Refactoring backends, fixes #6

backend/backend.go

@@ -2,37 +2,47 @@
 package backend
 
 // A backend takes care of storing all mailbox data.
-type Backend interface {
+type Backend struct {
 	ContactsBackend
 	LabelsBackend
 	ConversationsBackend
 	SendBackend
 	DomainsBackend
 	EventsBackend
+	UsersBackend
+	KeysBackend
+}
 
-	// TODO: move all these methods to sub-backends
-
-	// Check if a username is available.
-	IsUsernameAvailable(username string) (bool, error)
-	// Get a user.
-	GetUser(id string) (*User, error)
-	// Check if the provided username and password are correct
-	Auth(username, password string) (*User, error)
-	// Insert a new user. Returns the newly created user.
-	InsertUser(user *User, password string) (*User, error)
-	// Update an existing user.
-	UpdateUser(update *UserUpdate) error
-	// Update a user's password.
-	UpdateUserPassword(id, current, new string) error
-	// Update a user's private key.
-	UpdateKeypair(id, password string, keypair *Keypair) error
-	// Delete a user.
-	//DeleteUser(id string) error
-
-	// Get a public key for a user.
-	GetPublicKey(email string) (string, error)
+// Set one or some of this backend's components.
+func (b *Backend) Set(backends ...interface{}) {
+	for _, bkd := range backends {
+		if contacts, ok := bkd.(ContactsBackend); ok {
+			b.ContactsBackend = contacts
+		}
+		if labels, ok := bkd.(LabelsBackend); ok {
+			b.LabelsBackend = labels
+		}
+		if conversations, ok := bkd.(ConversationsBackend); ok {
+			b.ConversationsBackend = conversations
+		}
+		if send, ok := bkd.(SendBackend); ok {
+			b.SendBackend = send
+		}
+		if domains, ok := bkd.(DomainsBackend); ok {
+			b.DomainsBackend = domains
+		}
+		if events, ok := bkd.(EventsBackend); ok {
+			b.EventsBackend = events
+		}
+		if users, ok := bkd.(UsersBackend); ok {
+			b.UsersBackend = users
+		}
+		if keys, ok := bkd.(KeysBackend); ok {
+			b.KeysBackend = keys
+		}
+	}
+}
 
-	// Set a backend.
-	// TODO: remove this
-	Set(item interface{}) error
+func New() *Backend {
+	return &Backend{}
 }

backend/imap/backend.go

@@ -1,55 +1,24 @@
 package imap
 
 import (
-	"errors"
-
 	"github.com/emersion/neutron/backend"
-	"github.com/emersion/neutron/backend/memory"
 	"github.com/emersion/neutron/backend/util"
 )
 
-type Backend struct {
-	backend.DomainsBackend
-	backend.ContactsBackend
-	backend.LabelsBackend
-	backend.ConversationsBackend
-	backend.SendBackend
-	backend.EventsBackend
-
-	*connBackend
-
-	users map[string]*backend.User
-	passwords map[string]string
+type Config struct {
+	Hostname string
+	Port int
+	Suffix string
 }
 
-func (b *Backend) Set(item interface{}) error {
-	switch val := item.(type) {
-	case backend.SendBackend:
-		b.SendBackend = val
-	default:
-		return errors.New("Unsupported backend")
-	}
-	return nil
-}
-
-func New(config *Config) backend.Backend {
-	bkd := &Backend{
-		connBackend: newConnBackend(config),
-
-		users: map[string]*backend.User{},
-		passwords: map[string]string{},
-	}
-
-	messages := newMessagesBackend(bkd.connBackend)
-	conversations := util.NewDummyConversationsBackend(messages)
+func Use(config *Config, bkd *backend.Backend) *Users {
+	conns := newConns(config)
+	messages := newMessages(conns)
+	conversations := util.NewDummyConversations(messages)
+	users := newUsers(conns)
 
-	// TODO: do not use memory backends
-	bkd.EventsBackend = memory.NewEventsBackend()
-	bkd.DomainsBackend = memory.NewDomainsBackend()
-	bkd.ContactsBackend = util.NewEventedContactsBackend(memory.NewContactsBackend(), bkd.EventsBackend)
-	bkd.LabelsBackend = util.NewEventedLabelsBackend(memory.NewLabelsBackend(), bkd.EventsBackend)
-	bkd.ConversationsBackend = util.NewEventedConversationsBackend(conversations, bkd.EventsBackend)
-	bkd.SendBackend = util.NewNoopSendBackend()
+	bkd.Set(conversations, users)
 
-	return bkd
+	// TODO: do not return users backend
+	return users
 }

backend/imap/conn.go

@@ -8,12 +8,6 @@ import (
 	"github.com/mxk/go-imap/imap"
 )
 
