feat: v0.3.1 Quick Wins - Atomic Transactions & Input Validation

[dean0x]

User description

Summary

Implements two security and data consistency improvements for the task dependency system:

• Issue [v0.3.1] Multi-Dependency Atomic Transactions #11: Atomic Multi-Dependency Transactions - Prevents partial dependency state
• Issue [v0.3.1] Input Validation Limits for Dependency System #12: Input Validation Limits - Security hardening against DoS attacks

Changes

🔄 Atomic Batch Operations

• New addDependencies() method with all-or-nothing semantics
• Transaction rollback on any validation failure (cycle, duplicate, not found)
• DependencyHandler refactored to use atomic batch operations
• Eliminates partial state when adding multiple dependencies

🔒 Security Hardening

• Maximum 100 dependencies per task (prevents DoS)
• Maximum 100 dependency chain depth (prevents stack overflow)
• Clear error messages with current counts and limits
• New getMaxDepth() algorithm using DFS with memoization

🧪 Test Coverage

• 18 new comprehensive tests (+842 lines)
• Atomic rollback behavior validation
• Large batch operations (50+ dependencies)
• Chain depth calculations
• All 221 unit tests passing

Test plan

• All unit tests pass (npm test - 221 tests)
• Build succeeds (npm run build)
• New validation limits enforced correctly
• Atomic rollback works on failure
• CHANGELOG.md updated

Files Changed

• src/core/interfaces.ts - Added addDependencies() to interface
• src/core/dependency-graph.ts - Added getMaxDepth() algorithm
• src/implementations/dependency-repository.ts - Batch method + validation
• src/services/handlers/dependency-handler.ts - Atomic batch operations
• tests/unit/core/dependency-graph.test.ts - 7 new tests
• tests/unit/implementations/dependency-repository.test.ts - 11 new tests
• CHANGELOG.md - Documented v0.3.1 changes

Closes #11, Closes #12

🤖 Generated with Claude Code

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PR Type

Enhancement, Tests

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Description

• Implements atomic batch dependency operations with all-or-nothing semantics

• Adds input validation limits: max 100 dependencies per task, max 100 chain depth

• New DependencyGraph.getMaxDepth() algorithm using DFS with memoization

• Refactors DependencyHandler to use atomic batch operations for consistency

• Adds 18 comprehensive tests covering rollback, validation, and edge cases

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Diagram Walkthrough

flowchart LR
  A["New addDependencies<br/>Batch Method"] --> B["Atomic Transaction<br/>All-or-Nothing"]
  B --> C["Rollback on<br/>Validation Failure"]
  D["Input Validation<br/>Limits"] --> E["Max 100 Dependencies<br/>per Task"]
  D --> F["Max 100 Chain<br/>Depth"]
  G["getMaxDepth<br/>Algorithm"] --> H["DFS with<br/>Memoization"]
  A --> I["DependencyHandler<br/>Refactored"]
  E --> J["DoS Prevention"]
  F --> K["Stack Overflow<br/>Prevention"]

