Unzip a file that was embedded in the Rust application

The rocket-starter crate includes several sets of files, each one is a skeleton to start writing a Rocket-based web application in Rust.

In another article we saw how to extract the content of a tar.gz file on the disk and it turns out the code is almost exactly the same in this case as well.

The difference is that we use the bufread::GzDecoder instead of the read::GzDecoder

There is a file called example.tar.gz in the root of the crate.

In order to embed that tar.gz file in the executable binary we use the include_bytes! macro.

let zipped = include_bytes!("../example.tar.gz");

We use the flate2 to uncompress the stored bytes and the the tar crate to separate it into individual files.

Dependencies

examples/unzip-from-memory/Cargo.toml

[package]
name = "unzip-file"
version = "0.1.0"
edition = "2021"

[dependencies]
flate2 = "1.0.30"
tar = "0.4.40"

Full example unzipping a file to the disk

examples/unzip-from-memory/src/main.rs

use std::{error::Error, fs::create_dir_all, path::PathBuf};

use flate2::bufread::GzDecoder;
use tar::Archive;

fn main() {
    let folder = PathBuf::from("data");
    let zipped = include_bytes!("../example.tar.gz");

    if !folder.exists() {
        create_dir_all(&folder).unwrap()
    }

    unzip(zipped, folder).unwrap();
}

fn unzip(tar_gz: &[u8], folder: PathBuf) -> Result<(), Box<dyn Error>> {
    println!("Unzipping to {folder:?}");

    let tar = GzDecoder::new(tar_gz);
    let mut archive = Archive::new(tar);
    archive.unpack(folder)?;

    Ok(())
}