-type Config struct {
-	Hostname string
-	Port int
-	Suffix string
-}
-
 func (c *Config) Host() string {
 	host := c.Hostname
 	if c.Port > 0 {
@@ -22,34 +16,34 @@ func (c *Config) Host() string {
 	return host
 }
 
-type connBackend struct {
+type conns struct {
 	config *Config
-	conns map[string]*imap.Client
+	clients map[string]*imap.Client
 	locks map[string]sync.Locker
 }
 
-func (b *connBackend) insertConn(user string, conn *imap.Client) {
-	b.conns[user] = conn
+func (b *conns) insertConn(user string, conn *imap.Client) {
+	b.clients[user] = conn
 	b.locks[user] = &sync.Mutex{}
 }
 
-func (b *connBackend) getConn(user string) (*imap.Client, func(), error) {
+func (b *conns) getConn(user string) (*imap.Client, func(), error) {
 	lock, ok := b.locks[user]
 	if !ok {
 		return nil, nil, errors.New("No such user")
 	}
 
 	lock.Lock()
 
-	conn, ok := b.conns[user]
+	conn, ok := b.clients[user]
 	if !ok {
 		lock.Unlock()
 		return nil, nil, errors.New("No such user")
 	}
 
 	state := conn.State()
 	if state == imap.Logout || state == imap.Closed {
-		delete(b.conns, user)
+		delete(b.clients, user)
 		delete(b.locks, user)
 		lock.Unlock()
 		return nil, nil, errors.New("Connection to IMAP server closed")
@@ -58,11 +52,11 @@ func (b *connBackend) getConn(user string) (*imap.Client, func(), error) {
 	return conn, lock.Unlock, nil
 }
 
-func newConnBackend(config *Config) *connBackend {
-	return &connBackend{
+func newConns(config *Config) *conns {
+	return &conns{
 		config: config,
 
-		conns: map[string]*imap.Client{},
+		clients: map[string]*imap.Client{},
 		locks: map[string]sync.Locker{},
 	}
 }

backend/imap/messages.go

@@ -14,8 +14,8 @@ import (
 	"github.com/emersion/neutron/backend/util/textproto"
 )
 
-type MessagesBackend struct {
-	*connBackend
+type Messages struct {
+	*conns
 
 	mailboxes map[string][]*imap.MailboxInfo
 }
@@ -119,7 +119,7 @@ func parseEnvelope(msg *backend.Message, envelope []imap.Field) {
 	// envelope[8] is Message-Id
 }
 
-func (b *MessagesBackend) getMailboxes(user string) ([]*imap.MailboxInfo, error) {
+func (b *Messages) getMailboxes(user string) ([]*imap.MailboxInfo, error) {
 	// Mailboxes list already retrieved
 	if len(b.mailboxes[user]) > 0 {
 		return b.mailboxes[user], nil
@@ -157,7 +157,7 @@ func (b *MessagesBackend) getMailboxes(user string) ([]*imap.MailboxInfo, error)
 	return b.mailboxes[user], nil
 }
 
-func (b *MessagesBackend) getLabelMailbox(user, label string) (mailbox string, err error) {
+func (b *Messages) getLabelMailbox(user, label string) (mailbox string, err error) {
 	mailboxes, err := b.getMailboxes(user)
 	if err != nil {
 		return
@@ -174,7 +174,7 @@ func (b *MessagesBackend) getLabelMailbox(user, label string) (mailbox string, e
 	return
 }
 
-func (b *MessagesBackend) selectMailbox(user, mailbox string) (err error) {
+func (b *Messages) selectMailbox(user, mailbox string) (err error) {
 	c, unlock, err := b.getConn(user)
 	if err != nil {
 		return
@@ -191,7 +191,7 @@ func (b *MessagesBackend) selectMailbox(user, mailbox string) (err error) {
 	return
 }
 
-func (b *MessagesBackend) selectLabelMailbox(user, label string) (err error) {
+func (b *Messages) selectLabelMailbox(user, label string) (err error) {
 	mailbox, err := b.getLabelMailbox(user, label)
 	if err != nil {
 		return
@@ -200,7 +200,7 @@ func (b *MessagesBackend) selectLabelMailbox(user, label string) (err error) {
 	return b.selectMailbox(user, mailbox)
 }
 
-func (b *MessagesBackend) GetMessage(user, id string) (msg *backend.Message, err error) {
+func (b *Messages) GetMessage(user, id string) (msg *backend.Message, err error) {
 	mailbox, uid, err := parseMessageId(id)
 	if err != nil {
 		return
@@ -257,7 +257,7 @@ func reverseMessagesList(msgs []*backend.Message) {
 	}
 }
 
