Copyright | (c) 2019-2023 Emily Pillmore |
---|---|
License | BSD-style |
Maintainer | Emily Pillmore <emilypi@cohomolo.gy> |
Stability | stable |
Portability | non-portable |
Safe Haskell | Safe-Inferred |
Language | Haskell2010 |
This module contains Text
-valued combinators for
implementing the RFC 4648 specification of the Base64
encoding format. This includes lenient decoding variants, as well as
internal and external validation for canonicity.
Synopsis
- encodeBase64 :: Text -> Base64 'StdPadded Text
- decodeBase64 :: StdAlphabet k => Base64 k Text -> Text
- decodeBase64Untyped :: Text -> Either Text Text
- decodeBase64UntypedWith :: (ByteString -> Either err Text) -> ByteString -> Either (Base64Error err) Text
- decodeBase64Lenient :: Text -> Text
- isBase64 :: Text -> Bool
- isValidBase64 :: Text -> Bool
Encoding
encodeBase64 :: Text -> Base64 'StdPadded Text Source #
Encode a Text
value in Base64 with padding.
See: RFC-4648 section 4
Examples:
>>>
encodeBase64 "Sun"
"U3Vu"
Decoding
decodeBase64 :: StdAlphabet k => Base64 k Text -> Text Source #
Decode a padded Base64-encoded Text
value.
See: RFC-4648 section 4
Examples:
>>>
decodeBase64 $ assertBase64 @'StdPadded "U3Vu"
"Sun"
decodeBase64Untyped :: Text -> Either Text Text Source #
Decode a padded, untyped Base64-encoded Text
value.
See: RFC-4648 section 4
Examples:
>>>
decodeBase64Untyped "U3Vu"
Right "Sun"
decodeBase64UntypedWith Source #
:: (ByteString -> Either err Text) | convert a bytestring to text (e.g. |
-> ByteString | Input text to decode |
-> Either (Base64Error err) Text |
Attempt to decode an untyped Text
value as Base64, converting from
ByteString
to Text
according to some encoding function. In practice,
This is something like decodeUtf8'
, which may produce an error.
See: RFC-4648 section 4
Example:
decodeBase64UntypedWith
decodeUtf8'
::ByteString
->Either
(Base64Error
UnicodeException
)Text
decodeBase64Lenient :: Text -> Text Source #
Leniently decode an untyped Base64-encoded Text
value. This function
will not generate parse errors. If input data contains padding chars,
then the input will be parsed up until the first pad character.
Note: This is not RFC 4648-compliant.
Examples:
>>>
decodeBase64Lenient "U3Vu"
"Sun"
>>>
decodeBase64Lenient "U3V"
"Su"
>>>
decodeBase64Lenient "U3V="
"Su"
Validation
isBase64 :: Text -> Bool Source #
Tell whether an untyped Text
value is Base64-encoded.
Examples:
>>>
isBase64 "U3Vu"
True
>>>
isBase64 "U3V"
False
>>>
isBase64 "U3V="
False
isValidBase64 :: Text -> Bool Source #
Tell whether an untyped Text
value is a valid Base64 format.
This will not tell you whether or not this is a correct Base64 representation,
only that it conforms to the correct shape. To check whether it is a true
Base64 encoded Text
value, use isBase64
.
Examples:
>>>
isValidBase64 "U3Vu"
True
>>>
isValidBase64 "U3V"
True
>>>
isValidBase64 "U3V="
True
>>>
isValidBase64 "%"
False