Package backendutil provides utility functions to implement IMAP backends.

A memory backend.

NewUpdate creates a new update.

ErrInvalidCredentials is returned by Backend.Login when a username or a password is incorrect.

ErrMailboxAlreadyExists is returned by User.CreateMailbox and User.RenameMailbox when creating or renaming mailbox that already exists.

ErrNoSuchMailbox is returned by User.GetMailbox, User.DeleteMailbox and User.RenameMailbox when retrieving, deleting or renaming a mailbox that doesn't exist.

ExpungeUpdate is an expunge update.

MailboxUpdate is a mailbox update.

MessageUpdate is a message update.

StatusUpdate is a status update.

Backend is an IMAP server backend.

BackendUpdater is a Backend that implements Updater is able to send unilateral backend updates.

Mailbox represents a mailbox belonging to a user in the mail storage system.

MailboxPoller is a Mailbox that is able to poll updates for new messages or message status updates during a period of inactivity.

Update contains user and mailbox information about an unilateral backend update.

User represents a user in the mail storage system.