The CLI

The ruststream command-line tool drives cargo with the framework's subcommands. Scaffolding a new project is cargo generate (see Scaffolding below), so the tool no longer ships its own new command.

cargo install ruststream --features cli

A RustStream service is an ordinary Rust binary whose main is generated by #[ruststream::app]. The CLI does not introspect it; run and asyncapi gen shell out to cargo run against the target crate.

Commands

ruststream run                         # cargo run -- run, against ./Cargo.toml
ruststream run -p ./my-service         # against another crate
ruststream run --release               # release build
ruststream asyncapi gen                # print the AsyncAPI document
ruststream asyncapi gen -o spec.json   # write it to a file
ruststream asyncapi gen --yaml         # YAML instead of JSON

run and asyncapi gen take -p/--manifest-path (defaulting to the current directory) to point at a crate other than the working directory.

The generated entry point

#[ruststream::app] turns a builder function into a main that understands run and asyncapi gen, so there is no runtime boilerplate:

examples/quickstart.rs

use ruststream::memory::MemoryBroker;
use ruststream::runtime::{AppInfo, RustStream};

#[ruststream::app]
fn app() -> RustStream {
    RustStream::new(AppInfo::new("orders", "0.1.0"))
        .with_broker(MemoryBroker::new(), |b| b.include(handle))
}

Because the dispatch lives in the generated binary, both ruststream run and a plain cargo run -- run start the service the same way. ruststream run is a convenience that finds the crate and forwards the command to cargo.

Scaffolding

New projects are generated with cargo generate from a template, not by this tool; the command and the project it writes are in the quick start. Templates are owned by the crate whose broker they wire: the in-memory starter lives in this repo, and each broker repo ships its own, typically one per transport or topology (for example nats vs nats-js). Authoring a template for a new broker follows the template contract.