Neo4j Memory Server

/** * Comprehensive test suite for MCP error handling system * Covers all error classes, Neo4j error detection, and error conversion utilities */ import { describe, it, expect } from 'vitest'; import { MCPError, MCPValidationError, MCPDatabaseError, MCPServiceError, MCPResourceNotFoundError, MCPOperationError, detectNeo4jError, isMCPError, toMCPError, } from '../../../../src/infrastructure/errors/mcp-errors'; import { MCPErrorCodes } from '../../../../src/infrastructure/errors/error-codes'; describe('MCP Error System', () => { describe('MCPValidationError', () => { it('should create validation error with default code', () => { const error = new MCPValidationError('Invalid input'); expect(error.message).toBe('Invalid input'); expect(error.code).toBe(MCPErrorCodes.VALIDATION_FAILED); expect(error.name).toBe('MCPValidationError'); expect(error.data).toBeUndefined(); }); it('should create validation error with custom code and data', () => { const data = { field: 'email', value: 'invalid-email' }; const error = new MCPValidationError( 'Email validation failed', MCPErrorCodes.INVALID_ID_FORMAT, data ); expect(error.message).toBe('Email validation failed'); expect(error.code).toBe(MCPErrorCodes.INVALID_ID_FORMAT); expect(error.data).toEqual(data); }); it('should convert to JSON-RPC format', () => { const error = new MCPValidationError('Test error', MCPErrorCodes.VALIDATION_FAILED); const jsonRpc = error.toJsonRpc(); expect(jsonRpc).toEqual({ code: MCPErrorCodes.VALIDATION_FAILED, message: 'Test error' }); }); it('should include data in JSON-RPC format when present', () => { const data = { details: 'additional info' }; const error = new MCPValidationError('Test error', MCPErrorCodes.VALIDATION_FAILED, data); const jsonRpc = error.toJsonRpc(); expect(jsonRpc).toEqual({ code: MCPErrorCodes.VALIDATION_FAILED, message: 'Test error', data }); }); }); describe('MCPDatabaseError', () => { it('should create database error with default code', () => { const error = new MCPDatabaseError('Connection failed'); expect(error.message).toBe('Connection failed'); expect(error.code).toBe(MCPErrorCodes.DATABASE_OPERATION_FAILED); expect(error.name).toBe('MCPDatabaseError'); }); it('should create database error with custom code', () => { const error = new MCPDatabaseError( 'Database not found', MCPErrorCodes.DATABASE_NOT_FOUND ); expect(error.code).toBe(MCPErrorCodes.DATABASE_NOT_FOUND); }); }); describe('MCPServiceError', () => { it('should create service error with default code', () => { const error = new MCPServiceError('Service unavailable'); expect(error.message).toBe('Service unavailable'); expect(error.code).toBe(MCPErrorCodes.SERVICE_UNAVAILABLE); expect(error.name).toBe('MCPServiceError'); }); it('should create service error with custom code', () => { const error = new MCPServiceError( 'GDS plugin missing', MCPErrorCodes.GDS_PLUGIN_MISSING ); expect(error.code).toBe(MCPErrorCodes.GDS_PLUGIN_MISSING); }); }); describe('MCPResourceNotFoundError', () => { it('should create resource not found error with formatted message', () => { const error = new MCPResourceNotFoundError('Memory', 'test-id-123'); expect(error.message).toBe('Memory not found: test-id-123'); expect(error.code).toBe(MCPErrorCodes.MEMORY_NOT_FOUND); expect(error.data).toEqual({ resourceType: 'Memory', resourceId: 'test-id-123' }); }); it('should create resource not found error with custom code', () => { const error = new MCPResourceNotFoundError( 'Database', 'test-db', MCPErrorCodes.DATABASE_NOT_FOUND ); expect(error.code).toBe(MCPErrorCodes.DATABASE_NOT_FOUND); }); }); describe('MCPOperationError', () => { it('should create operation error with default code', () => { const error = new MCPOperationError('Operation timeout'); expect(error.message).toBe('Operation timeout'); expect(error.code).toBe(MCPErrorCodes.OPERATION_TIMEOUT); expect(error.name).toBe('MCPOperationError'); }); it('should create operation error with custom code and data', () => { const data = { timeout: 