Crate qubit_spi 

Qubit SPI

Typed service provider infrastructure for Qubit Rust crates.

This crate provides the small service-provider layer that many Qubit crates need when a base crate owns a trait and extension crates provide optional implementations. A ServiceProvider supplies stable names, aliases, runtime availability, priority, and a factory method. A ProviderRegistry resolves providers by name, by automatic priority, or through an explicit fallback chain.

Examples

Register a provider and create a service by name:

use std::fmt::Debug;

use qubit_spi::{
    ProviderCreateError,
    ProviderDescriptor,
    ProviderRegistry,
    ProviderRegistryError,
    ServiceProvider,
    ServiceSpec,
};

trait Greeter: Debug + Send + Sync {
    fn greet(&self) -> &'static str;
}

#[derive(Debug)]
struct EnglishGreeter;

impl Greeter for EnglishGreeter {
    fn greet(&self) -> &'static str {
        "hello"
    }
}

#[derive(Debug)]
struct EnglishProvider;

#[derive(Debug)]
struct GreeterSpec;

impl ServiceSpec for GreeterSpec {
    type Config = ();
    type Service = dyn Greeter;
}

impl ServiceProvider<GreeterSpec> for EnglishProvider {
    fn descriptor(&self) -> Result<ProviderDescriptor, ProviderRegistryError> {
        ProviderDescriptor::new("english")?.with_aliases(&["en"])
    }

    fn create_box(&self, _config: &()) -> Result<Box<dyn Greeter>, ProviderCreateError> {
        Ok(Box::new(EnglishGreeter))
    }
}

let mut registry = ProviderRegistry::<GreeterSpec>::new();
registry
    .register(EnglishProvider)
    .expect("provider names should be unique");

let greeter = registry
    .create_box("en", &())
    .expect("registered provider should create a greeter");
assert_eq!("hello", greeter.greet());

Structs

ProviderDescriptor

Stable provider metadata used for registration and selection.

ProviderName

Stable provider id or alias accepted by a registry.

ProviderRegistry

Registry of providers for one service specification.

Enums

ProviderAvailability

Availability of a provider in the current runtime environment.

ProviderCreateError

Error returned by one provider while creating a service.

ProviderFailure

Failure recorded for one provider candidate.

ProviderRegistryError

Error returned by provider registries.

ProviderSelection

Provider candidates used by registry selection.

Traits

ServiceProvider

Factory contract for one service implementation.

ServiceSpec

Type-level description of one pluggable service family.