# Work Summary: Critical Fixes for Timer-Driven Execution Pipeline
**Date:** 2026-01-16  
**Status:** COMPLETED ✅

---

## Overview

Fixed two P0 blocking issues that prevented the timer-driven automation pipeline from completing end-to-end:
1. **Message Loop Bug** - Execution manager processing completion messages infinitely
2. **Worker Runtime Resolution** - Worker unable to find correct runtime for actions

Both issues are now resolved, and executions complete successfully with the correct runtime.

---

## Issue 1: Message Loop in Execution Manager

### Problem
Execution manager entered an infinite loop where `ExecutionCompleted` messages were routed back to the status queue and reprocessed indefinitely.

**Symptoms:**
```
INFO Processing status change for execution 137: Failed
INFO Updated execution 137 status: Failed -> Failed
INFO Handling completion for execution: 137
INFO Published execution.completed notification for execution: 137
[repeats infinitely]
```

### Root Cause
The execution manager's queue was bound with wildcard pattern `execution.status.#` which matched:
- `execution.status.changed` ✅ (intended)
- `execution.completed` ❌ (unintended - caused loop)

When an execution completed, the manager published an `ExecutionCompleted` message with routing key `execution.completed`. This message was routed back to the same queue due to the wildcard pattern, causing infinite reprocessing.

### Solution
Changed queue binding in `common/src/mq/connection.rs` from wildcard to exact match:
```rust
// Before
self.bind_queue(
    &config.rabbitmq.queues.execution_status.name,
    &config.rabbitmq.exchanges.executions.name,
    "execution.status.#",  // Matches ALL execution.status.* messages
)

// After
self.bind_queue(
    &config.rabbitmq.queues.execution_status.name,
    &config.rabbitmq.exchanges.executions.name,
    "execution.status.changed",  // Only matches status change messages
)
```

### Files Modified
- `crates/common/src/mq/connection.rs` - Line 407

### Result
✅ ExecutionCompleted messages no longer route to status queue  
✅ Manager processes each status change exactly once  
✅ No more infinite loops

---

## Issue 2: Worker Runtime Resolution Failure

### Problem
Worker received execution messages but failed with:
```
ERROR Runtime not found: No runtime found for action: core.echo
```

Even though:
- Worker had shell runtime available ✅
- Action `core.echo` requires shell runtime ✅
- Runtime matching logic existed ✅

### Root Cause
The worker's runtime selection relied on `can_execute()` methods that checked file extensions and action_ref patterns:
- Python runtime checked for `.py` in action_ref
- Shell runtime checked for specific patterns
- `core.echo` didn't match any patterns

The action's runtime metadata (stored in database as `runtime: 3` → shell runtime) was being ignored.

### Solution Architecture

**1. Added `runtime_name` field to `ExecutionContext`**
```rust
pub struct ExecutionContext {
    // ... existing fields
    pub runtime_name: Option<String>,  // NEW: "python", "shell", etc.
}
```

**2. Updated worker executor to load runtime from database**
```rust
// Load runtime information if specified
let runtime_name = if let Some(runtime_id) = action.runtime {
    match sqlx::query_as::<_, RuntimeModel>("SELECT * FROM attune.runtime WHERE id = $1")
        .bind(runtime_id)
        .fetch_optional(&self.pool)
        .await
    {
        Ok(Some(runtime)) => {
            debug!("Loaded runtime '{}' for action '{}'", runtime.name, action.r#ref);
            Some(runtime.name)
        }
        // ... error handling
    }
} else {
    None
};
```

**3. Updated `RuntimeRegistry::get_runtime()` to prefer runtime_name**
```rust
pub fn get_runtime(&self, context: &ExecutionContext) -> RuntimeResult<&dyn Runtime> {
    // If runtime_name is specified, use it directly (no guessing!)
    if let Some(ref runtime_name) = context.runtime_name {
        return self
            .runtimes
            .iter()
            .find(|r| r.name() == runtime_name)
            .map(|r| r.as_ref())
            .ok_or_else(|| {
                RuntimeError::RuntimeNotFound(format!(
                    "Runtime '{}' not found (available: {})",
                    runtime_name,
                    self.list_runtimes().join(", ")
                ))
            });
    }

    // Fall back to can_execute() for ad-hoc executions
    self.runtimes
        .iter()
        .find(|r| r.can_execute(context))
        .map(|r| r.as_ref())
        .ok_or_else(|| RuntimeError::RuntimeNotFound(...))
}
```

**4. Updated worker to register individual runtimes**
```rust
// Register individual runtimes so they can be matched by name
runtime_registry.register(Box::new(PythonRuntime::new()));
runtime_registry.register(Box::new(ShellRuntime::new()));

// Also keep local runtime as fallback
runtime_registry.register(Box::new(LocalRuntime::new()));
```

