session: add ability to start in Created State

TODO: test

Author: ellemouton

session/interface.go

@@ -27,9 +27,10 @@ const (
 type State uint8
 
 /*
-				   /---> StateExpired
-StateReserved ---> StateCreated ---
-       				   \---> StateRevoked
+
+--> ------------------\		       /---> StateExpired
+--> StateReserved ---> StateCreated ---
+       				       \---> StateRevoked
 */
 
 const (
@@ -102,7 +103,12 @@ func buildSession(id ID, localPrivKey *btcec.PrivateKey, label string, typ Type,
 	created, expiry time.Time, serverAddr string, devServer bool,
 	perms []bakery.Op, caveats []macaroon.Caveat,
 	featureConfig FeaturesConfig, privacy bool, linkedGroupID *ID,
-	flags PrivacyFlags) (*Session, error) {
+	flags PrivacyFlags, options ...Option) (*Session, error) {
+
+	opts := defaultSessionOptions()
+	for _, o := range options {
+		o(opts)
+	}
 
 	_, pairingSecret, err := mailbox.NewPassphraseEntropy()
 	if err != nil {
@@ -139,6 +145,10 @@ func buildSession(id ID, localPrivKey *btcec.PrivateKey, label string, typ Type,
 		GroupID:           groupID,
 	}
 
+	if opts.immediateActivation {
+		sess.State = StateCreated
+	}
+
 	if perms != nil || caveats != nil {
 		sess.MacaroonRecipe = &MacaroonRecipe{
 			Permissions: perms,
@@ -163,6 +173,34 @@ type IDToGroupIndex interface {
 	GetSessionIDs(groupID ID) ([]ID, error)
 }
 
+// sessionOptions defines various options that can be tweaked via functional
+// parameters for session creation.
+type sessionOptions struct {
+	// immediateActivation can be used to immediately move a session to
+	// the StateCreated state on creation.
+	immediateActivation bool
+}
+
+// defaultSessionOptions returns a new sessionOptions struct with default
+// values set.
+func defaultSessionOptions() *sessionOptions {
+	return &sessionOptions{
+		immediateActivation: false,
+	}
+}
+
+// Option defines the signature of a functional option that can be used to
+// tweak various session creation options.
+type Option func(*sessionOptions)
+
+// WithImmediateActivation can be used to immediately move a session to the
+// StateCreated state on creation.
+func WithImmediateActivation() Option {
+	return func(o *sessionOptions) {
+		o.immediateActivation = true
+	}
+}
+
 // Store is the interface a persistent storage must implement for storing and
 // retrieving Terminal Connect sessions.
 type Store interface {
@@ -172,7 +210,7 @@ type Store interface {
 	NewSession(label string, typ Type, expiry time.Time, serverAddr string,
 		devServer bool, perms []bakery.Op, caveats []macaroon.Caveat,
 		featureConfig FeaturesConfig, privacy bool, linkedGroupID *ID,
-		flags PrivacyFlags) (*Session, error)
+		flags PrivacyFlags, opts ...Option) (*Session, error)
 
 	// CreateSession moves the given session from the StateReserved state to
 	// the StateCreated state.

session/kvdb_store.go

@@ -190,7 +190,8 @@ func getSessionKey(session *Session) []byte {
 func (db *BoltStore) NewSession(label string, typ Type, expiry time.Time,
 	serverAddr string, devServer bool, perms []bakery.Op,
 	caveats []macaroon.Caveat, featureConfig FeaturesConfig, privacy bool,
-	linkedGroupID *ID, flags PrivacyFlags) (*Session, error) {
+	linkedGroupID *ID, flags PrivacyFlags, options ...Option) (*Session,
+	error) {
 
 	var session *Session
 	err := db.Update(func(tx *bbolt.Tx) error {
@@ -207,7 +208,7 @@ func (db *BoltStore) NewSession(label string, typ Type, expiry time.Time,
 		session, err = buildSession(
 			id, localPrivKey, label, typ, db.clock.Now(), expiry,
 			serverAddr, devServer, perms, caveats, featureConfig,
-			privacy, linkedGroupID, flags,
+			privacy, linkedGroupID, flags, options...,
 		)
 		if err != nil {
 			return err