dynamo_runtime/component/
namespace.rs

1// SPDX-FileCopyrightText: Copyright (c) 2024-2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
2// SPDX-License-Identifier: Apache-2.0
3
4use anyhow::Context;
5use anyhow::Result;
6use async_trait::async_trait;
7use futures::stream::StreamExt;
8use futures::{Stream, TryStreamExt};
9use serde::Deserialize;
10use serde::Serialize;
11
12use crate::component::Namespace;
13use crate::metrics::{MetricsHierarchy, MetricsRegistry};
14use crate::traits::DistributedRuntimeProvider;
15use crate::traits::events::{EventPublisher, EventSubscriber};
16
17#[async_trait]
18impl EventPublisher for Namespace {
19    fn subject(&self) -> String {
20        format!("namespace.{}", self.name)
21    }
22
23    async fn publish(
24        &self,
25        event_name: impl AsRef<str> + Send + Sync,
26        event: &(impl Serialize + Send + Sync),
27    ) -> Result<()> {
28        let bytes = serde_json::to_vec(event)?;
29        self.publish_bytes(event_name, bytes).await
30    }
31
32    async fn publish_bytes(
33        &self,
34        event_name: impl AsRef<str> + Send + Sync,
35        bytes: Vec<u8>,
36    ) -> Result<()> {
37        let subject = format!("{}.{}", self.subject(), event_name.as_ref());
38        let Some(nats_client) = self.drt().nats_client() else {
39            anyhow::bail!("KV router's Namespace EventPublisher requires NATS");
40        };
41        nats_client.client().publish(subject, bytes.into()).await?;
42        Ok(())
43    }
44}
45
46#[async_trait]
47impl EventSubscriber for Namespace {
48    async fn subscribe(
49        &self,
50        event_name: impl AsRef<str> + Send + Sync,
51    ) -> Result<async_nats::Subscriber> {
52        let subject = format!("{}.{}", self.subject(), event_name.as_ref());
53        let Some(nats_client) = self.drt().nats_client() else {
54            anyhow::bail!("KV router's Namespace EventSubscriber requires NATS");
55        };
56        Ok(nats_client.client().subscribe(subject).await?)
57    }
58
59    async fn subscribe_with_type<T: for<'de> Deserialize<'de> + Send + 'static>(
60        &self,
61        event_name: impl AsRef<str> + Send + Sync,
62    ) -> Result<impl Stream<Item = Result<T>> + Send> {
63        let subscriber = self.subscribe(event_name).await?;
64
65        // Transform the subscriber into a stream of deserialized events
66        let stream = subscriber.map(move |msg| {
67            serde_json::from_slice::<T>(&msg.payload)
68                .with_context(|| format!("Failed to deserialize event payload: {:?}", msg.payload))
69        });
70
71        Ok(stream)
72    }
73}
74
75impl MetricsHierarchy for Namespace {
76    fn basename(&self) -> String {
77        self.name.clone()
78    }
79
80    fn parent_hierarchies(&self) -> Vec<&dyn MetricsHierarchy> {
81        let mut parents = vec![];
82
83        // Walk up the namespace parent chain (grandparents to immediate parent)
84        let parent_chain: Vec<&Namespace> =
85            std::iter::successors(self.parent.as_deref(), |ns| ns.parent.as_deref()).collect();
86
87        // Add DRT first (root)
88        parents.push(&*self.runtime as &dyn MetricsHierarchy);
89
90        // Then add parent namespaces in reverse order (root -> leaf)
91        for parent_ns in parent_chain.iter().rev() {
92            parents.push(*parent_ns as &dyn MetricsHierarchy);
93        }
94
95        parents
96    }
97
98    fn get_metrics_registry(&self) -> &MetricsRegistry {
99        &self.metrics_registry
100    }
101}
102
103#[cfg(feature = "integration")]
104#[cfg(test)]
105mod tests {
106    use crate::{DistributedRuntime, Runtime};
107
108    use super::*;
109
110    // todo - make a distributed runtime fixture
111    // todo - two options - fully mocked or integration test
112    #[tokio::test]
113    async fn test_publish() {
114        let rt = Runtime::from_current().unwrap();
115        let dtr = DistributedRuntime::from_settings(rt.clone()).await.unwrap();
116        let ns = dtr.namespace("test_namespace_publish".to_string()).unwrap();
117        ns.publish("test_event", &"test".to_string()).await.unwrap();
118        rt.shutdown();
119    }
120
121    #[tokio::test]
122    async fn test_subscribe() {
123        let rt = Runtime::from_current().unwrap();
124        let dtr = DistributedRuntime::from_settings(rt.clone()).await.unwrap();
125        let ns = dtr
126            .namespace("test_namespace_subscribe".to_string())
127            .unwrap();
128
129        // Create a subscriber
130        let mut subscriber = ns.subscribe("test_event").await.unwrap();
131
132        // Publish a message
133        ns.publish("test_event", &"test_message".to_string())
134            .await
135            .unwrap();
136
137        // Receive the message
138        if let Some(msg) = subscriber.next().await {
139            let received = String::from_utf8(msg.payload.to_vec()).unwrap();
140            assert_eq!(received, "\"test_message\"");
141        }
142
143        rt.shutdown();
144    }
145}
dynamo_runtime/component/namespace.rs

dynamo_runtime/component/
namespace.rs
