Add new constructor to create documents

The change would allow to build a document object from bytes

Change-Id: I15c13a960b4e989cffa4525c85b8f32f2a51a0e1
Relates-To: #238
Relates-To: #279
Closes: #279

pkg/document/constants.go

@@ -31,6 +31,9 @@ const (
 	SecretKind        = "Secret"
 	BareMetalHostKind = "BareMetalHost"
 
+	ConfigMapKind    = "ConfigMap"
+	ConfigMapVersion = "v1"
+
 	ClusterctlMetadataKind    = "Metadata"
 	ClusterctlMetadataVersion = "v1alpha3"
 	ClusterctlMetadataGroup   = "clusterctl.cluster.x-k8s.io"

pkg/document/document.go

@@ -15,6 +15,7 @@
 package document
 
 import (
+	"sigs.k8s.io/kustomize/api/k8sdeps/kunstruct"
 	"sigs.k8s.io/kustomize/api/resource"
 	"sigs.k8s.io/yaml"
 )
@@ -198,3 +199,14 @@ func NewDocument(r *resource.Resource) (Document, error) {
 	err := doc.SetKustomizeResource(r)
 	return doc, err
 }
+
+// NewDocumentFromBytes constructs document from bytes
+func NewDocumentFromBytes(b []byte) (Document, error) {
+	res, err := resource.NewFactory(kunstruct.NewKunstructuredFactoryImpl()).FromBytes(b)
+	if err != nil {
+		return nil, err
+	}
+	doc := &Factory{}
+	err = doc.SetKustomizeResource(res)
+	return doc, err
+}

pkg/document/document_test.go

@@ -158,3 +158,46 @@ func TestDocument(t *testing.T) {
 		}
 	})
 }
+
+func TestNewDocumentFromBytes(t *testing.T) {
+	tests := []struct {
+		name            string
+		stringData      string
+		expectErr       bool
+		expectedDocName string
+	}{
+		{
+			name: "ConfigMap",
+			stringData: `apiVersion: v1
+kind: Secret
+metadata:
+  name: control-0-bmc
+  namespace: metal3
+type: Opaque
+stringData:
+  username: username
+  password: password`,
+			expectErr:       false,
+			expectedDocName: "control-0-bmc",
+		},
+		{
+			name: "Manformed Bytes",
+			stringData: `
+			broken:fas -<
+				fasd`,
+			expectErr: true,
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			doc, err := document.NewDocumentFromBytes([]byte(tt.stringData))
+			if tt.expectErr {
+				assert.Error(t, err)
+			} else {
+				require.NoError(t, err)
+				assert.Equal(t, doc.GetName(), tt.expectedDocName)
+			}
+		})
+	}
+}