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A lightweight and very fast base64 encoder and decoder.

License

Unknown, MIT licenses found

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MIT
LICENSE.md
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extendr/b64

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b64 is a dependency free, fast, lightweight, and vectorized base64encoder and decoder.

Installation

You can install b64 from CRAN with

install.packages("b64")

Example

Encode to base64 usingencode().

library(b64)hello<- encode("Hello, from extendr")hello#> [1] "SGVsbG8sIGZyb20gZXh0ZW5kcg=="

Decode usingdecode(). Note that the returned object will always havethe"blob" class. To achieve 0 dependencies, theblob package isonly listed as a suggested dependency but if you attach it, its printmethod will be used.

library(blob)decoded<- decode(hello)decoded#> <blob[1]>#> [1] blob[19 B]

We can convert the decoded base64 to characters and see how it worked.

rawToChar(decoded[[1]])#> [1] "Hello, from extendr"

Vectorized

Bothencode() anddecode() are vectorized.

lorem<- unlist(lorem::ipsum(5,1,5))lorem#> [1] "Consectetur in sapien interdum diam lobortis eros?"#> [2] "Lorem sed ligula fames?"#> [3] "Adipiscing suscipit magna sapien varius."#> [4] "Elit tellus taciti turpis hendrerit sagittis."#> [5] "Sit suspendisse ultrices augue class parturient ultricies venenatis."encoded<- encode(lorem)encoded#> [1] "Q29uc2VjdGV0dXIgaW4gc2FwaWVuIGludGVyZHVtIGRpYW0gbG9ib3J0aXMgZXJvcz8="#> [2] "TG9yZW0gc2VkIGxpZ3VsYSBmYW1lcz8="#> [3] "QWRpcGlzY2luZyBzdXNjaXBpdCBtYWduYSBzYXBpZW4gdmFyaXVzLg=="#> [4] "RWxpdCB0ZWxsdXMgdGFjaXRpIHR1cnBpcyBoZW5kcmVyaXQgc2FnaXR0aXMu"#> [5] "U2l0IHN1c3BlbmRpc3NlIHVsdHJpY2VzIGF1Z3VlIGNsYXNzIHBhcnR1cmllbnQgdWx0cmljaWVzIHZlbmVuYXRpcy4="

We can decode all of these usingdecode() as well.

decode(encoded)#> <blob[5]>#> [1] blob[50 B] blob[23 B] blob[40 B] blob[45 B] blob[68 B]

Encoding and decoding files

b64 shines when encoding and decoding files.encode_file() anddecode_file() both work by reading a file as a stream making it farfaster than the alternative.

tmp<- tempfile()fp<-"https://github.com/extendr/b64/blob/main/src/rust/vendor.tar.xz"download.file(fp,tmp)bench::mark(b64= encode_file(tmp),base64enc=base64enc::base64encode(tmp))#> # A tibble: 2 × 6#>   expression      min   median `itr/sec` mem_alloc `gc/sec`#>   <bch:expr> <bch:tm> <bch:tm>     <dbl> <bch:byt>    <dbl>#> 1 b64           334µs    340µs     2810.     218KB     0#> 2 base64enc     905µs    938µs     1043.     729KB     4.22

While the encoding is very impressive, better yet is the decodingperformance.

# create a temp filetmp2<- tempfile()# encode it and write to tmep fileencode_file(tmp)|>  charToRaw()|>  writeBin(tmp2)bench::mark(b64= decode_file(tmp2),base64enc=base64enc::base64decode(file(tmp2)))#> # A tibble: 2 × 6#>   expression      min   median `itr/sec` mem_alloc `gc/sec`#>   <bch:expr> <bch:tm> <bch:tm>     <dbl> <bch:byt>    <dbl>#> 1 b64        107.09µs  122.6µs     7414.     164KB     8.77#> 2 base64enc    1.58ms    1.6ms      602.     172KB     3.70

Alternative engines

Out of the box,b64 provides a number of pre-configured engines thatcan be used. The functionengine() allows you to choose one of thesedifferent engines For example,engine("url_safe") provides a standardengine that uses a url-safe alphabet with padding.

url_engine<- engine("url_safe")url_safe_encoded<- encode("\xfa\xec U",url_engine)url_safe_encoded#> [1] "-uwgVQ=="

If we try to decode this using the standard engine, we will encounter anerror.

decode(url_safe_encoded)#> Error in decode_(what, eng): Invalid byte 45, offset 0.

We can use our new engine to decode it.

decode(url_safe_encoded,url_engine)#> <blob[1]>#> [1] blob[4 B]

Custom Engines

We can create custom engines withnew_engine(). This allows us toprovide our on alphabet and configuration.

We can use one of the many predefined alphabets or create one our selveswithnew_alphabet(). We can also specify our engine config usingnew_config() which lets us choose whether or not to pad and how tohandle decoding.

my_eng<- new_engine(  alphabet("crypt"),  new_config(TRUE,TRUE,"none"))

This engine can be used to encode or decode text.

txt<-"lorem ipsum sit dolor amet"encode(txt,my_eng)#> [1] "P4xmNKoUOL/nRKoUQqZo64FjP4xm643hNLE="

Compare this to the standard encoder:

encode(txt)#> [1] "bG9yZW0gaXBzdW0gc2l0IGRvbG9yIGFtZXQ="

About

A lightweight and very fast base64 encoder and decoder.

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License

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MIT
LICENSE.md

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