binary_macros_impl 1.0.0

Procedural macro implementations for decoding base64-like encodings in string literals to [u8] literals.
Documentation
extern crate data_encoding;
extern crate proc_macro_hack;
extern crate proc_macro;
extern crate dotenv;

use std::str::FromStr;
use std::io::Read;
use proc_macro_hack::proc_macro_hack;
use proc_macro::TokenStream;

fn helper(input: TokenStream, decoder: data_encoding::Encoding) -> TokenStream
{
    let input = input.to_string();
    let input = input.trim_matches('"');

    let byte_vec = if input.starts_with("file:") {

        let mut file = std::fs::File::open(&input[5..]).expect("Error opening file");
        let mut contents = String::new();
        file.read_to_string(&mut contents).expect("Error reading file");
        decoder.decode(contents.trim().as_bytes()).expect("Parse error")

    } else if input.starts_with("env:") {

        dotenv::dotenv().ok();
        let var = std::env::var(&input[4..]).expect("Error reading environment variable");
        decoder.decode(var.as_bytes()).expect("Parse error")

    } else {

        decoder.decode(input.as_bytes()).expect("Parse error")

    };

    TokenStream::from_str(&format!("{{static _BIN: [u8; {}] = {:?}; &_BIN}}", byte_vec.len(), byte_vec)).expect("Parse error")
}


#[proc_macro_hack]
pub fn base16(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::HEXLOWER)
}

#[proc_macro_hack]
pub fn base32hex(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE32HEX)
}

#[proc_macro_hack]
pub fn base32(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE32)
}

#[proc_macro_hack]
pub fn base64(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE64)
}

#[proc_macro_hack]
pub fn base64url(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE64URL)
}



#[proc_macro_hack]
pub fn base32hex_nopad(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE32HEX_NOPAD)
}

#[proc_macro_hack]
pub fn base32_nopad(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE32_NOPAD)
}

#[proc_macro_hack]
pub fn base64_nopad(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE64_NOPAD)
}

#[proc_macro_hack]
pub fn base64url_nopad(input: TokenStream) -> TokenStream {
    helper(input, data_encoding::BASE64URL_NOPAD)
}