Struct Config 

pub struct Config<C = ()>
where
    C: DeserializeOwned + Send + Sync + 'static,
{ /* private fields */ }

Typed, layered configuration container.

C is the caller’s serde::Deserialize struct describing the configuration shape. It defaults to () so downstream code that holds an Arc<Config> (notably rtb_app::app::App) does not need to carry the type parameter explicitly.

See ConfigBuilder for the layered construction API and Config::reload for the atomic-swap reload flow.

Implementations

impl<C> Config<C>

where C: DeserializeOwned + Send + Sync + 'static,

pub fn builder() -> ConfigBuilder<C>

Start a new builder for layered construction.

pub fn with_value(value: C) -> Self

Construct a Config holding value directly, with no figment sources behind it.

Primarily useful in tests and for the rtb_test_support::TestAppBuilder::config_value shortcut — production tools should reach for Self::builder so layered defaults / user files / env vars all participate.

Calling Self::reload on the result re-parses the empty source set, which (for C: Default-shaped types) overwrites the stored value with C::default() and (for everything else) returns a parse error. Tests that need stable values across a reload should use Self::builder with an embedded_default.

pub fn get(&self) -> Arc<C>

Snapshot the currently-stored value. Cheap — no parse.

Calls that hold the returned Arc<C> across a Self::reload see the pre-reload value; the next get() observes the post-reload value. There is no tearing.

pub fn reload(&self) -> Result<(), ConfigError>

Re-read every registered source and atomically swap the stored value.

Errors leave the stored value untouched.

pub fn subscribe(&self) -> Receiver<Arc<C>>

Subscribe to configuration changes.

The returned watch::Receiver sees the current value immediately via watch::Receiver::borrow; each successful Self::reload wakes .changed().await. Failed reloads don’t wake subscribers — callers only ever observe values that are also stored in Self::get.

Trait Implementations

impl<C> Clone for Config<C>

where C: DeserializeOwned + Send + Sync + 'static,

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<C> Debug for Config<C>

where C: DeserializeOwned + Send + Sync + 'static,

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

Formats the value using the given formatter.

impl<C> Default for Config<C>

where C: DeserializeOwned + Default + Send + Sync + 'static,

fn default() -> Self

Returns the “default value” for a type.