5000, operation: 'search' }; const error = new MCPOperationError( 'Search timeout', MCPErrorCodes.OPERATION_TIMEOUT, data ); expect(error.code).toBe(MCPErrorCodes.OPERATION_TIMEOUT); expect(error.data).toEqual(data); }); }); describe('detectNeo4jError', () => { it('should return null for non-Error objects', () => { const result = detectNeo4jError('string error'); expect(result).toBeNull(); }); it('should return null for generic errors', () => { const error = new Error('Generic error message'); const result = detectNeo4jError(error); expect(result).toBeNull(); }); it('should detect constraint validation errors', () => { const error = new Error( "ConstraintValidationFailed: Node(123) already exists with label `Memory` and property `id` = 'dZ$test123456789abc'" ); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result?.message).toBe('Duplicate ID constraint violation: dZ$test123456789abc'); expect(result?.code).toBe(MCPErrorCodes.DUPLICATE_ID); expect(result?.data).toEqual({ duplicateId: 'dZ$test123456789abc' }); }); it('should detect service unavailable errors', () => { const error = new Error('ServiceUnavailable: Database connection lost'); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result?.message).toBe('Database service unavailable'); expect(result?.code).toBe(MCPErrorCodes.DATABASE_UNAVAILABLE); }); it('should detect connection refused errors', () => { const error = new Error('Connection refused: Could not connect to database'); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result?.message).toBe('Database service unavailable'); }); it('should detect database not found errors', () => { const error = new Error("Database does not exist"); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result?.message).toBe('Database not found: unknown'); expect(result?.code).toBe(MCPErrorCodes.DATABASE_NOT_FOUND); expect(result?.data).toEqual({ database: 'unknown' }); }); it('should detect GDS function errors', () => { const error = new Error("Unknown function 'gds.similarity.cosine'"); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPServiceError); expect(result?.message).toBe('Neo4j Graph Data Science (GDS) plugin is required but not installed'); expect(result?.code).toBe(MCPErrorCodes.GDS_PLUGIN_MISSING); expect(result?.data).toEqual({ function: 'gds.similarity.cosine', installUrl: 'https://dozerdb.org/', verifyCommand: 'RETURN gds.similarity.cosine([1,2,3], [2,3,4])' }); }); it('should detect non-GDS unknown function errors', () => { const error = new Error("Unknown function 'custom.function'"); const result = detectNeo4jError(error); expect(result).toBeNull(); }); it('should handle constraint error without ID match', () => { const error = new Error("ConstraintValidationFailed: Generic constraint violation"); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result?.message).toBe('Duplicate ID constraint violation: unknown'); expect(result?.data).toEqual({ duplicateId: 'unknown' }); }); it('should handle database error without name match', () => { const error = new Error("Database does not exist"); const result = detectNeo4jError(error); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result?.message).toBe('Database not found: unknown'); expect(result?.data).toEqual({ database: 'unknown' }); }); }); describe('isMCPError', () => { it('should return true for MCP error instances', () => { const error = new MCPValidationError('test'); expect(isMCPError(error)).toBe(true); }); it('should return true for all MCP error subclasses', () => { const errors = [ new MCPValidationError('test'), new MCPDatabaseError('test'), new MCPServiceError('test'), new MCPResourceNotFoundError('Memory', 'test-id'), new MCPOperationError('test') ]; errors.forEach(error => { expect(isMCPError(error)).toBe(true); }); }); it('should return false for non-MCP errors', () => { expect(isMCPError(new Error('generic error'))).toBe(false); expect(isMCPError('string')).toBe(false); expect(isMCPError(null)).toBe(false); expect(isMCPError(undefined)).toBe(false); expect(isMCPError({})).toBe(false); }); }); describe('toMCPError', () => { it('should