shell-download

A zero-dependency Rust library for downloading a URL to a file by delegating to whatever download tools are available on the current system.

It hunts for (in order): curl, wget, pwsh/powershell, and finally openssl (HTTPS via openssl s_client, HTTP via a raw TCP GET).

• The caller provides a target path.
• That file is unlinked before the request starts.
• The response body is written to that path (decompressed if the response is gzip).
• The request runs in a background thread and returns a cancellable handle.

Features

By default, these features are not enabled, making the crate zero-dependency.

• url: Parse URLs using the url crate (adds a number of dependencies, but makes URL parsing more accurate).
• in-memory: Receive the response body as a String or Vec instead of requiring a path. Uses the tempfile crate.

Usage

use shell_download::{Downloader, RequestBuilder};

fn main() -> Result<(), shell_download::Error> {
    let out = std::path::Path::new("downloaded.json");

    let handle = RequestBuilder::new("https://httpbin.org/redirect/5")
        .header("User-Agent", "shell-download/0.1")
        .follow_redirects(true)
        // Optional: force a specific backend (useful for tests)
        .preferred_downloader(Downloader::Curl)
        .start(out)?;

    // Optional: cancel from another thread if you need to abort
    // handle.cancel();

    let response = handle.join()?;
    println!("status={}", response.status_code);

    let body = std::fs::read_to_string(out).unwrap();
    assert!(body.contains("httpbin.org/get"));

    Ok(())
}