init

Author: lunny

README.md

@@ -0,0 +1,39 @@
+flash [![Build Status](https://drone.io/github.com/tango-contrib/flash/status.png)](https://drone.io/github.com/tango-contrib/flash/latest) [![](http://gocover.io/_badge/github.com/tango-contrib/flash)](http://gocover.io/github.com/tango-contrib/flash)
+======
+
+Middleware flash is a tool for share data between requests for [Tango](https://github.com/lunny/tango). 
+
+## Notice
+
+This is a new version, it stores all data via [session](https://github.com/tango-contrib/session) not cookie. And it is slightly non-compitable with old version.
+
+## Installation
+
+    go get github.com/tango-contrib/flash
+
+## Simple Example
+
+```Go
+
+import "github.com/tango-contrib/session"
+
+type FlashAction struct {
+    flash.Flash
+}
+
+func (x *FlashAction) Get() {
+    x.Flash.Set("test", "test")
+}
+
+func (x *FlashAction) Post() {
+   x.Flash.Get("test").(string) == "test"
+}
+
+func main() {
+    t := tango.Classic()
+    sessions := session.Sessions()
+    t.Use(flash.Flashes(sessions))
+    t.Any("/", new(FlashAction))
+    t.Run()
+}
+```

flash.go

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+package flash
+
+import (
+	"github.com/lunny/tango"
+	"github.com/tango-contrib/session"
+)
+
+var (
+	FlashName      = "tango_flash"
+	FlashSeperator = "TANGOFLASH"
+
+	_ Flasher = &Flash{}
+)
+
+type Data map[string]interface{}
+
+// FlashData is a tools to maintain data when using across request.
+type Flash struct {
+	readed  Data
+	flushed Data
+	session *session.Session
+	*Options
+	saved bool
+}
+
+func (f *Flash) setFlash(sess *session.Session, readed Data, opt *Options) {
+	f.readed = readed
+	f.flushed = make(Data)
+	f.session = sess
+	f.Options = opt
+}
+
+func (f *Flash) FlushData() Data {
+	return f.flushed
+}
+
+func (f *Flash) Merge() {
+	for k, v := range f.readed {
+		f.flushed[k] = v
+	}
+}
+
+func (f *Flash) Data() Data {
+	return f.readed
+}
+
+func (f *Flash) Get(key string) interface{} {
+	return f.readed[key]
+}
+
+func (f *Flash) Set(key string, value interface{}) {
+	f.readed[key] = value
+	f.flushed[key] = value
+}
+
+func (f *Flash) Add(kvs Data) {
+	for k, v := range kvs {
+		f.Set(k, v)
+	}
+}
+
+func (f *Flash) Save() {
+	if f.saved {
+		return
+	}
+
+	for key, _ := range f.readed {
+		f.session.Del(f.Options.FlashName+f.Options.FlashSeperator+key)
+	}
+
+	var keys = make([]string, 0)
+	for k, v := range f.flushed {
+		f.session.Set(f.Options.FlashName+f.Options.FlashSeperator+k, v)
+		keys = append(keys, k)
+	}
+	f.session.Set(f.Options.FlashName, keys)
+	f.saved = true
+}
+
+type Flasher interface {
+	setFlash(*session.Session, Data, *Options)
+	FlushData() Data
+	Save()
+}
+
+type Options struct {
+	FlashName      string
+	FlashSeperator string
+}
+
+func prepareOptions(opts []Options) Options {
+	var opt Options
+	if len(opts) > 0 {
+		opt = opts[0]
+	}
+
+	if len(opt.FlashName) == 0 {
+		opt.FlashName = FlashName
+	}
+	if len(opt.FlashSeperator) == 0 {
+		opt.FlashSeperator = FlashSeperator
+	}
+	return opt
+}
+
+// Flash return a FlashData handler.
+func Flashes(sessions *session.Sessions, opts ...Options) tango.HandlerFunc {
+	opt := prepareOptions(opts)
+	return func(ctx *tango.Context) {
+		var flasher Flasher
+		var ok bool
+		if action := ctx.Action(); action != nil {
+			if flasher, ok = action.(Flasher); ok {
+				sess := sessions.Session(ctx.Req(), ctx.ResponseWriter)
+				fd := make(Data)
+				if keys, has := sess.Get(opt.FlashName).([]string); has {
+					for _, key := range keys {
+						fd[key] = sess.Get(opt.FlashName+opt.FlashSeperator+key)
+					}
+				}
+				flasher.setFlash(sess, fd, &opt)
+			}
+		}
+
+		ctx.Next()
+
+		if ok {
+			flasher.Save()
+		}
+	}
+}