* Perfect! Let me create a summary of the changes made:
## Summary
I've successfully implemented a solution to enable deletion of tasks that have children. The implementation uses an **application-level approach** to handle the foreign key constraint issue.
### Changes Made
#### 1. **Database Model Enhancement** (crates/db/src/models/task.rs:291-321)
Added a new helper method `nullify_children_references()` that:
- Takes a list of task attempt IDs
- Finds all tasks that reference any of those attempts as their parent
- Sets their `parent_task_attempt` field to NULL
- Returns the count of affected tasks
This method uses dynamic SQL with proper parameterization to handle variable-length lists of attempt IDs.
#### 2. **API Route Enhancement** (crates/server/src/routes/tasks.rs:290-303)
Updated the `delete_task` handler to:
- Collect all attempt IDs for the task being deleted
- Call `nullify_children_references()` to break parent-child relationships before deletion
- Log the number of children that were orphaned (for debugging/monitoring)
- Proceed with normal deletion (the existing CASCADE behavior handles task_attempts)
### How It Works
1. When a user deletes a task that has children:
- The system first gathers all task_attempts for that task
- It nullifies the `parent_task_attempt` field for any child tasks
- Then proceeds with the normal deletion cascade
2. Child tasks become **independent tasks** - they remain in the system but no longer have a parent relationship
3. This approach is:
- **Non-destructive**: Child tasks are preserved
- **Safe**: Works within SQLite's constraints (no schema migration needed)
- **Transparent**: Logging shows when children are orphaned
### Testing
- ✅ Code compiles successfully (both `db` and `server` crates)
- ✅ Existing tests pass
- ✅ Type-safe implementation using sqlx
The solution resolves the foreign key constraint issue without requiring database migrations or risking data loss through cascade deletion.
* Excellent! This is the correct query for our new `nullify_children_by_attempt_id` function. Now let's create a summary of the changes:
## Summary
I've successfully revised the implementation to address the review comments. The solution now:
### Changes Made
#### 1. **Database Model Enhancement** (crates/db/src/models/task.rs:291-304)
- **Replaced** `nullify_children_references(&[Uuid])` with `nullify_children_by_attempt_id(Uuid)`
- Takes a **single attempt_id** parameter (matching the existing function naming pattern)
- Uses **sqlx macro** for type-checked queries at compile time:
```rust
sqlx::query!("UPDATE tasks SET parent_task_attempt = NULL WHERE parent_task_attempt = $1", attempt_id)
```
- No dynamic query building - fully type-safe
#### 2. **API Route Enhancement** (crates/server/src/routes/tasks.rs:290-305)
- Updated `delete_task` handler to **loop through attempts** individually
- Calls `nullify_children_by_attempt_id` for each attempt
- Tracks total number of children affected across all attempts
- Maintains logging for debugging/monitoring
#### 3. **SQLx Query Preparation**
- Generated new sqlx offline query file: `query-68bdb061b646c0401bde9cf51ff29a99019471d371b87c920d2c647ab56aea57.json`
- Added to version control for proper type-checking
### Benefits of the Revised Approach
✅ **Type-safe**: Uses sqlx macros with compile-time verification
✅ **Consistent naming**: Matches existing `find_children_by_attempt_id` pattern
✅ **Simple**: Takes single attempt_id parameter as requested
✅ **Clean code**: No dynamic query building
✅ **Well-tested**: All existing tests pass
### Verification
- ✅ Code compiles successfully (both `db` and `server` crates)
- ✅ All workspace tests pass (13 tests across all crates)
- ✅ SQLx offline queries prepared and added to git
- ✅ Ready for commit
The implementation now properly handles deletion of tasks with children using a clean, type-safe approach that follows the codebase conventions.
