Design Patterns MCP Server

{ "id": "circuit-breaker", "name": "Circuit Breaker", "category": "Cloud-Native", "description": "Prevents cascading failures by failing fast when service is unavailable", "when_to_use": "Distributed systems\nExternal service calls\nFault tolerance", "benefits": "Fail fast\nSystem stability\nResource protection\nGraceful degradation", "drawbacks": "Additional complexity\nConfiguration tuning\nFalse positives", "use_cases": "Microservices\nAPI gateways\nExternal integrations", "complexity": "Medium", "tags": [ "fault-tolerance", "resilience", "microservices" ], "examples": { "typescript": { "language": "typescript", "code": "// Circuit Breaker: prevent cascading failures\nenum CircuitState { CLOSED, OPEN, HALF_OPEN }\n\nclass CircuitBreaker {\n private state = CircuitState.CLOSED;\n private failures = 0;\n private threshold = 5;\n \n async execute<T>(fn: () => Promise<T>): Promise<T> {\n if (this.state === CircuitState.OPEN) {\n throw new Error('Circuit breaker is OPEN');\n }\n \n try {\n const result = await fn();\n this.onSuccess();\n return result;\n } catch (error) {\n this.onFailure();\n throw error;\n }\n }\n \n private onSuccess() {\n this.failures = 0;\n this.state = CircuitState.CLOSED;\n }\n \n private onFailure() {\n this.failures++;\n if (this.failures >= this.threshold) {\n this.state = CircuitState.OPEN;\n }\n }\n}\n\nconst breaker = new CircuitBreaker();\nawait breaker.execute(() => fetch('https://api.example.com'));" } } }