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File Walkthrough

	Relevant files
Enhancement	dependency-graph.ts Add chain depth calculation algorithm                                        src/core/dependency-graph.ts Added getMaxDepth() method to calculate longest dependency chain from a task Implements DFS algorithm with memoization for O(V+E) complexity Handles cycle detection and diamond-shaped dependency graphs Includes comprehensive JSDoc with examples +73/-0    interfaces.ts Add batch dependency interface method                                        src/core/interfaces.ts Added addDependencies() method signature to DependencyRepository interface Supports atomic batch operations with all-or-nothing semantics Returns array of TaskDependency objects on success +7/-0      dependency-repository.ts Implement atomic batch operations and validation limits    src/implementations/dependency-repository.ts Added security validation: max 100 dependencies per task in addDependency() Added chain depth validation using getMaxDepth() to prevent stack overflow Implemented new addDependencies() method with atomic transaction semantics Uses better-sqlite3 .transaction() for true ACID compliance Comprehensive validation before persisting: cycle detection, duplicates, task existence Includes detailed error messages with current counts and limits +199/-0  dependency-handler.ts Refactor to use atomic batch dependency operations              src/services/handlers/dependency-handler.ts Refactored handleTaskDelegated() to use atomic addDependencies() instead of loop Simplified error handling with single batch operation Maintains event emission for compatibility with existing listeners Updated comments to reflect atomicity guarantees +28/-56
Tests	dependency-graph.test.ts Add comprehensive chain depth calculation tests                    tests/unit/core/dependency-graph.test.ts Added 7 new tests for getMaxDepth() algorithm in new test suite Tests cover: no dependencies, single dependency, linear chains, diamond graphs Includes deep chain test (101 tasks) and memoization performance test Validates correct depth calculation for complex dependency structures +158/-0  dependency-repository.test.ts Add atomic batch and validation limit tests                            tests/unit/implementations/dependency-repository.test.ts Added 3 tests for max dependencies per task validation (100 limit) Added 1 test for max chain depth validation (100 limit) Added 11 tests for atomic batch operations: rollback on cycle, duplicate, not found Tests verify atomicity: no partial state persisted on any failure Includes large batch tests (50+ dependencies) and cache invalidation verification +355/-0
Documentation	CHANGELOG.md Document v0.3.1 features and test coverage                              CHANGELOG.md Documented v0.3.1 security hardening: input validation limits (max 100 deps, max 100 depth) Documented atomic multi-dependency transactions with rollback semantics Added chain depth calculation algorithm documentation Documented 18 new tests and updated test count from 203 to 221 Organized changes by feature with emoji labels for clarity +22/-0

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[qodo-free-for-open-source-projects]

PR Compliance Guide 🔍

(Compliance updated until commit 0d8379b)

Below is a summary of compliance checks for this PR:

Security Compliance
⚪	Missing cycle detection Description: The getMaxDepth() method lacks cycle detection, allowing infinite recursion if a cycle exists in the graph despite the currentPath tracking that is never used to detect cycles. dependency-graph.ts [383-415] Referred Code const calculateDepth = (node: string, currentPath: Set<string>): number => { // Return memoized result if available if (memo.has(node)) { return memo.get(node)!; } const deps = this.graph.get(node); // Leaf node has depth 0 if (!deps || deps.size === 0) { memo.set(node, 0); return 0; } // Track current path for cycle detection currentPath.add(node); // Calculate max depth of all dependencies let maxDepth = 0; for (const dep of deps) { const depth = calculateDepth(dep, currentPath); ... (clipped 12 lines)
	Duplicate dependency bypass Description: The validation checks array length against MAX_DEPENDENCIES_PER_TASK but doesn't prevent a single batch from containing duplicate task IDs, which could bypass the intended limit if the same dependency is listed multiple times. dependency-repository.ts [165-171] Referred Code // Limit to MAX_DEPENDENCIES_PER_TASK for reasonable production workflows if (dependsOn.length > SQLiteDependencyRepository.MAX_DEPENDENCIES_PER_TASK) { return err(new ClaudineError( ErrorCode.INVALID_OPERATION, `Cannot add ${dependsOn.length} dependencies: task cannot have more than ${SQLiteDependencyRepository.MAX_DEPENDENCIES_PER_TASK} dependencies` )); }
Ticket Compliance
🟡	🎫 #12 🟢 Add maximum limit of 100 dependencies per task to prevent DoS attacks Add maximum limit of 100 dependency chain depth to prevent stack overflow Return clear error messages with INVALID_OPERATION error code Provide reasonable limits for production workflows Prevent system instability from deep recursion 🔴 Implement validation in DependencyHandler.addDependency() method Check current dependency count before adding new dependency Check chain depth using transitive closure (getAllDependencies)
🟢	🎫 #11 🟢 Wrap multiple dependency additions in single atomic transaction Prevent partial state when adding multiple dependencies fails mid-way Implement addDependencies() method that accepts array of TaskIds Use database transaction to ensure all succeed or all fail atomically Provide rollback capability on failure Ensure consistency for complex dependency chains Better error handling with automatic rollback
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: Passed Learn more about managing compliance generic rules or creating your own custom rules

