dynamo_runtime/component/
component.rs

1// SPDX-FileCopyrightText: Copyright (c) 2024-2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
2// SPDX-License-Identifier: Apache-2.0
3//
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at
7//
8// http://www.apache.org/licenses/LICENSE-2.0
9//
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16use anyhow::Context;
17use async_trait::async_trait;
18use futures::stream::StreamExt;
19use futures::{Stream, TryStreamExt};
20
21use super::*;
22
23use crate::traits::events::{EventPublisher, EventSubscriber};
24
25#[async_trait]
26impl EventPublisher for Component {
27    fn subject(&self) -> String {
28        format!("namespace.{}.component.{}", self.namespace.name, self.name)
29    }
30
31    async fn publish(
32        &self,
33        event_name: impl AsRef<str> + Send + Sync,
34        event: &(impl Serialize + Send + Sync),
35    ) -> Result<()> {
36        let bytes = serde_json::to_vec(event)?;
37        self.publish_bytes(event_name, bytes).await
38    }
39
40    async fn publish_bytes(
41        &self,
42        event_name: impl AsRef<str> + Send + Sync,
43        bytes: Vec<u8>,
44    ) -> Result<()> {
45        let subject = format!("{}.{}", self.subject(), event_name.as_ref());
46        Ok(self
47            .drt()
48            .nats_client()
49            .client()
50            .publish(subject, bytes.into())
51            .await?)
52    }
53}
54
55#[async_trait]
56impl EventSubscriber for Component {
57    async fn subscribe(
58        &self,
59        event_name: impl AsRef<str> + Send + Sync,
60    ) -> Result<async_nats::Subscriber> {
61        let subject = format!("{}.{}", self.subject(), event_name.as_ref());
62        Ok(self.drt().nats_client().client().subscribe(subject).await?)
63    }
64
65    async fn subscribe_with_type<T: for<'de> Deserialize<'de> + Send + 'static>(
66        &self,
67        event_name: impl AsRef<str> + Send + Sync,
68    ) -> Result<impl Stream<Item = Result<T>> + Send> {
69        let subscriber = self.subscribe(event_name).await?;
70
71        // Transform the subscriber into a stream of deserialized events
72        let stream = subscriber.map(move |msg| {
73            serde_json::from_slice::<T>(&msg.payload)
74                .with_context(|| format!("Failed to deserialize event payload: {:?}", msg.payload))
75        });
76
77        Ok(stream)
78    }
79}
80
81#[cfg(feature = "integration")]
82#[cfg(test)]
83mod tests {
84    use super::*;
85
86    // todo - make a distributed runtime fixture
87    // todo - two options - fully mocked or integration test
88    #[tokio::test]
89    async fn test_publish_and_subscribe() {
90        let rt = Runtime::from_current().unwrap();
91        let dtr = DistributedRuntime::from_settings(rt.clone()).await.unwrap();
92        let ns = dtr.namespace("test_component".to_string()).unwrap();
93        let cp = ns.component("test_component".to_string()).unwrap();
94
95        // Create a subscriber on the component
96        let mut subscriber = cp.subscribe("test_event").await.unwrap();
97
98        // Publish a message from the component
99        cp.publish("test_event", &"test_message".to_string())
100            .await
101            .unwrap();
102
103        // Receive the message
104        if let Some(msg) = subscriber.next().await {
105            let received = String::from_utf8(msg.payload.to_vec()).unwrap();
106            assert_eq!(received, "\"test_message\"");
107        }
108
109        rt.shutdown();
110    }
111}
dynamo_runtime/component/component.rs

dynamo_runtime/component/
component.rs
