Copyright | (c) 2019-2020 Emily Pillmore |
---|---|
License | BSD-style |
Maintainer | Emily Pillmore <emilypi@cohomolo.gy> |
Stability | stable |
Portability | non-portable |
Safe Haskell | Trustworthy |
Language | Haskell2010 |
This module contains ShortText
-valued combinators
implementing the RFC 4648 specification for the Base32
encoding format. This includes strictly padded/unpadded decoding
variants, and external + internal validations for canonicity.
Synopsis
- encodeBase32 :: ShortText -> ShortText
- encodeBase32Unpadded :: ShortText -> ShortText
- decodeBase32 :: ShortText -> Either Text ShortText
- decodeBase32With :: (ShortByteString -> Either err ShortText) -> ShortByteString -> Either (Base32Error err) ShortText
- decodeBase32Unpadded :: ShortText -> Either Text ShortText
- decodeBase32UnpaddedWith :: (ShortByteString -> Either err ShortText) -> ShortByteString -> Either (Base32Error err) ShortText
- decodeBase32Padded :: ShortText -> Either Text ShortText
- decodeBase32PaddedWith :: (ShortByteString -> Either err ShortText) -> ShortByteString -> Either (Base32Error err) ShortText
- isBase32 :: ShortText -> Bool
- isValidBase32 :: ShortText -> Bool
Encoding
encodeBase32 :: ShortText -> ShortText Source #
Encode a ShortText
value in Base32 with padding.
See: RFC-4328 section 6
Examples:
>>>
encodeBase32 "Sun"
"KN2W4==="
encodeBase32Unpadded :: ShortText -> ShortText Source #
Encode a ShortText
value in Base32 without padding. Note that for Base32,
padding is optional. If you call this function, you will simply be encoding
as Base32 and stripping padding chars from the output.
See: RFC-4328 section 6
Examples:
>>>
encodeBase32Unpadded "Sun"
"KN2W4"
Decoding
decodeBase32 :: ShortText -> Either Text ShortText Source #
Decode an arbitrarily padded Base32-encoded ShortText
value. If its length is not a multiple
of 4, then padding chars will be added to fill out the input to a multiple of
4 for safe decoding as base32 encodings are optionally padded.
Note: This function makes sure that decoding is total by deferring to
decodeLatin1
. This will always round trip for any valid Base32-encoded
text value, but it may not round trip for bad inputs. The onus is on the
caller to make sure inputs are valid. If unsure, defer to decodeBase32With
and pass in a custom decode function.
See: RFC-4328 section 6
Examples:
>>>
decodeBase32 "KN2W4==="
Right "Sun"
>>>
decodeBase32 "KN2W4"
Right "Sun"
>>>
decodeBase32 "KN2W==="
Left "Base32-encoded bytestring has invalid padding"
:: (ShortByteString -> Either err ShortText) | convert a bytestring to text (e.g. |
-> ShortByteString | Input text to decode |
-> Either (Base32Error err) ShortText |
Attempt to decode a ShortByteString
value as Base32, converting from
ByteString
to ShortText
according to some encoding function. In practice,
This is something like decodeUtf8'
, which may produce an error.
See: RFC-4328 section 6
Examples:
decodeBase32With
'(fmap fromText . T.decodeUtf8' . toText)' ::ShortByteString
->Either
(Base32Error
UnicodeException
)ShortText
decodeBase32Unpadded :: ShortText -> Either Text ShortText Source #
Decode an unpadded Base32 encoded ShortText
value.
Note: This function makes sure that decoding is total by deferring to
decodeLatin1
. This will always round trip for any valid Base32-encoded
text value, but it may not round trip for bad inputs. The onus is on the
caller to make sure inputs are valid. If unsure, defer to decodeBase32UnpaddedWith
and pass in a custom decode function.
See: RFC-4328 section 6
Examples:
>>>
decodeBase32Unpadded "KN2W4"
Right "Sun"
>>>
decodeBase32Unpadded "KN2W4==="
Left "Base32-encoded bytestring has invalid padding"
decodeBase32UnpaddedWith Source #
:: (ShortByteString -> Either err ShortText) | convert a bytestring to text (e.g. |
-> ShortByteString | Input text to decode |
-> Either (Base32Error err) ShortText |
Attempt to decode an unpadded ShortByteString
value as Base32, converting from
ShortByteString
to ShortText
according to some encoding function. In practice,
This is something like decodeUtf8'
, which may produce an error.
See: RFC-4328 section 6
Examples:
decodeBase32UnpaddedWith
'(fmap fromText . T.decodeUtf8' . toText)' ::ShortByteString
->Either
(Base32Error
UnicodeException
)ShortText
decodeBase32Padded :: ShortText -> Either Text ShortText Source #
Decode an padded Base32 encoded ShortText
value
Note: This function makes sure that decoding is total by deferring to
decodeLatin1
. This will always round trip for any valid Base32-encoded
text value, but it may not round trip for bad inputs. The onus is on the
caller to make sure inputs are valid. If unsure, defer to decodeBase32PaddedWith
and pass in a custom decode function.
See: RFC-4328 section 6
Examples:
>>>
decodeBase32Padded "KN2W4==="
Right "Sun"
>>>
decodeBase32Padded "KN2W4"
Left "Base32-encoded bytestring requires padding"
decodeBase32PaddedWith Source #
:: (ShortByteString -> Either err ShortText) | convert a bytestring to text (e.g. |
-> ShortByteString | Input text to decode |
-> Either (Base32Error err) ShortText |
Attempt to decode a padded ShortByteString
value as Base32, converting from
ByteString
to ShortText
according to some encoding function. In practice,
This is something like decodeUtf8'
, which may produce an error.
See: RFC-4328 section 6
Examples:
decodeBase32With
'(fmap fromText . T.decodeUtf8' . toText)' ::ShortByteString
->Either
(Base32Error
UnicodeException
)ShortText
Validation
isBase32 :: ShortText -> Bool Source #
Tell whether a ShortText
value is Base32-encoded.
Examples:
>>>
isBase32 "KN2W4"
True
>>>
isBase32 "KN2W4==="
True
>>>
isBase32 "KN2W4=="
False
isValidBase32 :: ShortText -> Bool Source #
Tell whether a ShortText
value is a valid Base32 format.
This will not tell you whether or not this is a correct Base32 representation,
only that it conforms to the correct shape. To check whether it is a true
Base32 encoded ShortText
value, use isBase32
.
Examples:
>>>
isValidBase32 "KN2W4"
True
>>>
isValidBase32 "KN2W4="
False
>>>
isValidBase32 "KN2W4%"
False