Event Bus & Envelopes

Architectural Layer: L0/L8 Event Bus
Source Directory: src/events
File Count: 4 source files

Broadcast channels, structured telemetry envelopes, and asynchronous event distribution.

Module Files & Detailed Reference

Source File	Lines	Key Types	Responsibility
bus.rs	326	BroadcastEventBus, EventFilter	EventBus trait and BroadcastEventBus implementation (D-10, D-11, D-12,...
envelope.rs	259	EventEnvelope, EventCategory	Event envelope with metadata, causal tracking, and categorization (D-1...
mod.rs	11	Functions/Traits	Events module - typed event contracts and sequencing (KRN-03) Per D-1...
types.rs	1501	TaskSummary, EventType	Typed event vocabulary covering all domain concepts (KRN-03)

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src/events/bus.rs

• Source Link: src/events/bus.rs on GitHub
• Lines of Code: 326 (10080 bytes)

Primary Responsibility

EventBus trait and BroadcastEventBus implementation (D-10, D-11, D-12, EVT-01, EVT-03).

Types & Trait Declarations

• Structs (2): BroadcastEventBus, EventFilter
• Traits (1): EventBus

Key Functions & Signatures (15 shown)

// pub
fn all() -> Self;
// pub
fn with_mission(mut self, mission_id: MissionId) -> Self;
// pub
fn with_session(mut self, session_id: SessionId) -> Self;
// pub
fn with_type(mut self, event_type: impl Into<String>) -> Self;
// pub
fn with_category(mut self, category: EventCategory) -> Self;
// pub
fn from_seq(mut self, sequence: u64) -> Self;
// pub
fn to_seq(mut self, sequence: u64) -> Self;
// pub
fn matches(&self, envelope: &EventEnvelope) -> bool;
// private
async fn publish(&self, envelope: EventEnvelope) -> Result<(), M31AError>;
// private
async fn subscribe(&self, filter: EventFilter) -> EventReceiver;
// pub
fn new(capacity: usize) -> Self;
// pub
fn capacity(&self) -> usize;
// pub
fn subscriber_count(&self) -> usize;
// private
fn default() -> Self;
// private
async fn publish(&self, envelope: EventEnvelope) -> Result<(), M31AError>;

Unit Verification (4 inline tests)

Tests defined within module: test_event_filter_builder_and_matching, test_broadcast_event_bus_publish_no_subscribers, test_broadcast_event_bus_delivery_and_filtering, test_broadcast_event_bus_lag_detection

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src/events/envelope.rs

• Source Link: src/events/envelope.rs on GitHub
• Lines of Code: 259 (8479 bytes)

Primary Responsibility

Event envelope with metadata, causal tracking, and categorization (D-13, EVT-01, EVT-02).

Types & Trait Declarations

• Structs (1): EventEnvelope
• Enums (1): EventCategory

Key Functions & Signatures (11 shown)

// private
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result;
// private
fn from_str(s: &str) -> Result<Self, Self::Err>;
// pub
fn new(sequence: u64,
        mission_id: Option<MissionId>,
        session_id: Option<SessionId>,
        actor: Strin;
// pub
fn new_for_run(sequence: u64,
        run_id: Option<ExecutionRunId>,
        session_id: Option<SessionId>,
        act;
// pub
fn with_schema_version(sequence: u64,
        mission_id: Option<MissionId>,
        session_id: Option<SessionId>,
    ;
// pub
fn with_causation(mut self,
        correlation_id: Option<String>,
        causation_id: Option<EventId>,) -> Self;
// pub
fn with_category(mut self, category: EventCategory) -> Self;
// private
fn test_event_envelope_new();
// private
fn test_event_envelope_causation_and_category();
// private
fn test_event_envelope_serde_roundtrip();
// private
fn test_event_envelope_generates_unique_ids();

Unit Verification (4 inline tests)

Tests defined within module: test_event_envelope_new, test_event_envelope_causation_and_category, test_event_envelope_serde_roundtrip, test_event_envelope_generates_unique_ids

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src/events/mod.rs

• Source Link: src/events/mod.rs on GitHub
• Lines of Code: 11 (337 bytes)

Primary Responsibility

Events module - typed event contracts and sequencing (KRN-03) Per D-16, events/ owns typed event contracts and event sequencing.

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src/events/types.rs

• Source Link: src/events/types.rs on GitHub
• Lines of Code: 1501 (53182 bytes)
• Runtime Properties: 🛡️ Enforces Policy Gate

Primary Responsibility

Typed event vocabulary covering all domain concepts (KRN-03)

Types & Trait Declarations

• Structs (1): TaskSummary
• Enums (1): EventType

Key Functions & Signatures (8 shown)

// pub
fn name(&self) -> &'static str;
// private
fn test_event_type_variants_count();
// private
fn test_event_type_serde_roundtrip();
// private
fn test_event_type_name();
// private
fn test_all_domains_covered();
// private
fn test_controller_lifecycle_events_serde_roundtrip();
// private
fn test_scheduler_events_serde_roundtrip();
// private
fn test_engineering_memory_events_serde_roundtrip();

Unit Verification (7 inline tests)

Tests defined within module: test_event_type_variants_count, test_event_type_serde_roundtrip, test_event_type_name, test_all_domains_covered, test_controller_lifecycle_events_serde_roundtrip, test_scheduler_events_serde_roundtrip, test_engineering_memory_events_serde_roundtrip

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