pub struct HermesClient { /* private fields */ }Expand description
A high-performance client for connecting to Hermes data streams.
The HermesClient maintains multiple WebSocket connections to Hermes endpoints
for redundancy. It automatically handles connection management,
message deduplication, and provides a unified stream of price updates.
§Architecture
- Maintains multiple WebSocket connections to different endpoints
- Uses a TTL cache for deduplicating messages across connections
- Provides a single channel for consuming deduplicated messages
- Handles connection failures with exponential backoff
Implementations§
Source§impl HermesClient
impl HermesClient
Sourcepub fn new(
endpoints: Vec<Url>,
num_connections: usize,
backoff: HermesExponentialBackoff,
timeout: Duration,
channel_capacity: usize,
) -> Result<Self>
pub fn new( endpoints: Vec<Url>, num_connections: usize, backoff: HermesExponentialBackoff, timeout: Duration, channel_capacity: usize, ) -> Result<Self>
Creates a new Hermes client instance.
This is a low-level constructor. Consider using HermesClientBuilder for a more
convenient way to create clients with sensible defaults.
§Arguments
endpoints- A vector of WebSocket endpoint URLs to connect to. Must not be empty.num_connections- The number of WebSocket connections to maintain for redundancybackoff- The exponential backoff configuration for connection retriestimeout- The timeout duration for WebSocket operationschannel_capacity- The capacity of the message channel
§Returns
Returns Ok(HermesClient) on success, or an error if the configuration is invalid.
§Errors
Returns an error if:
- The
endpointsvector is empty
Sourcepub async fn start(&mut self) -> Result<Receiver<HermesServerMessage>>
pub async fn start(&mut self) -> Result<Receiver<HermesServerMessage>>
Starts the client and begins establishing WebSocket connections.
This method initializes all WebSocket connections and starts the message processing loop. It returns a receiver channel that will yield deduplicated messages from all connections.
§Returns
Returns a Receiver<HermesServerMessage> that yields deduplicated messages from all
WebSocket connections. The receiver will continue to yield messages until
all connections are closed or the client is dropped.
§Errors
This method itself doesn’t return errors, but individual connection failures are handled internally with automatic reconnection using the configured backoff strategy.
§Message Deduplication
Messages are deduplicated using a TTL cache with a 10-second window. This ensures that identical messages received from multiple connections are only delivered once.
Sourcepub async fn subscribe(
&mut self,
subscribe_request: HermesClientMessageSubscribe,
) -> Result<()>
pub async fn subscribe( &mut self, subscribe_request: HermesClientMessageSubscribe, ) -> Result<()>
Subscribes to data streams across all WebSocket connections.
This method sends the subscription request to all active WebSocket connections, ensuring redundancy. If any connection fails to subscribe, an error is returned, but other connections may still be subscribed.
§Arguments
subscribe_request- The subscription request specifying which data streams to subscribe to
§Returns
Returns Ok(()) if the subscription was successfully sent to all connections,
or an error if any connection failed to process the subscription.
Sourcepub async fn unsubscribe(
&mut self,
unsubscribe_request: HermesClientMessageUnsubscribe,
) -> Result<()>
pub async fn unsubscribe( &mut self, unsubscribe_request: HermesClientMessageUnsubscribe, ) -> Result<()>
Unsubscribes from a specific data stream across all WebSocket connections.
This method sends an unsubscribe request for the specified subscription ID to all active WebSocket connections.
§Arguments
unsubscribe_request- The unsubscribe request specifying which data streams to unsubscribe from
§Returns
Returns Ok(()) if the unsubscribe request was successfully sent to all connections,
or an error if any connection failed to process the request.