feat: add pagination to findAll() methods (P1 pre-v0.4.0)#43
Conversation
Add pagination support to TaskRepository and DependencyRepository to prevent unbounded queries before v0.4.0 adds additional tables. This prevents potential memory exhaustion in production when tables grow large. Key changes: - findAll(limit?, offset?) with default limit=100 (prevents unbounded queries) - findAllUnbounded() for explicit unbounded access (cycle detection, graph init) - count() for pagination UI support - Updated DependencyHandler to use findAllUnbounded() for graph initialization - Updated test doubles and added 7 new pagination tests - Fixed buggy test that passed objects to findAll() instead of IDs Migration notes: - Existing code calling findAll() gets paginated results (100 items max) - Callers needing all records should explicitly call findAllUnbounded() - UI can use count() for pagination display 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
PR Compliance Guide 🔍Below is a summary of compliance checks for this PR:
Compliance status legend🟢 - Fully Compliant🟡 - Partial Compliant 🔴 - Not Compliant ⚪ - Requires Further Human Verification 🏷️ - Compliance label |
||||||||||||||||||||||||
PR Code Suggestions ✨Explore these optional code suggestions:
|
|||||||||
|
Documentation: Missing JSDoc for findByStatus() pagination consideration The Suggested Fix: /**
* Find tasks by status (currently returns all matching tasks)
* NOTE: Unlike findAll(), this method is not paginated. For large datasets,
* consider using findAll() with application-level status filtering.
* TODO: Add pagination support in future version
*/
findByStatus(status: string): Promise<Result<readonly Task[]>>;Why: Developers reading this interface need to understand:
From: documentation audit | Severity: HIGH Generated by Claude Code |
|
Documentation: Missing changelog entry for pagination feature The CHANGELOG.md has an "[Unreleased]" section showing "No unreleased changes at this time." This significant feature needs to be documented before merge. Suggested Fix: Add to ## [Unreleased]
### Performance Improvements
- **Pagination for findAll() methods**: Added `limit` and `offset` parameters to `TaskRepository.findAll()` and `DependencyRepository.findAll()` with default limit of 100 records per page
- **New findAllUnbounded() methods**: Explicit unbounded retrieval for graph initialization use cases (prevents accidental full-table scans)
- **New count() methods**: Support pagination UI with total record counts without fetching all data
### Architecture
- **Explicit unbounded queries**: `DependencyHandler.create()` now uses `findAllUnbounded()` with documentation explaining why graph initialization requires all dependenciesWhy:
From: documentation audit | Severity: HIGH Generated by Claude Code |
|
Architecture: QueryHandler not updated to use pagination The Current Code ( const tasksResult = await this.repository.findAll();
// Now returns max 100 tasks due to pagination defaultThree Resolution Options: Option 1: Use findAllUnbounded() (Explicit unbounded retrieval) // ARCHITECTURE: Query handler needs complete task list for status queries
const tasksResult = await this.repository.findAllUnbounded();Pros: Clear intent, documents that full list is needed Option 2: Add pagination support to TaskStatusQuery event (Recommended) // In event interface:
interface TaskStatusQuery extends QueryEvent {
limit?: number;
offset?: number;
}
// In handler:
const tasksResult = await this.repository.findAll(query.limit, query.offset);Pros: Supports large task lists, maintains API consistency Option 3: Accept pagination limit and document in MCP tool // Document in MCP tool that findAll returns max 100 tasks
const tasksResult = await this.repository.findAll();Pros: Minimal code change Recommendation: Option 1 for now (use From: architecture audit | Severity: HIGH Generated by Claude Code |
|
Performance: Statement preparation inside findAll() method (TaskRepository) The new Current Code ( async findAll(limit?: number, offset?: number): Promise<Result<readonly Task[]>> {
return tryCatchAsync(
async () => {
const effectiveLimit = limit ?? SQLiteTaskRepository.DEFAULT_LIMIT;
const effectiveOffset = offset ?? 0;
const stmt = this.db.prepare(`
SELECT * FROM tasks ORDER BY created_at DESC LIMIT ? OFFSET ?
`); // Statement prepared on EVERY call - overhead!
const rows = stmt.all(effectiveLimit, effectiveOffset) as TaskRow[];
return rows.map(row => this.rowToTask(row));
},
operationErrorHandler('find all tasks')
);
}Suggested Fix: Pre-prepare the statement in the constructor: // In constructor (around line 85-90):
this.findAllPaginatedStmt = this.db.prepare(`
SELECT * FROM tasks ORDER BY created_at DESC LIMIT ? OFFSET ?
