session

1. session move from astaxie/session to beego/session
2. support 4 type session

session/session.go

@@ -0,0 +1,97 @@
+package session
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+type SessionStore interface {
+	Set(key, value interface{}) error //set session value
+	Get(key interface{}) interface{}  //get session value
+	Delete(key interface{}) error     //delete session value
+	SessionID() string                //back current sessionID
+	SessionRelease()                  // release the resource
+}
+
+type Provider interface {
+	SessionInit(maxlifetime int64, savePath string) error
+	SessionRead(sid string) (SessionStore, error)
+	SessionDestroy(sid string) error
+	SessionGC()
+}
+
+var provides = make(map[string]Provider)
+
+// Register makes a session provide available by the provided name.
+// If Register is called twice with the same name or if driver is nil,
+// it panics.
+func Register(name string, provide Provider) {
+	if provide == nil {
+		panic("session: Register provide is nil")
+	}
+	if _, dup := provides[name]; dup {
+		panic("session: Register called twice for provider " + name)
+	}
+	provides[name] = provide
+}
+
+type Manager struct {
+	cookieName  string //private cookiename
+	provider    Provider
+	maxlifetime int64
+}
+
+func NewManager(provideName, cookieName string, maxlifetime int64, savePath string) (*Manager, error) {
+	provider, ok := provides[provideName]
+	if !ok {
+		return nil, fmt.Errorf("session: unknown provide %q (forgotten import?)", provideName)
+	}
+	provider.SessionInit(maxlifetime, savePath)
+	return &Manager{provider: provider, cookieName: cookieName, maxlifetime: maxlifetime}, nil
+}
+
+//get Session
+func (manager *Manager) SessionStart(w http.ResponseWriter, r *http.Request) (session SessionStore) {
+	cookie, err := r.Cookie(manager.cookieName)
+	if err != nil || cookie.Value == "" {
+		sid := manager.sessionId()
+		session, _ = manager.provider.SessionRead(sid)
+		cookie := http.Cookie{Name: manager.cookieName, Value: url.QueryEscape(sid), Path: "/", HttpOnly: true, MaxAge: int(manager.maxlifetime)}
+		http.SetCookie(w, &cookie)
+	} else {
+		sid, _ := url.QueryUnescape(cookie.Value)
+		session, _ = manager.provider.SessionRead(sid)
+	}
+	return
+}
+
+//Destroy sessionid
+func (manager *Manager) SessionDestroy(w http.ResponseWriter, r *http.Request) {
+	cookie, err := r.Cookie(manager.cookieName)
+	if err != nil || cookie.Value == "" {
+		return
+	} else {
+		manager.provider.SessionDestroy(cookie.Value)
+		expiration := time.Now()
+		cookie := http.Cookie{Name: manager.cookieName, Path: "/", HttpOnly: true, Expires: expiration, MaxAge: -1}
+		http.SetCookie(w, &cookie)
+	}
+}
+
+func (manager *Manager) GC() {
+	manager.provider.SessionGC()
+	time.AfterFunc(time.Duration(manager.maxlifetime)*time.Second, func() { manager.GC() })
+}
+
+func (manager *Manager) sessionId() string {
+	b := make([]byte, 24)
+	if _, err := io.ReadFull(rand.Reader, b); err != nil {
+		return ""
+	}
+	return base64.URLEncoding.EncodeToString(b)
+}