Struct AppState 

pub struct AppState { /* private fields */ }

Application state container.

AppState holds typed state values that can be shared across request handlers. State is typically set up when creating the application and injected into requests by the router/server.

Example

use fastapi_core::extract::{AppState, State};
use std::sync::Arc;

// Define your state types
struct DatabasePool { /* ... */ }
struct Config { api_key: String }

// Build the app state
let state = AppState::new()
    .with(Arc::new(DatabasePool::new()))
    .with(Arc::new(Config { api_key: "secret".into() }));

// In handlers, extract the state
async fn handler(db: State<Arc<DatabasePool>>, config: State<Arc<Config>>) {
    // Use db and config...
}

Implementations

impl AppState

pub fn new() -> Self

Create an empty application state container.

pub fn with<T: Send + Sync + 'static>(self, value: T) -> Self

Add a typed state value.

The value must be Send + Sync + 'static to be safely shared across requests and threads.

pub fn get<T: Send + Sync + 'static>(&self) -> Option<&T>

Get a reference to a typed state value.

pub fn contains<T: Send + Sync + 'static>(&self) -> bool

Check if state contains a value of type T.

pub fn len(&self) -> usize

Return the number of state values.

pub fn is_empty(&self) -> bool

Returns true if no state values are stored.

Trait Implementations

impl Clone for AppState

fn clone(&self) -> AppState

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for AppState

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for AppState

fn default() -> AppState

Returns the “default value” for a type.