database: add ability to list namespaces

database/database.go

@@ -37,6 +37,9 @@ var (
 )
 
 type Datastore interface {
+	// Namespace
+	ListNamespaces() ([]Namespace, error)
+
 	// Layer
 	InsertLayer(Layer) error
 	FindLayer(name string, withFeatures, withVulnerabilities bool) (Layer, error)

database/pgsql/namespace.go

@@ -49,3 +49,27 @@ func (pgSQL *pgSQL) insertNamespace(namespace database.Namespace) (int, error) {
 
 	return id, nil
 }
+
+func (pgSQL *pgSQL) ListNamespaces() (namespaces []database.Namespace, err error) {
+	rows, err := pgSQL.Query(getQuery("l_namespace"))
+	if err != nil {
+		return namespaces, handleError("l_namespace", err)
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var namespace database.Namespace
+
+		err = rows.Scan(&namespace.ID, &namespace.Name)
+		if err != nil {
+			return namespaces, handleError("l_namespace.Scan()", err)
+		}
+
+		namespaces = append(namespaces, namespace)
+	}
+	if err = rows.Err(); err != nil {
+		return namespaces, handleError("l_namespace.Rows()", err)
+	}
+
+	return namespaces, err
+}

database/pgsql/namespace_test.go

@@ -16,7 +16,8 @@ package pgsql
 
 import (
 	"testing"
-
+  "fmt"
+
 	"github.com/coreos/clair/database"
 	"github.com/stretchr/testify/assert"
 )
@@ -41,3 +42,25 @@ func TestInsertNamespace(t *testing.T) {
 	assert.Nil(t, err)
 	assert.Equal(t, id1, id2)
 }
+
+func TestListNamespace(t *testing.T) {
+	datastore, err := OpenForTest("ListNamespaces", true)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	defer datastore.Close()
+
+	namespaces, err := datastore.ListNamespaces()
+	assert.Nil(t, err)
+	if assert.Len(t, namespaces, 2) {
+		for _, namespace := range namespaces {
+			switch namespace.Name {
+			case "debian:7", "debian:8":
+				continue
+			default:
+				assert.Error(t, fmt.Errorf("ListNamespaces should not have returned '%s'", namespace.Name))
+			}
+		}
+	}
+}

database/pgsql/queries.go

@@ -43,6 +43,8 @@ func init() {
     UNION
     SELECT id FROM new_namespace`
 
+	queries["l_namespace"] = `SELECT id, name FROM Namespace`
+
 	// feature.go
 	queries["soi_feature"] = `
     WITH new_feature AS (