+++ /dev/null
-{-# LANGUAGE
- UnicodeSyntax
- #-}
--- |This module provides functions to parse and format HTTP\/1.1 date
--- and time formats.
---
--- The HTTP\/1.1 specification (RFC 2616) says that HTTP\/1.1 clients
--- and servers which parse the date value MUST accept all the
--- following formats, though they MUST only generate the RFC 1123
--- format for representing HTTP-date values in header fields:
---
--- > Sun, 06 Nov 1994 08:49:37 GMT ; RFC 822, updated by RFC 1123
--- > Sunday, 06-Nov-94 08:49:37 GMT ; RFC 850, obsoleted by RFC 1036
--- > Sun Nov 6 08:49:37 1994 ; ANSI C's asctime() format
---
--- It also says that all HTTP date\/time stamps MUST be represented in
--- Greenwich Mean Time (GMT), without exception. For the purposes of
--- HTTP, GMT is exactly equal to UTC (Coordinated Universal
--- Time). This is indicated in the first two formats by the inclusion
--- of @\"GMT\"@ as the three-letter abbreviation for time zone, and
--- MUST be assumed when reading the asctime format.
---
--- > HTTP-date = rfc1123-date | rfc850-date | asctime-date
--- > rfc1123-date = wkday "," SP date1 SP time SP "GMT"
--- > rfc850-date = weekday "," SP date2 SP time SP "GMT"
--- > asctime-date = wkday SP date3 SP time SP 4DIGIT
--- > date1 = 2DIGIT SP month SP 4DIGIT
--- > ; day month year (e.g., 02 Jun 1982)
--- > date2 = 2DIGIT "-" month "-" 2DIGIT
--- > ; day-month-year (e.g., 02-Jun-82)
--- > date3 = month SP ( 2DIGIT | ( SP 1DIGIT ))
--- > ; month day (e.g., Jun 2)
--- > time = 2DIGIT ":" 2DIGIT ":" 2DIGIT
--- > ; 00:00:00 - 23:59:59
--- > wkday = "Mon" | "Tue" | "Wed"
--- > | "Thu" | "Fri" | "Sat" | "Sun"
--- > weekday = "Monday" | "Tuesday" | "Wednesday"
--- > | "Thursday" | "Friday" | "Saturday" | "Sunday"
--- > month = "Jan" | "Feb" | "Mar" | "Apr"
--- > | "May" | "Jun" | "Jul" | "Aug"
--- > | "Sep" | "Oct" | "Nov" | "Dec"
-module Data.Time.HTTP
- ( -- * Formatting
- toAscii
- , toAsciiBuilder
-
- -- * Parsing
- , fromAscii
- , httpDateAndTime
- )
- where
-import Data.Ascii (Ascii)
-import qualified Data.Ascii as A
-import qualified Data.Attoparsec.Char8 as P
-import Data.Time
-import Data.Time.HTTP.Internal
-import Prelude.Unicode
-
--- |Convert a 'UTCTime' to RFC 1123 date and time string.
-toAscii ∷ UTCTime → Ascii
-toAscii = A.fromAsciiBuilder ∘ toAsciiBuilder
-
--- |Parse a date and time string in any of RFC 822, RFC 1123, RFC 850
--- and ANSI C's asctime() formats. When the string can't be parsed, it
--- returns @'Left' err@.
---
--- This function is even more permissive than what HTTP\/1.1
--- specifies. That is, it accepts 2-digit years in RFC 822, omitted
--- separator symbols in RFC 850, omitted sec fields, and non-GMT time
--- zones. I believe this behavior will not cause a problem but you
--- should know this.
-fromAscii ∷ Ascii → Either String UTCTime
-fromAscii = P.parseOnly p ∘ A.toByteString
- where
- p = do zt ← httpDateAndTime
- P.endOfInput
- return zt