Text.Parsec.Rfc2821

This module exports parser combinators for the grammar described in RFC2821, "Simple Mail Transfer Protocol", http://www.faqs.org/rfcs/rfc2821.html.

ESMTP State Machine

data SessionState

Constructors

Unknown

HaveHelo

HaveMailFrom

HaveRcptTo

HaveData

HaveQuit

Instances

Bounded SessionState

Methods

minBound :: SessionState

maxBound :: SessionState

Enum SessionState

Methods

succ :: SessionState -> SessionState

pred :: SessionState -> SessionState

toEnum :: Int -> SessionState

fromEnum :: SessionState -> Int

enumFrom :: SessionState -> [SessionState]

enumFromThen :: SessionState -> SessionState -> [SessionState]

enumFromTo :: SessionState -> SessionState -> [SessionState]

enumFromThenTo :: SessionState -> SessionState -> SessionState -> [SessionState]

Eq SessionState

Methods

(==) :: SessionState -> SessionState -> Bool

(/=) :: SessionState -> SessionState -> Bool

Ord SessionState

Methods

compare :: SessionState -> SessionState -> Ordering

(<) :: SessionState -> SessionState -> Bool

(<=) :: SessionState -> SessionState -> Bool

(>) :: SessionState -> SessionState -> Bool

(>=) :: SessionState -> SessionState -> Bool

max :: SessionState -> SessionState -> SessionState

min :: SessionState -> SessionState -> SessionState

Show SessionState

Methods

showsPrec :: Int -> SessionState -> ShowS

show :: SessionState -> String

showList :: [SessionState] -> ShowS

data Event

Constructors

Greeting

reserved for the user

SayHelo String

SayHeloAgain String

SayEhlo String

SayEhloAgain String

SetMailFrom Mailbox

AddRcptTo Mailbox

StartData

Deliver

reserved for the user

NeedHeloFirst

NeedMailFromFirst

NeedRcptToFirst

NotImplemened

Turn, Send, Soml, Saml, Vrfy, and Expn.

ResetState

SayOK

Triggered in case of Noop or when Rset is used before we even have a state.

SeeksHelp String

The parameter may be [].

Shutdown

SyntaxErrorIn String

Unrecognized String

Instances

Eq Event

Methods

(==) :: Event -> Event -> Bool

(/=) :: Event -> Event -> Bool

Show Event

Methods

showsPrec :: Int -> Event -> ShowS

show :: Event -> String

showList :: [Event] -> ShowS

type SmtpdFSM = State SessionState Event

smtpdFSM :: String -> SmtpdFSM

Parse a line of SMTP dialogue and run handleSmtpCmd to determine the Event. In case of syntax errors, SyntaxErrorIn or Unrecognized will be returned. Inputs must be terminated with crlf. See fixCRLF.

handleSmtpCmd :: SmtpCmd -> SmtpdFSM

For those who want to parse the SmtpCmd themselves. Calling this function in HaveQuit or HaveData will fail an assertion. If assert is disabled, it will return respectively Shutdown and StartData again.

Data Types for SMTP Commands

data SmtpCmd

The smtpCmd parser will create this data type from a string. Note that all command parsers expect their input to be terminated with crlf.

Constructors

Helo String

Ehlo String

MailFrom Mailbox

Might be nullPath.

RcptTo Mailbox

Might be postmaster.

Data

Rset

Send Mailbox

Soml Mailbox

Saml Mailbox

Vrfy String

Expn String

Help String

Might be [].

Noop

Optional argument ignored.

Quit

Turn

WrongArg String ParseError

When a valid command has been recognized, but the argument parser fails, then this type will be returned. The String contains the name of the command (in all upper-case) and the ParseError is, obviously, the error description.

Instances

Show SmtpCmd

Methods

showsPrec :: Int -> SmtpCmd -> ShowS

show :: SmtpCmd -> String

showList :: [SmtpCmd] -> ShowS

data Mailbox

The most general e-mail address has the form: <[@route,...:]user@domain>. This type, too, supports show and read. Note that a "shown" address is always enclosed in angular brackets. When comparing two mailboxes for equality, the hostname is case-insensitive.

