add utility method to list installed plugins by index

internal/installation/util.go

@@ -22,24 +22,52 @@ import (
 
 	"sigs.k8s.io/krew/internal/installation/receipt"
 	"sigs.k8s.io/krew/pkg/constants"
+	"sigs.k8s.io/krew/pkg/index"
 )
 
 // ListInstalledPlugins returns a list of all install plugins in a
 // name:version format based on the install receipts at the specified dir.
 func ListInstalledPlugins(receiptsDir string) (map[string]string, error) {
-	matches, err := filepath.Glob(filepath.Join(receiptsDir, "*"+constants.ManifestExtension))
+	installed := make(map[string]string)
+	receipts, err := getInstalledPluginReceipts(receiptsDir)
 	if err != nil {
-		return nil, errors.Wrapf(err, "failed to grab receipts directory (%s) for manifests", receiptsDir)
+		return nil, err
 	}
-	klog.V(4).Infof("Found %d install receipts in %s", len(matches), receiptsDir)
-	installed := make(map[string]string)
-	for _, m := range matches {
-		r, err := receipt.Load(m)
+	for _, r := range receipts {
+		installed[r.GetObjectMeta().GetName()] = r.Spec.Version
+	}
+	return installed, nil
+}
+
+// InstalledPluginsFromIndex returns a list of all install plugins from a particular index.
+func InstalledPluginsFromIndex(receiptsDir, indexName string) ([]index.Receipt, error) {
+	var out []index.Receipt
+	receipts, err := getInstalledPluginReceipts(receiptsDir)
+	if err != nil {
+		return nil, err
+	}
+	for _, r := range receipts {
+		if r.Status.Source.Name == indexName {
+			out = append(out, r)
+		}
+	}
+	return out, nil
+}
+
+func getInstalledPluginReceipts(receiptsDir string) ([]index.Receipt, error) {
+	files, err := filepath.Glob(filepath.Join(receiptsDir, "*"+constants.ManifestExtension))
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to glob receipts directory (%s) for manifests", receiptsDir)
+	}
+	out := make([]index.Receipt, 0, len(files))
+	for _, f := range files {
+		r, err := receipt.Load(f)
 		if err != nil {
-			return nil, errors.Wrapf(err, "failed to parse plugin install receipt %s", m)
+			return nil, errors.Wrapf(err, "failed to parse plugin install receipt %s", f)
 		}
+		out = append(out, r)
 		klog.V(4).Infof("parsed receipt for %s: version=%s", r.GetObjectMeta().GetName(), r.Spec.Version)
-		installed[r.GetObjectMeta().GetName()] = r.Spec.Version
+
 	}
-	return installed, nil
+	return out, nil
 }

internal/installation/util_test.go

@@ -80,3 +80,35 @@ func TestListInstalledPlugins(t *testing.T) {
 		})
 	}
 }
+
+func TestInstalledPluginsFromIndex(t *testing.T) {
+	tempDir, cleanup := testutil.NewTempDir(t)
+	defer cleanup()
+
+	indexA := index.ReceiptStatus{Source: index.SourceIndex{Name: "a"}}
+	var indexNone index.ReceiptStatus
+
+	for _, testReceipt := range []index.Receipt{
+		testutil.NewReceipt().WithPlugin(testutil.NewPlugin().WithName("a1").V()).WithStatus(indexA).V(),
+		testutil.NewReceipt().WithPlugin(testutil.NewPlugin().WithName("a2").V()).WithStatus(indexA).V(),
+		testutil.NewReceipt().WithPlugin(testutil.NewPlugin().WithName("default1").V()).WithStatus(indexNone).V(),
+	} {
+		tempDir.WriteYAML(testReceipt.Name+constants.ManifestExtension, testReceipt)
+	}
+
+	v, err := InstalledPluginsFromIndex(tempDir.Root(), "a")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if expected, got := 2, len(v); expected != got {
+		t.Fatalf("expected %d, got: %d for index 'a'", expected, got)
+	}
+
+	v, err = InstalledPluginsFromIndex(tempDir.Root(), constants.DefaultIndexName)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if expected, got := 1, len(v); expected != got {
+		t.Fatalf("expected %d, got: %d for index 'a'", expected, got)
+	}
+}