Using rocket api a library for another application

[sahilarora3117]

I want to create an application written in GTK rust and an API that is written in rocket. Can i somehow bundle the API with the GTK application, so that the server can be starter before the application and then the UI uses it (network calls on localhost)

[robertwayne]

There are a variety of ways to accomplish this, but one way is to just pass an instance of Rocket off to Tokio via tokio::spawn. You would need to be using a custom runtime (or a default Tokio runtime), as opposed to using the Rocket-provided macros (#[rocket::main] or #[launch]).

An example could be:

#[tokio::main]
async fn main() {
    tokio::spawn(rocket::build().mount("/", routes![index]).launch());

    loop {
        // ... your main app loop
    }
}

There are some considerations you must make of course: you lose out on some things provided by Rocket by using a custom runtime (such as graceful shutdown handling). See: https://api.rocket.rs/v0.5-rc/rocket/config/struct.Shutdown.html#example

This comes with another caveat that you'd need to bundle (or embed) your Rocket.toml file with your binary (or manually define your Config). See: https://api.rocket.rs/v0.5-rc/rocket/config/struct.Config.html#method.figment

[blackghost1987]

There's also the new rocket::execute function (released in rc.2), which makes it possible to start a Rocket instance inside another application, without constructing a custom Tokio runtime.

For usage examples, see:
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