Constructors

Mailbox [String] String String

Instances

Eq Mailbox

Methods

(==) :: Mailbox -> Mailbox -> Bool

(/=) :: Mailbox -> Mailbox -> Bool

Read Mailbox

Methods

readsPrec :: Int -> ReadS Mailbox

readList :: ReadS [Mailbox]

readPrec :: ReadPrec Mailbox

readListPrec :: ReadPrec [Mailbox]

Show Mailbox

Methods

showsPrec :: Int -> Mailbox -> ShowS

show :: Mailbox -> String

showList :: [Mailbox] -> ShowS

nullPath :: Mailbox

nullPath = Mailbox [] "" "" = "<>"

postmaster :: Mailbox

postmaster = Mailbox [] "postmaster" "" = "<postmaster>"

Data Types for SMTP Replies

data SmtpReply

An SMTP reply is a three-digit return code plus some waste of bandwidth called "comments". This is what the list of strings is for; one string per line in the reply. show will append an "\r\n" end-of-line marker to each entry in that list, so that the resulting string is ready to be sent back to the peer. For example:

>>> show $ Reply (Code Success MailSystem 0) ["worked", "like", "a charm" ]
"250-worked\r\n250-like\r\n250 a charm\r\n"

If the message is an empty list [], a default text will be constructed:

>>> show $ Reply (Code Success MailSystem 0) []
"250 Success in category MailSystem\r\n"

Constructors

Reply SmtpCode [String]

Instances

Show SmtpReply

Methods

showsPrec :: Int -> SmtpReply -> ShowS

show :: SmtpReply -> String

showList :: [SmtpReply] -> ShowS

data SmtpCode

Constructors

Code SuccessCode Category Int

Instances

Show SmtpCode

Methods

showsPrec :: Int -> SmtpCode -> ShowS

show :: SmtpCode -> String

showList :: [SmtpCode] -> ShowS

data SuccessCode

Constructors

Unused0

PreliminarySuccess

Success

IntermediateSuccess

TransientFailure

PermanentFailure

Instances

Bounded SuccessCode

Methods

minBound :: SuccessCode

maxBound :: SuccessCode

Enum SuccessCode

Methods

succ :: SuccessCode -> SuccessCode

pred :: SuccessCode -> SuccessCode

toEnum :: Int -> SuccessCode

fromEnum :: SuccessCode -> Int

enumFrom :: SuccessCode -> [SuccessCode]

enumFromThen :: SuccessCode -> SuccessCode -> [SuccessCode]

enumFromTo :: SuccessCode -> SuccessCode -> [SuccessCode]

enumFromThenTo :: SuccessCode -> SuccessCode -> SuccessCode -> [SuccessCode]

Eq SuccessCode

Methods

(==) :: SuccessCode -> SuccessCode -> Bool

(/=) :: SuccessCode -> SuccessCode -> Bool

Ord SuccessCode

Methods

compare :: SuccessCode -> SuccessCode -> Ordering

(<) :: SuccessCode -> SuccessCode -> Bool

(<=) :: SuccessCode -> SuccessCode -> Bool

(>) :: SuccessCode -> SuccessCode -> Bool

(>=) :: SuccessCode -> SuccessCode -> Bool

max :: SuccessCode -> SuccessCode -> SuccessCode

min :: SuccessCode -> SuccessCode -> SuccessCode

Show SuccessCode

Methods

showsPrec :: Int -> SuccessCode -> ShowS

show :: SuccessCode -> String

showList :: [SuccessCode] -> ShowS

data Category

Constructors

Syntax

Information

Connection

Unspecified3

Unspecified4

MailSystem

Instances

Bounded Category

Methods

minBound :: Category

maxBound :: Category

Enum Category

Methods

succ :: Category -> Category

pred :: Category -> Category

toEnum :: Int -> Category

fromEnum :: Category -> Int

enumFrom :: Category -> [Category]

enumFromThen :: Category -> Category -> [Category]

enumFromTo :: Category -> Category -> [Category]

enumFromThenTo :: Category -> Category -> Category -> [Category]

