Day: December 13, 2021

Create statically linked rust docker image with alpine

Why?
– Optimize size
– less surface attack

FROM rust:slim-buster AS build
WORKDIR /opt
COPY . .
RUN rustup target add x86_64-unknown-linux-musl
RUN cargo build --target x86_64-unknown-linux-musl --release

FROM alpine:3.15.0
WORKDIR /opt
COPY --from=build /opt/target/x86_64-unknown-linux-musl/release .
EXPOSE 7878
CMD ["/opt/simple-rust-webserver"]
docker build -t rust-web-alpine -f alpine.Dockerfile .

docker run -d -p 7878:7878 rust-web-alpine
[root@lp-test-1 simple-rust-webserver]# docker images | grep rust-web-alpine
rust-web-alpine                                latest          7dd00663078c   9 minutes ago    9.4MB

main.rs

use std::net::{TcpStream, TcpListener};
use std::io::{Read, Write};
use std::thread;


fn handle_read(mut stream: &TcpStream) {
    let mut buf = [0u8 ;4096];
    match stream.read(&mut buf) {
        Ok(_) => {
            let req_str = String::from_utf8_lossy(&buf);
            println!("{}", req_str);
            },
        Err(e) => println!("Unable to read stream: {}", e),
    }
}

fn handle_write(mut stream: TcpStream) {
    let response = b"HTTP/1.1 200 OK\r\nContent-Type: text/html; charset=UTF-8\r\n\r\n<html><body>hola rust</body></html>\r\n";
    match stream.write(response) {
        Ok(_) => println!("Response sent"),
        Err(e) => println!("Failed sending response: {}", e),
    }
}

fn handle_client(stream: TcpStream) {
    handle_read(&stream);
    handle_write(stream);
}

fn main() {
    let listener = TcpListener::bind("0.0.0.0:7878").unwrap();
    println!("Listening for connections on port {}", 7878);

    for stream in listener.incoming() {
        match stream {
            Ok(stream) => {
                thread::spawn(|| {
                    handle_client(stream)
                });
            }
            Err(e) => {
                println!("Unable to connect: {}", e);
            }
        }
    }
}

More : https://users.rust-lang.org/t/building-executable-for-alpine-linux/13568

https://doc.rust-lang.org/cargo/commands/cargo-build.html