yaml namespaces

yaml.go

@@ -0,0 +1,129 @@
+package storage
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+const (
+	yamlExt = ".yaml"
+)
+
+type Yaml struct {
+	path string
+}
+
+func NewYaml(p string) (*Yaml, error) {
+	_, err := os.Stat(path.Dir(p))
+	if err != nil {
+		return nil, err
+	}
+	p, err = filepath.Abs(p)
+	if err != nil {
+		return nil, err
+	}
+	return &Yaml{
+		path: p,
+	}, os.MkdirAll(path.Dir(p), os.ModePerm)
+}
+
+func (y *Yaml) Namespaces() ([][]string, error) {
+	m, err := y.getMap()
+	if err != nil {
+		return nil, err
+	}
+	return keysDFS(m)
+}
+
+func (y *Yaml) List(ns []string, limits ...string) ([]string, error) {
+	return nil, errors.New("not impl")
+}
+
+func (y *Yaml) Get(key string, ns ...string) ([]byte, error) {
+	r, err := y.GetStream(key, ns...)
+	if err != nil {
+		return nil, err
+	}
+	return ioutil.ReadAll(r)
+}
+
+func (y *Yaml) GetStream(key string, ns ...string) (io.Reader, error) {
+	return nil, errors.New("not impl")
+}
+
+func (y *Yaml) Set(key string, value []byte, ns ...string) error {
+	r := bytes.NewReader(value)
+	if value == nil {
+		return y.Del(key, ns...)
+	}
+	return y.SetStream(key, r, ns...)
+}
+
+func (y *Yaml) Del(key string, ns ...string) error {
+	return errors.New("not impl")
+}
+
+func (y *Yaml) SetStream(key string, r io.Reader, ns ...string) error {
+	return errors.New("not impl")
+}
+
+func (y *Yaml) Close() error {
+	return nil
+}
+
+func (y *Yaml) getMap() (map[string]interface{}, error) {
+	b, err := y.get()
+	if err != nil {
+		return nil, err
+	}
+	var m map[string]interface{}
+	err = yaml.Unmarshal(b, &m)
+	return m, err
+}
+
+func (y *Yaml) get() ([]byte, error) {
+	b, err := ioutil.ReadFile(y.path)
+	if err == os.ErrNotExist {
+		return []byte{}, nil
+	}
+	return b, err
+}
+
+func (y *Yaml) set(b []byte) error {
+	return ioutil.WriteFile(y.path, b, os.ModePerm)
+}
+
+func keysDFS(m map[string]interface{}) ([][]string, error) {
+	keys, _, err := _keysDFS(m)
+	return keys, err
+}
+
+func _keysDFS(m map[string]interface{}) ([][]string, bool, error) {
+	keys := make([][]string, 0)
+	hasNonMaps := false
+	for k, v := range m {
+		if subm, ok := v.(map[string]interface{}); ok {
+			subkeys, hasElements, err := _keysDFS(subm)
+			if err != nil {
+				return nil, false, err
+			}
+			if hasElements {
+				subkeys = append(subkeys, []string{})
+			}
+			for i := range subkeys {
+				subkeys[i] = append([]string{k}, subkeys[i]...)
+				keys = append(keys, subkeys[i])
+			}
+		} else {
+			hasNonMaps = true
+		}
+	}
+	return keys, hasNonMaps, nil
+}