kvbm_logical/pubsub.rs
1// SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
2// SPDX-License-Identifier: Apache-2.0
3
4//! Publisher trait for distributed messaging.
5//!
6//! This module provides the `Publisher` trait used by the event pipeline.
7//! Concrete implementations (NATS, Stub) remain in `dynamo-kvbm`.
8
9use anyhow::Result;
10use bytes::Bytes;
11use futures::future::BoxFuture;
12
13/// Publisher trait for sending messages to subjects.
14///
15/// Publishers are responsible for sending messages to named subjects.
16/// Messages are delivered to all subscribers matching the subject pattern.
17pub trait Publisher: Send + Sync {
18 /// Publish a message to a subject.
19 ///
20 /// This queues the message for delivery and returns immediately.
21 /// Use [`flush`](Publisher::flush) to ensure delivery.
22 fn publish(&self, subject: &str, payload: Bytes) -> Result<()>;
23
24 /// Flush pending messages to ensure delivery.
25 ///
26 /// Returns when all previously published messages have been acknowledged
27 /// by the messaging system.
28 fn flush(&self) -> BoxFuture<'static, Result<()>>;
29}