-func (b *MessagesBackend) ListMessages(user string, filter *backend.MessagesFilter) (msgs []*backend.Message, total int, err error) {
+func (b *Messages) ListMessages(user string, filter *backend.MessagesFilter) (msgs []*backend.Message, total int, err error) {
 	if filter.Label == "" {
 		err = errors.New("Cannot list messages without specifying a label")
 		return
@@ -326,7 +326,7 @@ func (b *MessagesBackend) ListMessages(user string, filter *backend.MessagesFilt
 	return
 }
 
-func (b *MessagesBackend) CountMessages(user string) (counts []*backend.MessagesCount, err error) {
+func (b *Messages) CountMessages(user string) (counts []*backend.MessagesCount, err error) {
 	mailboxes, err := b.getMailboxes(user)
 	if err != nil {
 		return
@@ -356,7 +356,7 @@ func (b *MessagesBackend) CountMessages(user string) (counts []*backend.Messages
 	return
 }
 
-func (b *MessagesBackend) InsertMessage(user string, msg *backend.Message) (inserted *backend.Message, err error) {
+func (b *Messages) InsertMessage(user string, msg *backend.Message) (inserted *backend.Message, err error) {
 	mailbox, err := b.getLabelMailbox(user, backend.DraftLabel)
 	if err != nil {
 		return
@@ -387,7 +387,7 @@ func (b *MessagesBackend) InsertMessage(user string, msg *backend.Message) (inse
 	return
 }
 
-func (b *MessagesBackend) updateMessageFlags(user string, seqset *imap.SeqSet, flag string, value bool) error {
+func (b *Messages) updateMessageFlags(user string, seqset *imap.SeqSet, flag string, value bool) error {
 	item := "+FLAGS"
 	if !value {
 		item = "-FLAGS"
@@ -409,7 +409,7 @@ func (b *MessagesBackend) updateMessageFlags(user string, seqset *imap.SeqSet, f
 	return nil
 }
 
-func (b *MessagesBackend) deleteMessages(user string, seqset *imap.SeqSet) (err error) {
+func (b *Messages) deleteMessages(user string, seqset *imap.SeqSet) (err error) {
 	c, unlock, err := b.getConn(user)
 	if err != nil {
 		return
@@ -431,7 +431,7 @@ func (b *MessagesBackend) deleteMessages(user string, seqset *imap.SeqSet) (err
 }
 
 // TODO: only supports moving one single message
-func (b *MessagesBackend) copyMessages(user string, seqset *imap.SeqSet, mbox string) (uid uint32, err error) {
+func (b *Messages) copyMessages(user string, seqset *imap.SeqSet, mbox string) (uid uint32, err error) {
 	c, unlock, err := b.getConn(user)
 	if err != nil {
 		return
@@ -452,7 +452,7 @@ func (b *MessagesBackend) copyMessages(user string, seqset *imap.SeqSet, mbox st
 	return
 }
 
-func (b *MessagesBackend) moveMessages(user string, seqset *imap.SeqSet, mbox string) (uid uint32, err error) {
+func (b *Messages) moveMessages(user string, seqset *imap.SeqSet, mbox string) (uid uint32, err error) {
 	uid, err = b.copyMessages(user, seqset, mbox)
 	if err != nil {
 		return
@@ -462,7 +462,7 @@ func (b *MessagesBackend) moveMessages(user string, seqset *imap.SeqSet, mbox st
 	return
 }
 
-func (b *MessagesBackend) UpdateMessage(user string, update *backend.MessageUpdate) (msg *backend.Message, err error) {
+func (b *Messages) UpdateMessage(user string, update *backend.MessageUpdate) (msg *backend.Message, err error) {
 	mailbox, uid, err := parseMessageId(update.Message.ID)
 	if err != nil {
 		return
@@ -547,7 +547,7 @@ func (b *MessagesBackend) UpdateMessage(user string, update *backend.MessageUpda
 	return
 }
 
-func (b *MessagesBackend) DeleteMessage(user, id string) (err error) {
+func (b *Messages) DeleteMessage(user, id string) (err error) {
 	mailbox, uid, err := parseMessageId(id)
 	if err != nil {
 		return
@@ -565,9 +565,9 @@ func (b *MessagesBackend) DeleteMessage(user, id string) (err error) {
 	return
 }
 
-func newMessagesBackend(conn *connBackend) backend.MessagesBackend {
-	return &MessagesBackend{
-		connBackend: conn,
+func newMessages(conns *conns) backend.MessagesBackend {
+	return &Messages{
+		conns: conns,
 		mailboxes: map[string][]*imap.MailboxInfo{},
 	}
 }