add conf paladin

go.mod

@@ -1,7 +1,9 @@
 module github.com/bilibili/Kratos
 
 require (
+	github.com/BurntSushi/toml v0.3.1
 	github.com/fatih/color v1.7.0
+	github.com/fsnotify/fsnotify v1.4.7
 	github.com/go-playground/locales v0.12.1 // indirect
 	github.com/go-playground/universal-translator v0.16.0 // indirect
 	github.com/gogo/protobuf v1.2.0

pkg/conf/paladin/README.md

@@ -0,0 +1,72 @@
+#### paladin
+
+##### 项目简介
+
+paladin 是一个config SDK客户端，包括了file、mock几个抽象功能，方便使用本地文件或者sven配置中心，并且集成了对象自动reload功能。  
+
+
+local files:
+```
+demo -conf=/data/conf/app/msm-servie.toml
+// or dir
+demo -conf=/data/conf/app/
+
+```
+example:
+```
+type exampleConf struct {
+	Bool   bool
+	Int    int64
+	Float  float64
+	String string
+}
+
+func (e *exampleConf) Set(text string) error {
+	var ec exampleConf
+	if err := toml.Unmarshal([]byte(text), &ec); err != nil {
+		return err
+	}
+	*e = ec
+	return nil
+}
+
+func ExampleClient() {
+	if err := paladin.Init(); err != nil {
+		panic(err)
+	}
+	var (
+		ec   exampleConf
+		eo   exampleConf
+		m    paladin.TOML
+		strs []string
+	)
+	// config unmarshal
+	if err := paladin.Get("example.toml").UnmarshalTOML(&ec); err != nil {
+		panic(err)
+	}
+	// config setter
+	if err := paladin.Watch("example.toml", &ec); err != nil {
+        panic(err)
+    }
+	// paladin map
+	if err := paladin.Watch("example.toml", &m); err != nil {
+        panic(err)
+    }
+	s, err := m.Value("key").String()
+	b, err := m.Value("key").Bool()
+	i, err := m.Value("key").Int64()
+	f, err := m.Value("key").Float64()
+	// value slice
+	err = m.Value("strings").Slice(&strs)
+	// watch key
+	for event := range paladin.WatchEvent(context.TODO(), "key") {
+		fmt.Println(event)
+	}
+}
+```
+
+##### 编译环境
+
+- **请只用 Golang v1.12.x 以上版本编译执行**
+
+##### 依赖包

pkg/conf/paladin/client.go

@@ -0,0 +1,49 @@
+package paladin
+
+import (
+	"context"
+)
+
+const (
+	// EventAdd config add event.
+	EventAdd EventType = iota
+	// EventUpdate config update event.
+	EventUpdate
+	// EventRemove config remove event.
+	EventRemove
+)
+
+// EventType is config event.
+type EventType int
+
+// Event is watch event.
+type Event struct {
+	Event EventType
+	Key   string
+	Value string
+}
+
+// Watcher is config watcher.
+type Watcher interface {
+	WatchEvent(context.Context, ...string) <-chan Event
+	Close() error
+}
+
+// Setter is value setter.
+type Setter interface {
+	Set(string) error
+}
+
+// Getter is value getter.
+type Getter interface {
+	// Get a config value by a config key(may be a sven filename).
+	Get(string) *Value
+	// GetAll return all config key->value map.
+	GetAll() *Map
+}
+
+// Client is config client.
+type Client interface {
+	Watcher
+	Getter
+}