return same error if already MCP error', () => { const originalError = new MCPValidationError('test'); const result = toMCPError(originalError); expect(result).toBe(originalError); }); it('should convert Neo4j errors to appropriate MCP errors', () => { const neo4jError = new Error("ServiceUnavailable: Connection lost"); const result = toMCPError(neo4jError); expect(result).toBeInstanceOf(MCPDatabaseError); expect(result.message).toBe('Database service unavailable'); }); it('should convert generic Error to MCPOperationError', () => { const genericError = new Error('Something went wrong'); const result = toMCPError(genericError); expect(result).toBeInstanceOf(MCPOperationError); expect(result.message).toBe('Something went wrong'); expect(result.code).toBe(MCPErrorCodes.INTERNAL_ERROR); expect(result.data).toEqual({ originalError: 'Error' }); }); it('should convert string to MCPOperationError', () => { const stringError = 'String error message'; const result = toMCPError(stringError); expect(result).toBeInstanceOf(MCPOperationError); expect(result.message).toBe('String error message'); expect(result.code).toBe(MCPErrorCodes.INTERNAL_ERROR); expect(result.data).toEqual({ originalError: 'String error message' }); }); it('should convert null/undefined to MCPOperationError', () => { const nullResult = toMCPError(null); const undefinedResult = toMCPError(undefined); expect(nullResult).toBeInstanceOf(MCPOperationError); expect(nullResult.message).toBe('null'); expect(undefinedResult).toBeInstanceOf(MCPOperationError); expect(undefinedResult.message).toBe('undefined'); }); it('should convert objects to MCPOperationError', () => { const objectError = { type: 'custom', message: 'Custom error' }; const result = toMCPError(objectError); expect(result).toBeInstanceOf(MCPOperationError); expect(result.message).toBe('[object Object]'); expect(result.data).toEqual({ originalError: objectError }); }); }); describe('Error inheritance and instanceof checks', () => { it('should maintain proper inheritance hierarchy', () => { const errors = [ new MCPValidationError('test'), new MCPDatabaseError('test'), new MCPServiceError('test'), new MCPResourceNotFoundError('Memory', 'test-id'), new MCPOperationError('test') ]; errors.forEach(error => { expect(error).toBeInstanceOf(MCPError); expect(error).toBeInstanceOf(Error); }); }); it('should have correct constructor names', () => { const errors = [ { error: new MCPValidationError('test'), name: 'MCPValidationError' }, { error: new MCPDatabaseError('test'), name: 'MCPDatabaseError' }, { error: new MCPServiceError('test'), name: 'MCPServiceError' }, { error: new MCPResourceNotFoundError('Memory', 'test-id'), name: 'MCPResourceNotFoundError' }, { error: new MCPOperationError('test'), name: 'MCPOperationError' } ]; errors.forEach(({ error, name }) => { expect(error.name).toBe(name); expect(error.constructor.name).toBe(name); }); }); }); describe('JSON-RPC conversion edge cases', () => { it('should not include data field when data is undefined', () => { const error = new MCPValidationError('test'); const jsonRpc = error.toJsonRpc(); expect(jsonRpc).not.toHaveProperty('data'); expect(Object.keys(jsonRpc)).toEqual(['code', 'message']); }); it('should include data field when data is null', () => { const error = new MCPValidationError('test', MCPErrorCodes.VALIDATION_FAILED, null); const jsonRpc = error.toJsonRpc(); expect(jsonRpc).toHaveProperty('data', null); }); it('should include data field when data is false', () => { const error = new MCPValidationError('test', MCPErrorCodes.VALIDATION_FAILED, false); const jsonRpc = error.toJsonRpc(); expect(jsonRpc).toHaveProperty('data', false); }); it('should include data field when data is empty object', () => { const error = new MCPValidationError('test', MCPErrorCodes.VALIDATION_FAILED, {}); const jsonRpc = error.toJsonRpc(); expect(jsonRpc).toHaveProperty('data', {}); }); }); });