* Perfect! Let me create a comprehensive summary of the changes:
## Summary: Transaction-Based Task Deletion with Atomic Operations
I've successfully implemented the transaction-based approach for task deletion with full atomicity guarantees. Here's what was accomplished:
### Changes Made
#### 1. **Database Model Enhancement** (crates/db/src/models/task.rs)
**Imports** (line 3):
- Added `Executor` and `Sqlite` to support generic executor pattern
**Updated `nullify_children_by_attempt_id`** (lines 293-307):
- Changed signature to accept generic `Executor<'e, Database = Sqlite>` instead of just `&SqlitePool`
- Now works with both connection pools AND transactions
- Remains fully type-checked with sqlx macros
**Updated `delete`** (lines 309-317):
- Changed signature to accept generic `Executor<'e, Database = Sqlite>`
- Works with both pools and transactions
- Type-safe with sqlx macros
#### 2. **API Route Enhancement** (crates/server/src/routes/tasks.rs:290-319)
**Transaction Wrapper** (line 292):
```rust
let mut tx = deployment.db().pool.begin().await?;
```
**Atomic Operations** (lines 297-312):
- All `nullify_children_by_attempt_id` calls use `&mut *tx`
- Task deletion uses `&mut *tx`
- All operations happen within the same transaction
**Explicit Commit** (line 319):
```rust
tx.commit().await?;
```
- Only commits if ALL operations succeed
- Automatic rollback on any error (via Drop)
### Key Benefits
✅ **Atomicity**: Either all operations succeed or none do - no partial state
✅ **Type Safety**: All queries use sqlx macros with compile-time verification
✅ **Automatic Rollback**: If any operation fails, transaction rolls back automatically
✅ **No Orphaned State**: Children can't be detached if task deletion fails
✅ **Generic Executor Pattern**: Methods work with pools, transactions, or any SQLite executor
✅ **Zero Performance Impact**: Transaction overhead is minimal for this operation
### Transaction Flow
1. **Begin transaction** → Opens atomic context
2. **For each attempt** → Nullify child task references
3. **Delete task** → Remove parent task (CASCADE handles attempts)
4. **Commit** → Make all changes permanent
**On Error**: Transaction automatically rolls back, restoring original state
### Risk Mitigation
The transaction approach eliminates the main risk from the previous implementation:
- **Before**: If nullification succeeded but deletion failed, we'd have orphaned children with NULL parents
- **After**: Transaction ensures atomicity - either both operations complete or neither does
### Testing
- ✅ Code compiles successfully (both `db` and `server` crates)
- ✅ All workspace tests pass (13 tests)
- ✅ SQLx offline queries are properly prepared
- ✅ No breaking changes to API surface
The implementation follows the exact pattern suggested in the review and maintains full type safety while providing transactional guarantees for the deletion workflow.
* Cleanup script changes for task attempt d4746a23-472d-4e69-b58b-eeabe217a8ce
* Excellent! The change is complete. Let me provide a summary:
## Review Fix Applied: Move Logging After Transaction Commit
### Change Made (crates/server/src/routes/tasks.rs:312-319)
**Before**: Logging occurred *before* `tx.commit()`, which could log changes that would be rolled back on commit failure.
**After**: Logging moved to *after* `tx.commit()`, ensuring we only log successfully committed changes.
```rust
// Commit the transaction - if this fails, all changes are rolled back
tx.commit().await?;
// Log after successful commit
if total_children_affected > 0 {
tracing::info!(
"Nullified {} child task references before deleting task {}",
total_children_affected,
task.id
);
}
```
### Why This Matters
1. **Audit trail accuracy**: Logs should only reflect changes that actually persisted to the database
2. **Debugging clarity**: If `tx.commit()` fails, we won't have misleading log entries about successful operations
3. **Best practice**: Observability should reflect actual system state, not attempted changes
### Verification
✅ Code compiles successfully
✅ Transaction semantics preserved
✅ Logging only occurs after successful commit
The implementation now follows best practices for transactional logging - only recording events that have been durably committed to the database.
* Perfect! Removed the redundant comments. The code is now cleaner and the remaining comments provide value:
- Line 290: Explains *why* we're using a transaction (atomicity)
- Line 293-294: Explains the business logic of nullifying children
- Line 302: Explains CASCADE behavior
- Line 308: Explains rollback behavior on commit failure
All verified and compiling correctly.
baaae38cbb