Move ks8deps to api for now.

api/k8sdeps/kunstruct/hasher.go

@@ -0,0 +1,123 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package kunstruct
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"sigs.k8s.io/kustomize/v3/api/hasher"
+	"sigs.k8s.io/kustomize/v3/api/ifc"
+)
+
+// kustHash computes a hash of an unstructured object.
+type kustHash struct{}
+
+// NewKustHash returns a kustHash object
+func NewKustHash() *kustHash {
+	return &kustHash{}
+}
+
+// Hash returns a hash of either a ConfigMap or a Secret
+func (h *kustHash) Hash(m ifc.Kunstructured) (string, error) {
+	u := unstructured.Unstructured{
+		Object: m.Map(),
+	}
+	kind := u.GetKind()
+	switch kind {
+	case "ConfigMap":
+		cm, err := unstructuredToConfigmap(u)
+		if err != nil {
+			return "", err
+		}
+		return configMapHash(cm)
+	case "Secret":
+		sec, err := unstructuredToSecret(u)
+
+		if err != nil {
+			return "", err
+		}
+		return secretHash(sec)
+	default:
+		return "", fmt.Errorf(
+			"type %s is not supported for hashing in %v",
+			kind, m.Map())
+	}
+}
+
+// configMapHash returns a hash of the ConfigMap.
+// The Data, Kind, and Name are taken into account.
+func configMapHash(cm *v1.ConfigMap) (string, error) {
+	encoded, err := encodeConfigMap(cm)
+	if err != nil {
+		return "", err
+	}
+	h, err := hasher.Encode(hasher.Hash(encoded))
+	if err != nil {
+		return "", err
+	}
+	return h, nil
+}
+
+// SecretHash returns a hash of the Secret.
+// The Data, Kind, Name, and Type are taken into account.
+func secretHash(sec *v1.Secret) (string, error) {
+	encoded, err := encodeSecret(sec)
+	if err != nil {
+		return "", err
+	}
+	h, err := hasher.Encode(hasher.Hash(encoded))
+	if err != nil {
+		return "", err
+	}
+	return h, nil
+}
+
+// encodeConfigMap encodes a ConfigMap.
+// Data, Kind, and Name are taken into account.
+func encodeConfigMap(cm *v1.ConfigMap) (string, error) {
+	// json.Marshal sorts the keys in a stable order in the encoding
+	m := map[string]interface{}{"kind": "ConfigMap", "name": cm.Name, "data": cm.Data}
+	if len(cm.BinaryData) > 0 {
+		m["binaryData"] = cm.BinaryData
+	}
+	data, err := json.Marshal(m)
+	if err != nil {
+		return "", err
+	}
+	return string(data), nil
+}
+
+// encodeSecret encodes a Secret.
+// Data, Kind, Name, and Type are taken into account.
+func encodeSecret(sec *v1.Secret) (string, error) {
+	// json.Marshal sorts the keys in a stable order in the encoding
+	data, err := json.Marshal(map[string]interface{}{"kind": "Secret", "type": sec.Type, "name": sec.Name, "data": sec.Data})
+	if err != nil {
+		return "", err
+	}
+	return string(data), nil
+}
+
+func unstructuredToConfigmap(u unstructured.Unstructured) (*v1.ConfigMap, error) {
+	marshaled, err := json.Marshal(u.Object)
+	if err != nil {
+		return nil, err
+	}
+	var out v1.ConfigMap
+	err = json.Unmarshal(marshaled, &out)
+	return &out, err
+}
+
+func unstructuredToSecret(u unstructured.Unstructured) (*v1.Secret, error) {
+	marshaled, err := json.Marshal(u.Object)
+	if err != nil {
+		return nil, err
+	}
+	var out v1.Secret
+	err = json.Unmarshal(marshaled, &out)
+	return &out, err
+}