如何使用 Cargo 构建多个二进制文件？

Question

I'd like to make a project with a daemon and a client , connecting through a unix socket.

A client and a daemon requires two binaries, so how do I tell Cargo to build two targets from two different sources?

To add a bit of fantasy, I'd like to have a library for the main part of the daemon , and just have a binary to wrap around it and communicate through sockets.

So, we have this kind of tree architecture:

├── Cargo.toml
├── target
|   └── debug
|       ├── daemon
│       └── client
└── src
    ├── daemon
    │   ├── bin
    │   │   └── main.rs
    │   └── lib
    │       └── lib.rs
    └── client
        └── bin
            └── main.rs

I could make one executable which manages both concerns, but that's not what I want to do, unless it's very good practice.

Answer 1

You can specify multiple binaries using [[bin]] , as mentioned here :

[[bin]]
name = "daemon"
path = "src/daemon/bin/main.rs"

[[bin]]
name = "client"
path = "src/client/bin/main.rs"

Tip: If you instead put these files in src/bin/daemon.rs and src/bin/client.rs , you'll get two executables named daemon and client as Cargo compiles all files in src/bin into executables with the same name automatically. You need to specify names and paths like in the snippet above only if you don't follow this convention.

Answer 2

Another way is to use the workspace feature . This will provide more flexibility due to the fact that we can have more than one library. Example project structure:

.
├── Cargo.toml
├── cli
│   ├── Cargo.toml
│   └── src
│       └── main.rs
├── core
│   ├── Cargo.toml
│   └── src
│       └── lib.rs
├── daemon
│   ├── Cargo.toml
│   └── src
│       └── main.rs
├── gui
│   ├── Cargo.toml
│   └── src
│       └── main.rs
└── rpc
    ├── Cargo.toml
    └── src
        └── lib.rs

Contents of the root Cargo.toml :

[workspace]
members = ["cli", "core", "daemon", "gui", "rpc"]

Answer 3

Another format could be to replicate what the Crates.io source code has done, if you have a massive project, something like:

Main Library in src, with a Bin folder with your executables. Then make calls to your main library crate from your executables.

That way you library is centralized so easier to find things as it's cached.