// Copyright 2012 The Gorilla Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package sessions
import (
"encoding/gob"
"fmt"
"net/http"
"time"
"github.com/webx-top/echo"
)
// Default flashes key.
const flashesKey = "_flash"
// Options --------------------------------------------------------------------
// Options stores configuration for a session or session store.
//
// Fields are a subset of http.Cookie fields.
type Options struct {
Path string
Domain string
// MaxAge=0 means no 'Max-Age' attribute specified.
// MaxAge<0 means delete cookie now, equivalently 'Max-Age: 0'.
// MaxAge>0 means Max-Age attribute present and given in seconds.
MaxAge int
Secure bool
HttpOnly bool
}
// Session --------------------------------------------------------------------
// NewSession is called by session stores to create a new session instance.
func NewSession(store Store, name string) *Session {
return &Session{
Values: make(map[interface{}]interface{}),
store: store,
name: name,
}
}
// Session stores the values and optional configuration for a session.
type Session struct {
// The ID of the session, generated by stores. It should not be used for
// user data.
ID string
// Values contains the user-data for the session.
Values map[interface{}]interface{}
Options *Options
IsNew bool
store Store
name string
}
// Flashes returns a slice of flash messages from the session.
//
// A single variadic argument is accepted, and it is optional: it defines
// the flash key. If not defined "_flash" is used by default.
func (s *Session) Flashes(vars ...string) []interface{} {
var flashes []interface{}
key := flashesKey
if len(vars) > 0 {
key = vars[0]
}
if v, ok := s.Values[key]; ok {
// Drop the flashes and return it.
delete(s.Values, key)
flashes = v.([]interface{})
}
return flashes
}
// AddFlash adds a flash message to the session.
//
// A single variadic argument is accepted, and it is optional: it defines
// the flash key. If not defined "_flash" is used by default.
func (s *Session) AddFlash(value interface{}, vars ...string) {
key := flashesKey
if len(vars) > 0 {
key = vars[0]
}
var flashes []interface{}
if v, ok := s.Values[key]; ok {
flashes = v.([]interface{})
}
s.Values[key] = append(flashes, value)
}
// Save is a convenience method to save this session. It is the same as calling
// store.Save(request, response, session). You should call Save before writing to
// the response or returning from the handler.
func (s *Session) Save(ctx echo.Context) error {
return s.store.Save(ctx, s)
}
// Name returns the name used to register the session.
func (s *Session) Name() string {
return s.name
}
// Store returns the session store used to register the session.
func (s *Session) Store() Store {
return s.store
}
// Registry -------------------------------------------------------------------
// sessionInfo stores a session tracked by the registry.
type sessionInfo struct {
s *Session
e error
}
// registryKey is the key used to store the registry in the context.
const registryKey = `webx:mw.sessions`
// GetRegistry returns a registry instance for the current request.
func GetRegistry(ctx echo.Context) *Registry {
registry, ok := ctx.Get(registryKey).(*Registry)
if ok {
return registry
}
registry = &Registry{
context: ctx,
sessions: make(map[string]sessionInfo),
}
ctx.Set(registryKey, registry)
return registry
}
// Registry stores sessions used during a request.
type Registry struct {
context echo.Context
sessions map[string]sessionInfo
}
// Get registers and returns a session for the given name and session store.
//
// It returns a new session if there are no sessions registered for the name.
func (s *Registry) Get(store Store, name string) (session *Session, err error) {
if !isCookieNameValid(name) {
return nil, fmt.Errorf("sessions: invalid character in cookie name: %s", name)
}
if info, ok := s.sessions[name]; ok {
session, err = info.s, info.e
} else {
session, err = store.New(s.context, name)
session.name = name
s.sessions[name] = sessionInfo{s: session, e: err}
}
session.store = store
return
}
// Save saves all sessions registered for the current request.
func (s *Registry) Save(ctx echo.Context) error {
var errMulti MultiError
for name, info := range s.sessions {
session := info.s
if session.store == nil {
errMulti = append(errMulti, fmt.Errorf(
"sessions: missing store for session %q", name))
} else if err := session.store.Save(ctx, session); err != nil {
errMulti = append(errMulti, fmt.Errorf(
"sessions: error saving session %q -- %v", name, err))
}
}
if errMulti != nil {
return errMulti
}
return nil
}
// Helpers --------------------------------------------------------------------
func init() {
gob.Register([]interface{}{})
}
// Save saves all sessions used during the current request.
func Save(ctx echo.Context) error {
return GetRegistry(ctx).Save(ctx)
}
// NewCookie returns an http.Cookie with the options set. It also sets
// the Expires field calculated based on the MaxAge value, for Internet
// Explorer compatibility.
func NewCookie(name, value string, options *Options) *http.Cookie {
cookie := &http.Cookie{
Name: name,
Value: value,
Path: options.Path,
Domain: options.Domain,
MaxAge: options.MaxAge,
Secure: options.Secure,
HttpOnly: options.HttpOnly,
}
if options.MaxAge > 0 {
d := time.Duration(options.MaxAge) * time.Second
cookie.Expires = time.Now().Add(d)
} else if options.MaxAge < 0 {
// Set it to the past to expire now.
cookie.Expires = time.Unix(1, 0)
}
return cookie
}
// SetCookie for echo
func SetCookie(ctx echo.Context, key string, value string, options *Options) {
ctx.SetCookie(
key, value,
options.MaxAge,
options.Path,
options.Domain,
options.Secure,
options.HttpOnly,
)
}
// Error ----------------------------------------------------------------------
// MultiError stores multiple errors.
//
// Borrowed from the App Engine SDK.
type MultiError []error
func (m MultiError) Error() string {
s, n := "", 0
for _, e := range m {
if e != nil {
if n == 0 {
s = e.Error()
}
n++
}
}
switch n {
case 0:
return "(0 errors)"
case 1:
return s
case 2:
return s + " (and 1 other error)"
}
return fmt.Sprintf("%s (and %d other errors)", s, n-1)
}