pkg/conf/paladin/default.go

@@ -0,0 +1,86 @@
+package paladin
+
+import (
+	"context"
+	"flag"
+
+	"github.com/bilibili/Kratos/pkg/log"
+)
+
+var (
+	// DefaultClient default client.
+	DefaultClient Client
+	confPath      string
+	vars          = make(map[string][]Setter) // NOTE: no thread safe
+)
+
+func init() {
+	flag.StringVar(&confPath, "conf", "", "default config path")
+}
+
+// Init init config client.
+func Init() (err error) {
+	if confPath != "" {
+		DefaultClient, err = NewFile(confPath)
+	} else {
+		// TODO: config service
+		return
+	}
+	if err != nil {
+		return
+	}
+	go func() {
+		for event := range DefaultClient.WatchEvent(context.Background()) {
+			if event.Event != EventUpdate && event.Event != EventAdd {
+				continue
+			}
+			if sets, ok := vars[event.Key]; ok {
+				for _, s := range sets {
+					if err := s.Set(event.Value); err != nil {
+						log.Error("paladin: vars:%v event:%v error(%v)", s, event, err)
+					}
+				}
+			}
+		}
+	}()
+	return
+}
+
+// Watch watch on a key. The configuration implements the setter interface, which is invoked when the configuration changes.
+func Watch(key string, s Setter) error {
+	v := DefaultClient.Get(key)
+	str, err := v.Raw()
+	if err != nil {
+		return err
+	}
+	if err := s.Set(str); err != nil {
+		return err
+	}
+	vars[key] = append(vars[key], s)
+	return nil
+}
+
+// WatchEvent watch on multi keys. Events are returned when the configuration changes.
+func WatchEvent(ctx context.Context, keys ...string) <-chan Event {
+	return DefaultClient.WatchEvent(ctx, keys...)
+}
+
+// Get return value by key.
+func Get(key string) *Value {
+	return DefaultClient.Get(key)
+}
+
+// GetAll return all config map.
+func GetAll() *Map {
+	return DefaultClient.GetAll()
+}
+
+// Keys return values key.
+func Keys() []string {
+	return DefaultClient.GetAll().Keys()
+}
+
+// Close close watcher.
+func Close() error {
+	return DefaultClient.Close()
+}

pkg/conf/paladin/example_test.go

@@ -0,0 +1,112 @@
+package paladin_test
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/bilibili/Kratos/pkg/conf/paladin"
+
+	"github.com/BurntSushi/toml"
+)
+
+type exampleConf struct {
+	Bool    bool
+	Int     int64
+	Float   float64
+	String  string
+	Strings []string
+}
+
+func (e *exampleConf) Set(text string) error {
+	var ec exampleConf
+	if err := toml.Unmarshal([]byte(text), &ec); err != nil {
+		return err
+	}
+	*e = ec
+	return nil
+}
+
+// ExampleClient is a example client usage.
+// exmaple.toml:
+/*
+	bool = true
+	int = 100
+	float = 100.1
+	string = "text"
+	strings = ["a", "b", "c"]
+*/
+func ExampleClient() {
+	if err := paladin.Init(); err != nil {
+		panic(err)
+	}
+	var ec exampleConf
+	// var setter
+	if err := paladin.Watch("example.toml", &ec); err != nil {
+		panic(err)
+	}
+	if err := paladin.Get("example.toml").UnmarshalTOML(&ec); err != nil {
+		panic(err)
+	}
+	// use exampleConf
+	// watch event key
+	go func() {
+		for event := range paladin.WatchEvent(context.TODO(), "key") {
+			fmt.Println(event)
+		}
+	}()
+}
+
+// ExampleMap is a example map usage.
+// exmaple.toml:
+/*
+	bool = true
+	int = 100
+	float = 100.1
+	string = "text"
+	strings = ["a", "b", "c"]
+
+	[object]
+	string = "text"
+	bool = true
+	int = 100
+	float = 100.1
+	strings = ["a", "b", "c"]
+*/
+func ExampleMap() {
+	var (
+		m    paladin.TOML
+		strs []string
+	)
+	// paladin toml
+	if err := paladin.Watch("example.toml", &m); err != nil {
+		panic(err)
+	}
+	// value string
+	s, err := m.Get("string").String()
+	if err != nil {
+		s = "default"
+	}
+	fmt.Println(s)
+	// value bool
+	b, err := m.Get("bool").Bool()
+	if err != nil {
+		b = false
+	}
+	fmt.Println(b)
+	// value int
+	i, err := m.Get("int").Int64()
+	if err != nil {
+		i = 100
+	}
+	fmt.Println(i)
+	// value float
+	f, err := m.Get("float").Float64()
+	if err != nil {
+		f = 100.1
+	}
+	fmt.Println(f)
+	// value slice
+	if err = m.Get("strings").Slice(&strs); err == nil {
+		fmt.Println(strs)
+	}
+}