`);
// In method (replace lines 221-229):
async findAll(limit?: number, offset?: number): Promise<Result<readonly Task[]>> {
return tryCatchAsync(
async () => {
const effectiveLimit = limit ?? SQLiteTaskRepository.DEFAULT_LIMIT;
const effectiveOffset = offset ?? 0;
const rows = this.findAllPaginatedStmt.all(effectiveLimit, effectiveOffset) as TaskRow[];
return rows.map(row => this.rowToTask(row));
},
operationErrorHandler('find all tasks')
);
}Also add the field declaration: // With other statement declarations (around line 82)
private findAllPaginatedStmt: Database.Statement;Performance Impact: Eliminates ~0.1-0.5ms overhead per pagination call from statement compilation. Why: This matches the pattern used for other statements in the repository (e.g., From: performance audit | Severity: HIGH Generated by Claude Code |
|
Performance: Statement preparation inside findAll() method (DependencyRepository) Same issue as TaskRepository: the Current Code ( const stmt = this.db.prepare(`
SELECT * FROM task_dependencies ORDER BY created_at DESC LIMIT ? OFFSET ?
`); // Statement prepared on EVERY call
const rows = stmt.all(effectiveLimit, effectiveOffset) as DependencyRow[];Suggested Fix: Pre-prepare in constructor: // In constructor (around line 105-110):
this.findAllPaginatedStmt = this.db.prepare(`
SELECT * FROM task_dependencies ORDER BY created_at DESC LIMIT ? OFFSET ?
`);
// In method (replace lines 513-516):
const rows = this.findAllPaginatedStmt.all(effectiveLimit, effectiveOffset) as DependencyRow[];Also add field: // With other statement declarations (around line 58-63)
private findAllPaginatedStmt: Database.Statement;Performance Impact: Eliminates ~0.1-0.5ms overhead per pagination call. Why: Matches existing pattern for all other prepared statements. SQLite best practice. From: performance audit | Severity: HIGH Generated by Claude Code |
|
Tests: Missing direct unit tests for TaskRepository pagination The What's Missing: Create describe('TaskRepository.findAll() with pagination', () => {
it('should apply default limit of 100', async () => {
// Create 150 tasks
// Call findAll() with no parameters
// Assert returns exactly 100 tasks
});
it('should respect custom limit parameter', async () => {
// Create 50 tasks
// Call findAll(limit: 25)
// Assert returns exactly 25 tasks
});
it('should respect offset parameter', async () => {
// Create 10 tasks with known order
// Call findAll(limit: 5, offset: 5)
// Assert returns last 5 tasks (skipped first 5)
});
it('should return empty array when offset exceeds count', async () => {
// Create 5 tasks
// Call findAll(limit: 100, offset: 100)
// Assert returns empty array
});
});
describe('TaskRepository.findAllUnbounded()', () => {
it('should return all tasks without limit', async () => {
// Create 200 tasks
// Call findAllUnbounded()
// Assert returns all 200 tasks
});
});
describe('TaskRepository.count()', () => {
it('should return total task count', async () => {
// Create 42 tasks
// Call count()
// Assert returns 42
});
it('should return 0 for empty repository', async () => {
// Empty repository
// Call count()
// Assert returns 0
});
});Why:
Impact: Medium - Code works (verified via integration tests), but violates test quality standards. From: tests audit | Severity: HIGH Generated by Claude Code |
|
Documentation: Missing API documentation for pagination parameters in troubleshooting The Current Documentation ( const allDeps = await dependencyRepo.findAll();
console.log('All dependencies:', allDeps.value);Issue: This code will now only return max 100 dependencies, causing confusion when debugging large dependency graphs. Suggested Fix: Replace with: // Get first page of dependencies (default limit: 100)
const firstPage = await dependencyRepo.findAll();
console.log('First 100 dependencies:', firstPage.value?.length || 0);
// To get ALL dependencies (use sparingly - expensive operation):
const allDeps = await dependencyRepo.findAllUnbounded();
console.log('All dependencies:', allDeps.value?.length || 0);Or create a helper: // Retrieve all dependencies with pagination (memory-safe):
async function getAllDependencies(repo: DependencyRepository) {
const allDeps: TaskDependency[] = [];
let offset = 0;
const limit = 100;
while (true) {
const result = await repo.findAll(limit, offset);
if (!result.ok || result.value.length === 0) break;
allDeps.push(...result.value);
offset += limit;
}
return allDeps;
}
// Usage:
const allDeps = await getAllDependencies(dependencyRepo);
console.log('All dependencies:', allDeps.length);Why:
From: documentation audit | Severity: MEDIUM Generated by Claude Code |
|
Documentation: findAll() JSDoc description is inconsistent The JSDoc description in Current Code ( /**
* Get all dependencies in the system <-- Says "all"
* ...
