base64-0.4.2: Fast RFC 4648-compliant Base64 encoding

Copyright (c) 2019-2020 Emily Pillmore BSD-style Emily Pillmore Experimental portable None Haskell2010

Data.Text.Lazy.Encoding.Base64.URL

Description

This module contains the combinators implementing the RFC 4648 specification for the Base64-URL encoding including unpadded and lenient variants

Synopsis

Documentation

encodeBase64 :: Text -> Text Source #

Encode a Text value in Base64url with padding.

decodeBase64 :: Text -> Either Text Text Source #

Decode a padded Base64url-encoded Text 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 base64url encodings are optionally padded.

For a decoder that fails on unpadded input, use decodeBase64Unpadded.

Note: This function makes sure that decoding is total by deferring to decodeLatin1. This will always round trip for any valid Base64-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 decodeBase64With and pass in a custom decode function.

Arguments

 :: (ByteString -> Either err Text) convert a bytestring to text (e.g. decodeUtf8') -> ByteString Input text to decode -> Either (Base64Error err) Text

Attempt to decode a lazy ByteString value as Base64url, converting from ByteString to Text according to some encoding function. In practice, This is something like decodeUtf8', which may produce an error.

Example:

decodeBase64With decodeUtf8'
:: ByteString -> Either (Base64Error UnicodeException) Text


encodeBase64Unpadded :: Text -> Text Source #

Encode a Text value in Base64url without padding. Note that for Base64url, padding is optional. If you call this function, you will simply be encoding as Base64url and stripping padding chars from the output.

decodeBase64Unpadded :: Text -> Either Text Text Source #

Decode an unpadded Base64url encoded Text value.

Note: This function makes sure that decoding is total by deferring to decodeLatin1. This will always round trip for any valid Base64-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 decodeBase64WUnpaddedWith and pass in a custom decode function.

Arguments

 :: (ByteString -> Either err Text) convert a bytestring to text (e.g. decodeUtf8') -> ByteString Input text to decode -> Either (Base64Error err) Text

Attempt to decode an unpadded lazy ByteString value as Base64url, converting from ByteString to Text according to some encoding function. In practice, This is something like decodeUtf8', which may produce an error.

Example:

decodeBase64With decodeUtf8'
:: ByteString -> Either (Base64Error UnicodeException) Text


decodeBase64Padded :: Text -> Either Text Text Source #

Decode an padded Base64url encoded Text value

Note: This function makes sure that decoding is total by deferring to decodeLatin1. This will always round trip for any valid Base64-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 decodeBase64PaddedWith and pass in a custom decode function.

Arguments

 :: (ByteString -> Either err Text) convert a bytestring to text (e.g. decodeUtf8') -> ByteString Input text to decode -> Either (Base64Error err) Text

Attempt to decode a padded lazy ByteString value as Base64url, converting from ByteString to Text according to some encoding function. In practice, This is something like decodeUtf8', which may produce an error.

Example:

decodeBase64With decodeUtf8'
:: ByteString -> Either (Base64Error UnicodeException) Text


decodeBase64Lenient :: Text -> Text Source #

Leniently decode an unpadded Base64url-encoded Text. 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.

isBase64Url :: Text -> Bool Source #

Tell whether a Text value is Base64url-encoded.

isValidBase64Url :: Text -> Bool Source #

Tell whether a Text value is a valid Base64url format.

This will not tell you whether or not this is a correct Base64url representation, only that it conforms to the correct shape. To check whether it is a true Base64 encoded Text value, use isBase64Url.