Struct DataLoader 

pub struct DataLoader<S: DataSource = TradingViewSource> { /* private fields */ }

Event-driven data loader — connects a source to multiple sinks.

Architecture:

Source task → source_tx ──→ [fan-out task] ──→ sink_tx_0 → sink task 0
                                       ├───────→ sink_tx_1 → sink task 1
                                       └───────→ sink_tx_N → sink task N

The source produces Vec<MarketEvent> batches and sends them via a single mpsc channel. A fan-out task reads from that channel and clones each batch to every sink’s individual channel. Each sink has its own task that reads from its channel and calls sink.accept().

Implementations

impl<S: DataSource> DataLoader<S>

pub fn builder() -> DataLoaderBuilder<S>

Create a new builder with default configuration.

pub async fn start(&mut self) -> Result<()>

Start the loader: spawns source, fan-out, and per-sink tasks.

This method consumes the source and sink channels; calling it twice returns an error.

pub async fn shutdown(&mut self) -> Result<()>

Initiate graceful shutdown.

Cancels all spawned tasks and waits for them to finish.

pub fn cancel_token(&self) -> CancellationToken

Returns a clone of the cancellation token for external monitoring.