* @example
* \`\`\`typescript
* const result = await dependencyRepo.findAll();
* if (result.ok) {
* console.log(\`First page has \${result.value.length} dependencies\`); <-- Says "first page"
* }
* \`\`\`
*/Suggested Fix: Update description to clarify pagination: /**
* Get dependencies with optional pagination
*
* Returns up to `limit` dependencies starting from `offset`.
* Useful for pagination UI or memory-constrained environments.
*
* @param limit Maximum results (default: 100)
* @param offset Skip first N results (default: 0)
* @returns Paginated dependency list ordered by created_at DESC
*
* @example
* \`\`\`typescript
* // Get first page of dependencies
* const result = await dependencyRepo.findAll();
* if (result.ok) {
* console.log(\`First page: \${result.value.length} dependencies\`);
* }
*
* // Get specific page
* const page2 = await dependencyRepo.findAll(limit: 100, offset: 100);
* \`\`\`
*/Why: Removes ambiguity. Developers should know immediately that this is paginated, not unbounded. From: documentation audit | Severity: MEDIUM Generated by Claude Code |
|
Tests: TestTaskRepository sorting differs from production The Current Test Double Code ( async findAll(limit?: number, offset?: number): Promise<Result<Task[], Error>> {
const effectiveLimit = limit ?? 100;
const effectiveOffset = offset ?? 0;
const all = Array.from(this.tasks.values());
// NOTE: No sorting by created_at - uses insertion order!
return ok(all.slice(effectiveOffset, effectiveOffset + effectiveLimit));
}Production Implementation ( const stmt = this.db.prepare(`
SELECT * FROM tasks ORDER BY created_at DESC LIMIT ? OFFSET ? // Sorted!
`);Suggested Fix: Add sorting to match production: async findAll(limit?: number, offset?: number): Promise<Result<Task[], Error>> {
const effectiveLimit = limit ?? 100;
const effectiveOffset = offset ?? 0;
const all = Array.from(this.tasks.values())
.sort((a, b) => b.createdAt.getTime() - a.createdAt.getTime()); // Match production sort
return ok(all.slice(effectiveOffset, effectiveOffset + effectiveLimit));
}Why:
From: documentation audit | Severity: MEDIUM Generated by Claude Code |
|
Performance: findByStatus() lacks pagination and should be considered While not in this PR's scope, you've touched the Current Code ( async findByStatus(status: string): Promise<Result<readonly Task[]>> {
return tryCatchAsync(
async () => {
const rows = this.findByStatusStmt.all(status) as TaskRow[]; // No limit!
return rows.map(row => this.rowToTask(row));
},
operationErrorHandler('find tasks by status', { status })
);
}Risk: If many tasks have the same status (e.g., thousands of "pending" tasks), this loads all into memory without limit. Inconsistent with the new pagination pattern. Suggested Approach for Future PR: Add pagination support similar to findAll(): async findByStatus(
status: string,
limit?: number,
offset?: number
): Promise<Result<readonly Task[]>> {
return tryCatchAsync(
async () => {
const effectiveLimit = limit ?? SQLiteTaskRepository.DEFAULT_LIMIT;
const effectiveOffset = offset ?? 0;
const stmt = this.db.prepare(`
SELECT * FROM tasks
WHERE status = ?
ORDER BY created_at DESC
LIMIT ? OFFSET ?
