awsim_core/
events.rs

1use serde::{Deserialize, Serialize};
2use tokio::sync::broadcast;
3
4/// An internal event emitted by a service to signal something happened.
5///
6/// Consumers (e.g. the background event router in `awsim`) subscribe to the
7/// bus and perform cross-service fan-out (e.g. SNS → SQS delivery).
8#[derive(Debug, Clone, Serialize, Deserialize)]
9pub struct InternalEvent {
10    /// Originating service: "s3", "sns", "eventbridge", etc.
11    pub source: String,
12    /// Fine-grained event type: "s3:ObjectCreated:Put", "sns:Publish", etc.
13    pub event_type: String,
14    /// AWS region the event occurred in.
15    pub region: String,
16    /// AWS account ID the event occurred in.
17    pub account_id: String,
18    /// Event-specific payload (free-form JSON).
19    pub detail: serde_json::Value,
20}
21
22/// A cheap-to-clone handle to the shared broadcast channel used as an
23/// internal event bus between services.
24#[derive(Clone, Debug)]
25pub struct EventBus {
26    sender: broadcast::Sender<InternalEvent>,
27}
28
29impl EventBus {
30    /// Create a new event bus with a buffer of 1 024 events.
31    pub fn new() -> Self {
32        let (sender, _) = broadcast::channel(1024);
33        Self { sender }
34    }
35
36    /// Publish an event to all current subscribers.
37    ///
38    /// Silently drops the event if there are no active subscribers (the
39    /// broadcast channel returns `SendError` in that case, which we ignore).
40    pub fn publish(&self, event: InternalEvent) {
41        let _ = self.sender.send(event);
42    }
43
44    /// Subscribe to the event stream.  Each call returns an independent
45    /// receiver that starts from the next event published after the call.
46    pub fn subscribe(&self) -> broadcast::Receiver<InternalEvent> {
47        self.sender.subscribe()
48    }
49}
50
51impl Default for EventBus {
52    fn default() -> Self {
53        Self::new()
54    }
55}
awsim_core/events.rs

awsim_core/
events.rs