### Files Modified
- `crates/worker/src/runtime/mod.rs` - Added runtime_name field, updated get_runtime()
- `crates/worker/src/executor.rs` - Load runtime from database, populate runtime_name
- `crates/worker/src/service.rs` - Register individual Python/Shell runtimes
- Test files updated to include new field:
  - `crates/worker/src/runtime/python.rs`
  - `crates/worker/src/runtime/shell.rs`
  - `crates/worker/src/runtime/local.rs`

### Result
✅ Worker correctly identifies runtime from database metadata  
✅ Runtime selection based on authoritative data, not pattern matching  
✅ Backward compatible with can_execute() for ad-hoc executions  
✅ Actions execute successfully with correct runtime

---

## Verification

### Test Execution (Execution ID 180)
```
2026-01-16T04:01:08.319898Z  INFO Starting execution: 180
2026-01-16T04:01:08.326189Z  INFO Executing shell action: core.echo (execution_id: 180)
2026-01-16T04:01:08.328574Z  INFO Execution 180 succeeded
2026-01-16T04:01:08.330727Z  INFO Execution 180 completed successfully in 2ms
```

### Database State
```sql
SELECT id, status FROM attune.execution WHERE id >= 177;
 id  |  status
-----+-----------
 182 | completed
 181 | completed
 180 | completed
 179 | completed
 178 | completed
```

### Runtime Registration
```
2026-01-16T04:00:46.998849Z  INFO Registered runtimes: ["python", "shell", "local"]
```

---

## Architecture Improvements

### Before
```
Action (core.echo)
  └─> Worker receives execution
      └─> RuntimeRegistry.get_runtime()
          └─> Check can_execute() on each runtime
              └─> PythonRuntime.can_execute() → ❌ (no .py)
              └─> ShellRuntime.can_execute() → ❌ (no pattern match)
              └─> ERROR: Runtime not found
```

### After
```
Action (core.echo, runtime_id: 3)
  └─> Worker loads action from database
      └─> Query runtime table: runtime_id=3 → name="shell"
      └─> ExecutionContext { runtime_name: Some("shell"), ... }
      └─> RuntimeRegistry.get_runtime()
          └─> Direct name match: "shell" → ShellRuntime ✅
          └─> SUCCESS: Execute with shell runtime
```

---

## Impact

### Immediate Benefits
1. **End-to-end timer pipeline works** - Events trigger actions successfully
2. **Reliable runtime selection** - Based on database metadata, not heuristics
3. **No more infinite loops** - Execution manager processes messages correctly
4. **Fast execution** - Shell actions complete in ~2-3ms

### System Status
- ✅ Sensor: Firing timer events every 10 seconds
- ✅ Executor: Processing enforcements, scheduling executions
- ✅ Worker: Executing actions with correct runtime
- ✅ End-to-end: Timer → Event → Rule → Enforcement → Execution → Completion

---

## Known Issues

### Message Re-delivery
Executions are being processed multiple times due to message acknowledgment issues. This is a separate concern from the fixed issues and does not prevent successful execution.

**Example:**
```
Processing execution.scheduled for execution: 180
Starting execution: 180
Execution 180 completed successfully
Processing execution.scheduled for execution: 180  # Re-delivered
Starting execution: 180
Execution 180 completed successfully
```

**Impact:** Minor - Executions still complete successfully, just with redundant processing.

**Next Steps:** Investigate message acknowledgment in worker consumer to ensure proper ACK/NACK handling.

---

## Testing Recommendations

### Manual Testing
```bash
# 1. Start all services
./target/debug/attune-sensor -c config.development.yaml &
./target/debug/attune-executor -c config.development.yaml &
./target/debug/attune-worker -c config.development.yaml &

# 2. Monitor logs
tail -f /tmp/sensor.log | grep "Timer.*fired"
tail -f /tmp/executor.log | grep "Execution.*scheduled"
tail -f /tmp/worker.log | grep "completed successfully"

# 3. Check database
psql -U postgres -h localhost -d attune \
  -c "SELECT id, status, action_ref FROM attune.execution ORDER BY id DESC LIMIT 10;"
```

### Integration Tests
- Test timer events trigger executions
- Test Python actions (verify python runtime)
- Test shell actions (verify shell runtime)
- Test execution lifecycle transitions
- Test message routing (no loops, no duplicate processing)

---

## Configuration Note

Added message queue configuration to `config.development.yaml`:
```yaml
message_queue:
  url: amqp://guest:guest@localhost:5672
```

This was missing and caused sensor/executor/worker to fail on startup in development environment.

---

## Summary

Both P0 blocking issues are **RESOLVED**:
1. ✅ Message loop fixed via queue binding change
2. ✅ Runtime resolution fixed via database-driven selection

The timer-driven automation pipeline now works end-to-end:
```
Timer (10s) → Event → Rule Match → Enforcement → Execution → Worker (shell) → Completion (2-3ms)
```

**Next Priority:** Address message re-delivery issue to eliminate redundant processing.