`);
const rows = stmt.all(status, effectiveLimit, effectiveOffset) as TaskRow[];
return rows.map(row => this.rowToTask(row));
},
operationErrorHandler('find tasks by status', { status })
);
}Priority: MEDIUM - Not blocking this PR, but recommend for next iteration to complete API consistency. From: performance audit | Severity: MEDIUM Generated by Claude Code |
|
Security/Robustness: Missing input validation for pagination parameters The Current Code ( const effectiveLimit = limit ?? SQLiteTaskRepository.DEFAULT_LIMIT;
const effectiveOffset = offset ?? 0;
// No bounds checking on limit or offsetAttack Scenario: // Malicious caller
await repository.findAll(limit: Number.MAX_SAFE_INTEGER, offset: 0);
// Attempts to load entire result set into memorySuggested Fix: Add bounds validation: private static readonly MAX_LIMIT = 1000;
private static readonly DEFAULT_LIMIT = 100;
// In findAll():
const effectiveLimit = Math.min(
Math.max(1, limit ?? SQLiteTaskRepository.DEFAULT_LIMIT),
SQLiteTaskRepository.MAX_LIMIT
);
const effectiveOffset = Math.max(0, offset ?? 0);Option: Configurable via constructor if needed: constructor(db: Database, options?: { maxLimit?: number }) {
this.db = db;
this.maxLimit = options?.maxLimit ?? SQLiteTaskRepository.MAX_LIMIT;
}Why:
Current Mitigation: Default limit of 100 protects normal usage, and this method isn't yet exposed via MCP tools. Not a vulnerability, but a good hardening improvement. Priority: LOW - Enhancement, not blocking. From: security & architecture audits | Severity: LOW Generated by Claude Code |
|
Documentation: DependencyHandler architecture comment could be more detailed The comment explaining why Current Code ( // ARCHITECTURE: Use findAllUnbounded() explicitly - we intentionally need ALL dependencies for graph init
handlerLogger.debug('Initializing dependency graph from database');
const allDepsResult = await dependencyRepo.findAllUnbounded();Suggested Enhancement: // ARCHITECTURE: Use findAllUnbounded() explicitly for graph initialization
// RATIONALE: Graph must have complete view of all dependencies for cycle detection
// PERF: One-time O(N) cost at startup; subsequent updates are incremental O(1)
handlerLogger.debug('Initializing dependency graph from database', {
reason: 'graph requires complete dependency view for cycle detection'
});
const allDepsResult = await dependencyRepo.findAllUnbounded();Why:
Priority: LOW - Enhancement, not blocking. Current comment is adequate. From: documentation audit | Severity: LOW Generated by Claude Code |
|
Documentation: DEFAULT_LIMIT constant should be documented in interface The JSDoc for Current Code ( /**
* Find tasks with optional pagination
* @param limit Maximum results (default: 100) <-- What if this changes?
* @param offset Skip first N results (default: 0)
* @returns Paginated task list ordered by created_at DESC
*/
findAll(limit?: number, offset?: number): Promise<Result<readonly Task[]>>;Suggested Fix: Update JSDoc to be more precise: /**
* Find tasks with optional pagination
*
* @param limit Maximum results (default: 100, implementation-defined)
* @param offset Skip first N results (default: 0)
* @returns Paginated task list ordered by created_at DESC, max 1000 records per call
*
* @example
* \`\`\`typescript
* // Get first page (default limit)
* const result = await taskRepo.findAll();
*
* // Get specific page
* const page2 = await taskRepo.findAll(limit: 50, offset: 50);
* \`\`\`
*/
findAll(limit?: number, offset?: number): Promise<Result<readonly Task[]>>;Or add a constant note to the interface: /**
* Find tasks with optional pagination
*
* NOTE: Implementations use DEFAULT_LIMIT=100, MAX_LIMIT=1000.
* See implementation for exact defaults.
