Allow to set alternative cookie name

session.go

@@ -47,12 +47,15 @@ import (
  "time"
 )
 
-const cookieName = "session"
+const defaultCookieName = "session"
 
-var ErrCookieTooLong = errors.New("session: cookie length greater than 4096 bytes")
+var ErrCookieTooLong = errors.New("cookie length greater than 4096 bytes")
 
 // Session holds the configuration settings that you want to use for your sessions.
 type Session struct {
+ // Name of the cookie key
+ CookieName string
+
  // Domain sets the 'Domain' attribute on the session cookie. By default
  // it will be set to the domain name that the cookie was issued from.
  Domain string
@@ -98,26 +101,40 @@ type Session struct {
  keys [][32]byte
 }
 
+type Params struct {
+ // Required.
+ // The Key parameter is the secret you want to use to authenticate and encrypt
+ // session cookies. It should be exactly 32 bytes long.
+ Key []byte
+ // Optional. The OldKeys parameter can be used to provide an arbitrary
+ // number of old Keys. This can be used to ensure that valid cookies continue
+ // to work correctly after key rotation.
+ OldKeys [][]byte
+ // Optional. Default is `session`.
+ // An alternative cookie name can be used for resolving collisions with
+ // the other packages which use the cookie of the same name, or for overcoming
+ // the 4096 bytes value limit by creating several cookie storages.
+ CookieName string
+}
+
 // New initializes a new Session object to hold the configuration settings for
 // your sessions.
-//
-// The key parameter is the secret you want to use to authenticate and encrypt
-// session cookies. It should be exactly 32 bytes long.
-//
-// Optionally, the variadic oldKeys parameter can be used to provide an arbitrary
-// number of old Keys. This can be used to ensure that valid cookies continue
-// to work correctly after key rotation.
-func New(key []byte, oldKeys ...[]byte) *Session {
+func NewWithParams(params Params) *Session {
+ if len(params.Key) == 0 {
+ panic(`parameter Key must be provided`)
+ }
+
  keys := make([][32]byte, 1)
- copy(keys[0][:], key)
+ copy(keys[0][:], params.Key)
 
- for _, key := range oldKeys {
+ for _, key := range params.OldKeys {
  var newKey [32]byte
  copy(newKey[:], key)
  keys = append(keys, newKey)
  }
 
  return &Session{
+ CookieName: params.CookieName,
  Domain: "",
  HttpOnly: true,
  Lifetime: 24 * time.Hour,
@@ -130,6 +147,18 @@ func New(key []byte, oldKeys ...[]byte) *Session {
  }
 }
 
+// Simplified Session initilizer.
+// The same as NewWithParams(), with default 'session' cookie name.
+func New(key []byte, oldKeys ...[]byte) *Session {
+ params := Params{
+ Key: key,
+ OldKeys: oldKeys,
+ CookieName: defaultCookieName,
+ }
+
+ return NewWithParams(params)
+}
+
 // Enable is middleware which loads and saves session data to and from the
 // session cookie. You should use this middleware to wrap ALL handlers which
 // need to access to the session data. A common way to do this is to wrap your
@@ -168,7 +197,7 @@ func (s *Session) Enable(next http.Handler) http.Handler {
 }
 
 func (s *Session) load(r *http.Request) (*cache, error) {
- cookie, err := r.Cookie(cookieName)
+ cookie, err := r.Cookie(s.CookieName)
  if err == http.ErrNoCookie {
  return newCache(s.Lifetime), nil
  } else if err != nil {
@@ -200,7 +229,7 @@ func (s *Session) save(w http.ResponseWriter, c *cache) error {
 
  if c.destroyed {
  http.SetCookie(w, &http.Cookie{
- Name: cookieName,
+ Name: s.CookieName,
  Value: "",
  Path: s.Path,
  Domain: s.Domain,
@@ -219,7 +248,7 @@ func (s *Session) save(w http.ResponseWriter, c *cache) error {
  }
 
  cookie := &http.Cookie{
- Name: cookieName,
+ Name: s.CookieName,
  Value: token,
  Path: s.Path,
  Domain: s.Domain,

session_test.go

@@ -70,8 +70,8 @@ func TestDestroy(t *testing.T) {
 
  _, cookie := testRequest(t, s.Enable(h), "")
 
- if !strings.HasPrefix(cookie, fmt.Sprintf("%s=;", cookieName)) {
- t.Errorf("got %q: expected prefix %q", cookie, fmt.Sprintf("%s=;", cookieName))
+ if !strings.HasPrefix(cookie, fmt.Sprintf("%s=;", s.CookieName)) {
+ t.Errorf("got %q: expected prefix %q", cookie, fmt.Sprintf("%s=;", s.CookieName))
  }
  if !strings.Contains(cookie, "Expires=Thu, 01 Jan 1970 00:00:01 GMT") {
  t.Errorf("got %q: expected to contain %q", cookie, "Expires=Thu, 01 Jan 1970 00:00:01 GMT")
@@ -121,7 +121,7 @@ func TestInvalidCookies(t *testing.T) {
  s := New([]byte("u46IpCV9y5Vlur8YvODJEhgOY8m9JVE4"))
 
  cookie := &http.Cookie{
- Name: cookieName,
+ Name: s.CookieName,
  Value: "",
  }
 
@@ -135,7 +135,7 @@ func TestInvalidCookies(t *testing.T) {
  }
 
  cookie = &http.Cookie{
- Name: cookieName,
+ Name: s.CookieName,
  Value: "`",
  }