Eq Category

Methods

(==) :: Category -> Category -> Bool

(/=) :: Category -> Category -> Bool

Ord Category

Methods

compare :: Category -> Category -> Ordering

(<) :: Category -> Category -> Bool

(<=) :: Category -> Category -> Bool

(>) :: Category -> Category -> Bool

(>=) :: Category -> Category -> Bool

max :: Category -> Category -> Category

min :: Category -> Category -> Category

Show Category

Methods

showsPrec :: Int -> Category -> ShowS

show :: Category -> String

showList :: [Category] -> ShowS

reply :: Int -> Int -> Int -> [String] -> SmtpReply

Construct a Reply. Fails assert if invalid numbers are given.

isSuccess :: SmtpReply -> Bool

A reply constitutes "success" if the status code is any of PreliminarySuccess, Success, or IntermediateSuccess.

isFailure :: SmtpReply -> Bool

A reply constitutes "failure" if the status code is either PermanentFailure or TransientFailure.

isShutdown :: SmtpReply -> Bool

The replies 221 and 421 signify Shutdown.

Command Parsers

smtpCmd :: Stream s m Char => ParsecT s u m SmtpCmd

The SMTP parsers defined here correspond to the commands specified in RFC2821, so I won't document them individually.

This parser recognizes any of the SMTP commands defined below. Note that all command parsers expect their input to be terminated with crlf.

smtpData :: Stream s m Char => ParsecT s u m SmtpCmd

The parser name "data" was taken.

rset :: Stream s m Char => ParsecT s u m SmtpCmd

quit :: Stream s m Char => ParsecT s u m SmtpCmd

turn :: Stream s m Char => ParsecT s u m SmtpCmd

helo :: Stream s m Char => ParsecT s u m SmtpCmd

ehlo :: Stream s m Char => ParsecT s u m SmtpCmd

mail :: Stream s m Char => ParsecT s u m SmtpCmd

rcpt :: Stream s m Char => ParsecT s u m SmtpCmd

send :: Stream s m Char => ParsecT s u m SmtpCmd

soml :: Stream s m Char => ParsecT s u m SmtpCmd

saml :: Stream s m Char => ParsecT s u m SmtpCmd

vrfy :: Stream s m Char => ParsecT s u m SmtpCmd

expn :: Stream s m Char => ParsecT s u m SmtpCmd

help :: Stream s m Char => ParsecT s u m SmtpCmd

noop :: Stream s m Char => ParsecT s u m SmtpCmd

May have an optional word argument, but it is ignored.

Argument Parsers

from_path :: Stream s m Char => ParsecT s u m Mailbox

to_path :: Stream s m Char => ParsecT s u m Mailbox

path :: Stream s m Char => ParsecT s u m Mailbox

mailbox :: Stream s m Char => ParsecT s u m Mailbox

local_part :: Stream s m Char => ParsecT s u m String

domain :: Stream s m Char => ParsecT s u m String

a_d_l :: Stream s m Char => ParsecT s u m [String]

at_domain :: Stream s m Char => ParsecT s u m String

address_literal :: Stream s m Char => ParsecT s u m String

TODO: Add IPv6 address and general literals

ipv4_literal :: Stream s m Char => ParsecT s u m String

ipv4addr :: Stream s m Char => ParsecT s u m String

subdomain :: Stream s m Char => ParsecT s u m String

dot_string :: Stream s m Char => ParsecT s u m String

atom :: Stream s m Char => ParsecT s u m String

snum :: Stream s m Char => ParsecT s u m String

number :: Stream s m Char => ParsecT s u m String

word :: Stream s m Char => ParsecT s u m String

This is a useful addition: The parser accepts an atom or a quoted_string.

Helper Functions

fixCRLF :: String -> String

Make the string crlf terminated no matter what. '\n' is expanded, otherwise crlf is appended. Note that if the string was terminated incorrectly before, it still is. This function is useful when reading input with hGetLine which removes the end-of-line delimiter.

mkCmd0 :: Stream s m Char => String -> a -> ParsecT s u m a

Construct a parser for a command without arguments. Expects crlf!

mkCmd1 :: Stream s m Char => String -> (a -> SmtpCmd) -> ParsecT s u m a -> ParsecT s u m SmtpCmd

Construct a parser for a command with an argument, which the given parser will handle. The result of the argument parser will be applied to the type constructor before it is returned. Expects crlf!

tokenList :: Stream s m Char => ParsecT s u m String -> Char -> ParsecT s u m String