*/
findAll(limit?: number, offset?: number): Promise<Result<readonly Task[]>>;Why:
Priority: LOW - Enhancement for clarity. From: documentation audit | Severity: LOW Generated by Claude Code |
|
Tests: Test double lacks complete pagination behavior verification The What Works:
What Differs:
Impact: Tests using this double may not catch ordering bugs when pagination is combined with task creation timing. Suggested Test to Verify: Add this test to validate ordering in the test double: it('TestTaskRepository.findAll should return tasks in created_at DESC order', async () => {
const repo = new TestTaskRepository();
// Create tasks with specific timestamps
const task1 = createTestTask({ createdAt: new Date('2025-01-01') });
const task2 = createTestTask({ createdAt: new Date('2025-01-02') });
const task3 = createTestTask({ createdAt: new Date('2025-01-03') });
await repo.create(task1);
await repo.create(task2);
await repo.create(task3);
// Should return in DESC order (task3, task2, task1)
const result = await repo.findAll();
expect(result.value).toEqual([task3, task2, task1]);
});Notes:
From: tests audit | Severity: MEDIUM (behavior gap) Generated by Claude Code |
PR Code Review SummaryBranch: feature/findall-pagination Results: 14 Review Comments CreatedBy Severity
By Audit Type
Critical Path (Recommended Fix Order)Before Merge - REQUIRED
Before Merge - STRONGLY RECOMMENDED
Good to Have Before Merge
Follow-up PR (Not Blocking)
Quality Metrics
Key Recommendations
Merge RecommendationCONDITIONAL APPROVAL - Approve when:
The branch is technically sound and well-tested. These items ensure behavioral clarity and performance consistency with existing code patterns. Code review generated by Claude Code audit suite |
Fixes from PR #43 code review: Performance: - Pre-compile pagination statements in constructors (task-repository, dependency-repository) - Eliminates ~0.1-0.5ms overhead per pagination call Architecture: - QueryHandler now uses findAllUnbounded() to maintain pre-pagination behavior - Added detailed performance justification comments in DependencyHandler Documentation: - Added CHANGELOG entry for pagination feature with breaking change notice - Updated findByStatus() JSDoc to note it's not paginated - Fixed stale findAll() JSDoc in dependency-repository (was inconsistent) - Updated troubleshooting docs to use findAllUnbounded() - Clarified DEFAULT_LIMIT=100 is a contract in interface JSDoc Tests: - Added 10 new unit tests for TaskRepository pagination - Fixed TestTaskRepository to sort by created_at DESC (matches production) Tech debt items added to Issue #31: - QueryHandler pagination support (proper MCP integration) - findByStatus() pagination - Input validation for pagination parameters 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
1 participant
User description
Summary
This PR implements P1 pre-v0.4.0: Add pagination to findAll() methods across repositories. This prevents unbounded queries from exhausting memory before v0.4.0 adds more tables and more query complexity.
Changes
Features
Paginated findAll(): Added
limitandoffsetparameters with sensible defaults (limit=100, offset=0)Unbounded access for system operations: Added
findAllUnbounded()methodPagination support: Added
count()method to both repositoriesBug Fixes
task-persistence.test.tsthat was passing Task objects tofindAll()instead of IDsRefactoring
Updated DependencyHandler to explicitly call
findAllUnbounded()for graph initialization (line 86)Updated test doubles (MockTaskRepository, MockDependencyRepository) to implement pagination correctly
Breaking Changes
None for internal API - only TaskRepository and DependencyRepository interfaces changed.
However, calling code must migrate:
findAll()without parameters now gets first 100 results (previously all results)findAllUnbounded()Example migration:
Testing
Test Coverage
7 new pagination tests added to dependency-repository.test.ts
Updated 4 test files to use new pagination methods correctly
All Tests Passing
Testing Gaps
None identified. The implementation is straightforward SQL with well-defined behavior.
Security Considerations
Performance Impact
Positive:
Neutral:
Deployment Notes
No special deployment steps needed. This change:
Related Issues
Addresses P1 pre-v0.4.0 priority item: Add pagination before querying multiple tables
Reviewer Focus Areas
Interface contracts (src/core/interfaces.ts lines 87-106, 177-196)
DependencyHandler integration (src/services/handlers/dependency-handler.ts line 86)
Repository implementations (src/implementations/task-repository.ts:215-249, dependency-repository.ts:507-576)
Test coverage (tests/unit/implementations/dependency-repository.test.ts lines 1049-1167)
🤖 Generated with Claude Code
PR Type
Enhancement
Description
Add pagination to
findAll()methods with default limit of 100Introduce
findAllUnbounded()for explicit unbounded accessAdd
count()method for pagination UI supportUpdate DependencyHandler to use
findAllUnbounded()for graph initializationAdd 7 new pagination tests and fix buggy test in task-persistence
Diagram Walkthrough
File Walkthrough
4 files
Add pagination methods to repository interfacesImplement paginated findAll and count methodsImplement paginated findAll and count methodsUse findAllUnbounded for explicit graph initialization5 files
Update test doubles with pagination supportUpdate database failure tests to use findAllUnboundedAdd 7 new pagination and count testsUpdate retry tests to use findAllUnboundedUpdate dependency handler tests to use findAllUnbounded1 files
Fix buggy test and use findAllUnbounded correctly