openraft 0.10.0-alpha.18

use crate::RaftTypeConfig;
use crate::storage::v2::apply_responder_inner::ApplyResponderInner;

/// Responder for sending client write responses after applying an entry.
///
/// This wrapper enables zero-allocation response handling by allowing state machines
/// to send responses immediately after applying each entry, rather than buffering
/// them in a Vec.
///
/// # Construction
///
/// This type cannot be constructed by user code. Instances are provided by
/// Openraft when entries are passed to [`RaftStateMachine::apply`](super::RaftStateMachine::apply).
/// State machine implementations should call [`send()`](Self::send) to
/// return the response after applying each entry.
///
/// # Example
///
/// ```ignore
/// use openraft::storage::EntryResponder;
/// use openraft::StorageError;
/// use openraft::EntryPayload;
///
/// async fn apply<I>(&mut self, entries: I) -> Result<(), StorageError<C>>
/// where
///     I: IntoIterator<Item = EntryResponder<C>>,
///     I::IntoIter: Send,
/// {
///     for (entry, responder) in entries {
///         // Compute response based on entry type
///         let response = match entry.payload {
///             EntryPayload::Blank => Response::default(),
///             EntryPayload::Normal(ref data) => {
///                 self.apply_normal_entry(data)?;
///                 self.compute_response(data)?
///             }
///             EntryPayload::Membership(ref mem) => {
///                 self.apply_membership_change(mem)?;
///                 Response::default()
///             }
///         };
///
///         // Send response only when there's a client waiting (leader entries)
///         if let Some(responder) = responder {
///             responder.send(response);
///         }
///     }
///     Ok(())
/// }
/// ```
pub struct ApplyResponder<C: RaftTypeConfig> {
    pub(crate) inner: ApplyResponderInner<C>,
}

impl<C: RaftTypeConfig> ApplyResponder<C> {
    /// Send the response after applying an entry.
    pub fn send(self, response: C::R) {
        self.inner.send(response)
    }
}