具有Docker构建的Cache Rust依赖项

Question

我在Rust + Actix-web中有hello世界网络项目。我有几个问题。首先是代码的每次更改都会导致重新编译整个项目，包括下载和编译每个板条箱。我想像正常开发一样工作-这意味着缓存已编译的板条箱，仅重新编译我的代码库。第二个问题是它不会暴露我的应用程序。通过网络浏览器无法访问

Dockerfile：

FROM rust

WORKDIR /var/www/app

COPY . .

EXPOSE 8080

RUN cargo run

docker-compose.yml：

version: "3"
services:
  app:
    container_name: hello-world
    build: .
    ports:
      - '8080:8080'
    volumes:
      - .:/var/www/app
      - registry:/root/.cargo/registry

volumes:
  registry:
    driver: local

main.rs：

extern crate actix_web;

use actix_web::{web, App, HttpServer, Responder};

fn index() -> impl Responder {
    "Hello world"
}

fn main() -> std::io::Result<()> {
    HttpServer::new(|| App::new().service(web::resource("/").to(index)))
        .bind("0.0.0.0:8080")?
        .run()
}

Cargo.toml：

[package]
name = "hello-world"
version = "0.1.0"
authors = []
edition = "2018"

[dependencies]
actix-web = "1.0"

Answer 1

似乎您并不孤单地通过docker build过程来缓存rust依赖项。这是一篇很棒的文章，可以一路为您提供帮助：https://blog.mgattozzi.dev/caching-rust-docker-builds/

其要点是，您首先需要一个dummy.rs和您的Cargo.toml，然后构建它以缓存依赖项，然后再复制您的应用程序源，以免每次构建都使缓存无效。

Dockerfile

FROM rust
WORKDIR /var/www/app
COPY dummy.rs .
COPY Cargo.toml .
RUN sed -i 's#src/main.rs#dummy.rs#' Cargo.toml
RUN cargo build --release
RUN sed -i 's#dummy.rs#src/main.rs#' Cargo.toml
COPY . .
RUN cargo build --release
CMD ["target/release/app"]

CMD应用程序名称“ app”基于您在Cargo.toml中为二进制文件指定的名称。

dummy.rs

fn main() {}

Cargo.toml

[package]
name = "app"
version = "0.1.0"
authors = ["..."]
[[bin]]
name = "app"
path = "src/main.rs"

[dependencies]
actix-web = "1.0.0"

src / main.rs

extern crate actix_web;

use actix_web::{web, App, HttpServer, Responder};

fn index() -> impl Responder {
    "Hello world"
}

fn main() -> std::io::Result<()> {
    HttpServer::new(|| App::new().service(web::resource("/").to(index)))
        .bind("0.0.0.0:8080")?
        .run()
}