# Zastava Runtime Observer (CRI Container Lifecycle Tracking)

## Module
Zastava

## Status
IMPLEMENTED

## Description
Full CRI-based container runtime observer with lifecycle tracking, state tracking, and polling. Supports both CRI (Linux) and Docker Windows runtimes.

## Implementation Details
- **Observer Program**: `src/Zastava/StellaOps.Zastava.Observer/Program.cs` -- CRI-based observer entry point
- **CRI runtime**: `src/Zastava/StellaOps.Zastava.Observer/ContainerRuntime/Cri/` -- `CriRuntimeClient.cs`, `CriRuntimeClientFactory.cs`, `CriModels.cs`, `CriConversions.cs` for CRI socket-based container monitoring
- **ContainerStateTracker**: `src/Zastava/StellaOps.Zastava.Observer/ContainerRuntime/ContainerStateTracker.cs` -- tracks container lifecycle state transitions
- **ContainerLifecycleHostedService**: `src/Zastava/StellaOps.Zastava.Observer/Worker/ContainerLifecycleHostedService.cs` -- background service for lifecycle event processing
- **ContainerRuntimePoller**: `src/Zastava/StellaOps.Zastava.Observer/Worker/ContainerRuntimePoller.cs` -- polls container runtime for state changes
- **RuntimeEventBuffer**: `src/Zastava/StellaOps.Zastava.Observer/Runtime/RuntimeEventBuffer.cs` -- buffers events before dispatch
- **RuntimeEventDispatchService**: `src/Zastava/StellaOps.Zastava.Observer/Worker/RuntimeEventDispatchService.cs` -- dispatches events to backend
- **RuntimeEventFactory**: `src/Zastava/StellaOps.Zastava.Observer/Worker/RuntimeEventFactory.cs` -- creates typed runtime events
- **ObserverBootstrapService**: `src/Zastava/StellaOps.Zastava.Observer/Worker/ObserverBootstrapService.cs` -- observer startup and initialization
- **BackoffCalculator**: `src/Zastava/StellaOps.Zastava.Observer/Worker/BackoffCalculator.cs` -- exponential backoff for retry logic
- **RuntimeFactsClient**: `src/Zastava/StellaOps.Zastava.Observer/Backend/RuntimeFactsClient.cs` -- client for posting runtime facts to backend
- **RuntimeEventsClient**: `src/Zastava/StellaOps.Zastava.Observer/Backend/RuntimeEventsClient.cs` -- client for posting runtime events
- **ZastavaObserverOptions**: `src/Zastava/StellaOps.Zastava.Observer/Configuration/ZastavaObserverOptions.cs` -- observer configuration
- **Tests**: `src/Zastava/__Tests/StellaOps.Zastava.Observer.Tests/` -- `ContainerRuntimePollerTests.cs`, `Runtime/RuntimeEventBufferTests.cs`, `Worker/RuntimeEventFactoryTests.cs`, `Backend/RuntimeEventsClientTests.cs`
- **Source**: Feature matrix scan

## E2E Test Plan
- [ ] Verify CRI runtime client connects to CRI socket and lists containers
- [ ] Test container state tracker detects start/stop/restart lifecycle events
- [ ] Verify runtime event buffer batches and dispatches events efficiently
- [ ] Test both Linux CRI and Windows Docker runtime support
- [ ] Verify observer bootstrap initializes and recovers from failures with backoff
- [ ] Test runtime facts and events are posted to backend clients