
+			return node.ID != "bar"
+		},
+		Renderer: mockRenderer{RenderableNodes: render.RenderableNodes{
+			"foo": {ID: "foo", Node: report.MakeNode().WithAdjacent("bar")},
+			"bar": {ID: "bar", Node: report.MakeNode().WithAdjacent("foo")},
+			"baz": {ID: "baz", Node: report.MakeNode()},
+		}},
+	}
+	want := render.RenderableNodes{
+		"foo": {ID: "foo", Node: report.MakeNode()},
+		"baz": {ID: "baz", Node: report.MakeNode()},
+	}
+	have := expected.Sterilize(renderer.Render(report.MakeReport()))
+	if !reflect.DeepEqual(want, have) {
+		t.Error(test.Diff(want, have))
 	}
 }
 

render/renderable_node.go

@@ -125,6 +125,15 @@ func (rn RenderableNode) Copy() RenderableNode {
 // RenderableNodes is a set of RenderableNodes
 type RenderableNodes map[string]RenderableNode
 
+// Copy produces a deep copy of the RenderableNodes
+func (rns RenderableNodes) Copy() RenderableNodes {
+	result := RenderableNodes{}
+	for key, value := range rns {
+		result[key] = value.Copy()
+	}
+	return result
+}
+
 // Merge merges two sets of RenderableNodes, returning a new set.
 func (rns RenderableNodes) Merge(other RenderableNodes) RenderableNodes {
 	result := RenderableNodes{}

render/topologies.go

@@ -85,7 +85,7 @@ var ContainerRenderer = MakeReduce(
 		// but we need to be careful to ensure we only include each edge once, by only
 		// including the ProcessRenderer once.
 		Renderer: Filter{
-			f: func(n RenderableNode) bool {
+			FilterFunc: func(n RenderableNode) bool {
 				_, inContainer := n.Node.Metadata[docker.ContainerID]
 				_, isConnected := n.Node.Metadata[IsConnected]
 				return inContainer || isConnected

render/topologies_test.go

@@ -4,6 +4,7 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/weaveworks/scope/probe/docker"
 	"github.com/weaveworks/scope/render"
 	"github.com/weaveworks/scope/render/expected"
 	"github.com/weaveworks/scope/test"
@@ -33,6 +34,19 @@ func TestContainerRenderer(t *testing.T) {
 	}
 }
 
+func TestContainerFilterRenderer(t *testing.T) {
+	// tag on of the containers in the topology and ensure
+	// it is filtered out correctly.
+	input := test.Report.Copy()
+	input.Container.Nodes[test.ClientContainerNodeID].Metadata[docker.LabelPrefix+"works.weave.role"] = "system"
+	have := expected.Sterilize(render.FilterSystem(render.ContainerRenderer).Render(input))
+	want := expected.RenderedContainers.Copy()
+	delete(want, test.ClientContainerID)
+	if !reflect.DeepEqual(want, have) {
+		t.Error(test.Diff(want, have))
+	}
+}
+
 func TestContainerImageRenderer(t *testing.T) {
 	have := expected.Sterilize(render.ContainerImageRenderer.Render(test.Report))
 	want := expected.RenderedContainerImages