New approach to dependency injection for 1.x

src/lib.rs

@@ -1,125 +1,35 @@
+#![deny(missing_docs)]
 //! # aerosol
 //! Simple dependency injection for Rust
 //!
-//! The two main exports of this crate are the `define_context`
-//! and `define_interface` macros.
+//! Optional features: `async`
 //!
-//! Contexts are containers for multiple dependencies, allowing
-//! them to be passed around as one with relative ease. Interfaces
-//! are specialized traits which place constraints on contexts,
-//! indicating exactly what dependencies a context must provide.
+//! ## `async`
 //!
-//! Contexts are typically created at the top level of an application,
-//! as they specify exactly what concrete versions of all dependencies
-//! are going to be used. A single context is created with a precise
-//! set of depenencies, and is then threaded through the rest of the
-//! application as a generic parameter.
+//! Allows resources to be constructed asynchrously, and provies a corresponding
+//! `AsyncConstructibleResource` trait.
 //!
-//! Interfaces are used at every level of an application, as they
-//! allow each piece of code to independently specify what dependencies
-//! are required. Interfaces can "inherit" the dependencies of other
-//! interfaces, with the idea being that this inheritance will form
-//! a tree, such that there will be some "root interface" which contains
-//! the union of all dependencies required by the whole application.
+//! ## `axum`
 //!
-//! This pattern allows dependencies to be added or removed from any
-//! part of the application without having to modify the code at every
-//! level, to thread or un-thread the new or old dependencies through.
-//!
-//! ## Example
-//!
-//! ```
-//! #![recursion_limit="128"]
-//! use std::sync::Arc;
-//! use std::fmt::Debug;
-//!
-//! // We will depend on some kind of logger
-//! trait Logger: Debug {
-//!     fn log(&self, msg: &str);
-//! }
-//!
-//! // We have a specific implementation of a stdout logger
-//! #[derive(Debug)]
-//! struct StdoutLogger;
-//!
-//! impl Logger for StdoutLogger {
-//!     fn log(&self, msg: &str) {
-//!         println!("{}", msg);
-//!     }
-//! }
-//!
-//! struct StdoutLoggerFactory;
-//! impl aerosol::Factory for StdoutLoggerFactory {
-//!     type Object = Arc<Logger>;
-//!     fn build(_: ()) -> Result<Arc<Logger>, anyhow::Error> {
-//!         Ok(Arc::new(StdoutLogger))
-//!     }
-//! }
-//!
-//! // Part of our application does some work
-//! aerosol::define_interface!(
-//!     WorkerInterface {
-//!         fn logger(&self) -> Arc<Logger>;
-//!     }
-//! );
-//!
-//! fn do_work<I: WorkerInterface>(iface: I) {
-//!     iface.logger().log("Doing some work!");
-//! }
-//!
-//! // Our application does multiple pieces of work
-//! aerosol::define_interface!(
-//!     AppInterface: WorkerInterface + Clone {}
-//! );
-//!
-//! fn run_app<I: AppInterface>(iface: I, num_work_items: usize) {
-//!     for _ in 0..num_work_items {
-//!         do_work(iface.clone());
-//!     }
-//! }
-//!
-//! // At the very top level, we specify the implementations
-//! // of our dependencies.
-//! aerosol::define_context!(
-//!     AppContext {
-//!         logger: Arc<Logger> [StdoutLoggerFactory],
-//!     }
-//! );
-//!
-//! let context = AppContext::new().unwrap();
-//!
-//! run_app(context, 4);
-//! ```
-//!
-//! See the individual macro documentation for more details.
+//! Provies integrations with the `axum` web framework. See the `axum` module
+//! for more information.
 
-#[doc(hidden)]
-pub extern crate tt_call;
+#[cfg(feature = "async")]
+mod async_;
+#[cfg(feature = "async")]
+mod async_constructible;
+#[cfg(feature = "axum")]
+pub mod axum;
+mod resource;
+mod slot;
+mod state;
+mod sync;
+mod sync_constructible;
 
-mod context;
-mod interface;
-mod join;
-mod parse;
+pub use resource::Resource;
+pub use state::Aerosol;
 
-/// The building block for this crate. Automatically implemented
-/// for contexts providing a dependency of type `T`.
-///
-/// Super-trait of all interfaces requiring a dependency of type
-/// `T`.
-pub trait Provide<T> {
-    fn provide(&self) -> T;
-}
+pub use sync_constructible::ConstructibleResource;
 
-/// Implement this trait to provide a convenient syntax for
-/// constructing implementations of dependencies.
-pub trait Factory<Args = ()> {
-    type Object;
-    fn build(args: Args) -> Result<Self::Object, anyhow::Error>;
-}
-
-/// Allows cloning a context whilst replacing one dependency
-/// with a different implementation. Must be explicitly listed
-/// as a super-trait of an interface to use.
-pub trait ProvideWith<T>: Provide<T> + Sized {
-    fn provide_with<E, F: FnOnce(T) -> Result<T, E>>(&self, f: F) -> Result<Self, E>;
-}
+#[cfg(feature = "async")]
+pub use async_constructible::AsyncConstructibleResource;