smtpd

type Client struct {
	HeloType   string
	HeloHost   string
	Pregreeted bool
	// contains filtered or unexported fields
}

type Connection interface {
	Addr() net.Addr
}

type Envelope struct {
	Client     Client
	Sender     MailAddress
	Recipients []MailAddress
	Data       []byte
}

type MailAddress string

type SMTPError string

type Server struct {
	Addr         string        // TCP address to listen on, ":25" if empty
	Hostname     string        // optional Hostname to announce; "" to use system hostname
	ReadTimeout  time.Duration // optional read timeout
	WriteTimeout time.Duration // optional write timeout

	// PregreetDelay is the amount of time to wait after sending the initial
	// "220-" line before sending the final "220 " line.
	PregreetDelay time.Duration

	// OnNewConnection, if non-nil, is called on new connections.
	// If it returns non-nil, the connection is closed.
	OnNewConnection func(c Connection) error

	// OnMailFrom, if non-nil, is called on MAIL FROM.
	// If the callback returns an SMTPError, the MAIL FROM address is not added
	// to the envelope, and the SMTPError is sent to the client as reply to
	// MAIL FROM.
	// If the callback returns a non-nil value that is not an SMTPError,
	// the address is also not added to the envelope, and the server replies
	// with "550 5.0.0 unacceptable sender" (permanent error).
	OnMailFrom func(c Connection, from MailAddress) error

	// OnRcptTo, if non-nil, is called on RCPT TO.
	// If it returns non-nil, the recipient is not rejected and not added
	// to the Envelope.
	// If the callback returns an SMTPError, the RCPT TO address is not added
	// to the envelope, and the SMTPError is sent to the client as reply to
	// MAIL FROM.
	// If the callback returns a non-nil value that is not an SMTPError,
	// the address is also not added to the envelope, and the server replies
	// with "550 5.0.0 unacceptable sender" (permanent error).
	OnRcptTo func(c Connection, rcpt MailAddress) error

	// Deliver is called when DATA is finished and the mail is ready to be
	// accepted. If it returns non-nil, the mail is rejected.
	Deliver func(env *Envelope) error

	// Log is used for logging within the Server.
	// If nil, logging is disabled.
	Log *log.Logger
}