take_bytes

A lightweight Rust utility for reading input from stdin or a file path, designed for seamless integration with clap's derive API.

Features

• Simple API: Just parse "-" for stdin or any path for file input
• Clap Integration: Implements FromStr for direct use as a clap argument type
• Zero Configuration: Works out of the box with sensible defaults
• Lightweight: Minimal dependencies

Installation

Add this to your Cargo.toml:

[dependencies]
take_bytes = "0.1"

The clap feature is enabled by default. To use without clap:

[dependencies]
take_bytes = { version = "0.1", default-features = false }

Usage

With Clap

use clap::Parser;
use take_bytes::TakeBytes;

#[derive(Parser)]
struct Cli {
    /// Input file or "-" for stdin
    #[arg(default_value = "-")]
    input: TakeBytes,
}

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let cli = Cli::parse();
    
    // Read as bytes
    let bytes = cli.input.try_into_bytes()?;
    println!("Read {} bytes", bytes.len());
    
    Ok(())
}

Programmatic Use

use take_bytes::TakeBytes;
use std::path::PathBuf;

// Read from stdin
let stdin_input = TakeBytes::stdin();

// Read from a file
let file_input = TakeBytes::file(PathBuf::from("input.txt"));

// Parse from string (like clap does)
let input: TakeBytes = "-".parse()?;

Helper Functions

use take_bytes::{TakeBytes, read_as_bytes, decode_utf8_string};

let input: TakeBytes = "file.txt".parse()?;

// Read as raw bytes
let bytes = read_as_bytes(input)?;

// Or decode as UTF-8 string
let input: TakeBytes = "file.txt".parse()?;
let text = decode_utf8_string(input)?;

Examples

The classic Unix pattern of accepting input from either a file or stdin:

# Read from a file
myapp input.txt

# Read from stdin
cat input.txt | myapp -

# Read from stdin (default)
echo "hello" | myapp

License

MIT License - see LICENSE for details.