Compliance status legend

🟢 - Fully Compliant
🟡 - Partial Compliant
🔴 - Not Compliant
⚪ - Requires Further Human Verification
🏷️ - Compliance label

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Previous compliance checks

Compliance check up to commit d85f619

Security Compliance
🟢	No security concerns identified No security vulnerabilities detected by AI analysis. Human verification advised for critical code.
Ticket Compliance
🟢	🎫 #11 🟢 Wrap multiple dependency additions in single atomic transaction Prevent partial state when adding multiple dependencies All dependencies succeed or all fail atomically Better error handling with rollback on failure Ensures consistency for complex dependency chains
🟢	🎫 #12 🟢 Add max 100 dependencies per task limit to prevent DoS attacks Add max 100 dependency chain depth to prevent stack overflow Check current dependency count before adding Check chain depth using transitive closure Provide clear error messages for users hitting limits
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: Passed Learn more about managing compliance generic rules or creating your own custom rules

[qodo-free-for-open-source-projects]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
High-level	Refactor to eliminate duplicate logic Refactor the addDependency method to call the new addDependencies method with a single dependency. This will remove duplicated validation logic and centralize it within addDependencies. Examples: src/implementations/dependency-repository.ts [112-238] async addDependency(taskId: TaskId, dependsOnTaskId: TaskId): Promise<Result<TaskDependency>> { // SECURITY: TOCTOU Fix - Use synchronous .transaction() for true atomicity // Per Wikipedia TOCTOU principles: check and use must be atomic // better-sqlite3's .transaction() ensures no JavaScript event loop interleaving // Rationale: Async functions with BEGIN/COMMIT allow race conditions const addDependencyTransaction = this.db.transaction((taskId: TaskId, dependsOnTaskId: TaskId) => { // ALL operations below are synchronous - no await, no yielding to event loop // This guarantees atomicity: no other transaction can interleave // VALIDATION: Check both tasks exist (foreign key validation) ... (clipped 117 lines) src/implementations/dependency-repository.ts [265-414] async addDependencies(taskId: TaskId, dependsOn: readonly TaskId[]): Promise<Result<readonly TaskDependency[]>> { // VALIDATION: Reject empty arrays if (dependsOn.length === 0) { return err(new ClaudineError( ErrorCode.INVALID_OPERATION, 'Cannot add dependencies: empty array provided' )); } // SECURITY: Prevent DoS attacks with excessive dependencies ... (clipped 140 lines) Solution Walkthrough: Before: class SQLiteDependencyRepository { async addDependency(taskId, dependsOnTaskId) { // ... transaction start // ... validation: task exists // ... validation: max deps // ... validation: dependency exists // ... validation: cycle check // ... validation: depth check // ... insert single dependency // ... transaction end } async addDependencies(taskId, dependsOn) { // ... transaction start // ... validation: task exists // ... validation: max deps // ... loop over dependsOn: // ... validation: dependency exists // ... validation: cycle check // ... validation: depth check // ... loop over dependsOn to insert // ... transaction end } } After: class SQLiteDependencyRepository { async addDependency(taskId, dependsOnTaskId) { const result = await this.addDependencies(taskId, [dependsOnTaskId]); if (result.ok) { return ok(result.value[0]); } return result; } async addDependencies(taskId, dependsOn) { // ... transaction start // ... validation: task exists // ... validation: max deps // ... loop over dependsOn: // ... validation: dependency exists // ... validation: cycle check // ... validation: depth check // ... loop over dependsOn to insert // ... transaction end } } Suggestion importance[1-10]: 7 __ Why: The suggestion correctly identifies significant duplication of complex validation logic between addDependency and addDependencies, and the proposed refactoring would centralize this logic, improving maintainability.	Medium
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