phase2-architecture.md•8.37 kB
# Phase 2 Architecture: Redis Integration and Scalability
This document outlines the architecture for Phase 2 of the MCP Code Analysis project, focusing on the Redis integration for improved scalability, state persistence, and concurrency handling.
## 1. Architecture Overview
Phase 2 introduces distributed session management using Redis, enabling the MCP server to scale horizontally while maintaining state consistency across instances. The architecture follows a layered approach:

### Key Components
1. **Client Layer**: AI agents and developer tools that interact with the MCP server
2. **API Gateway**: Entry point for requests, handling authentication and routing
3. **Service Layer**: Core business logic implementing the MCP protocol
4. **Persistence Layer**: Redis-backed storage for sessions and state
5. **Execution Layer**: Tools for code analysis, including Rust-based components
## 2. Redis Integration
### 2.1 Session Management
Redis serves as the central repository for session data, replacing the in-memory session store from Phase 1. This enables:
- **Distributed Sessions**: Multiple MCP server instances can share session data
- **Persistence**: Sessions survive server restarts
- **TTL Management**: Automatic expiration of inactive sessions
- **Horizontal Scaling**: Add more server instances without session management concerns
### 2.2 Implementation Details
The `RedisSessionStore` class implements the `SessionStore` interface, providing:
```typescript
// Core session operations
async getSession<T>(sessionId: string): Promise<T | null>;
async setSession<T>(sessionId: string, state: T, ttl?: number): Promise<void>;
async clearSession(sessionId: string): Promise<void>;
async getSessions(): Promise<string[]>;
// Extended capabilities
async acquireLock(sessionId: string, timeout?: number): Promise<string | null>;
async releaseLock(sessionId: string, lockToken: string): Promise<boolean>;
async extendSessionTtl(sessionId: string, ttl: number): Promise<boolean>;
async getSessionTtl(sessionId: string): Promise<number | null>;
async createSessionIfNotExists<T>(sessionId: string, initialState: T): Promise<T>;
```
### 2.3 Concurrency Control
To handle concurrent access to session data, we implement a distributed locking mechanism:
1. **Lock Acquisition**: Before modifying a session, a server instance acquires a lock
2. **Token-Based Locking**: Each lock has a unique token to prevent accidental release
3. **Timeout Mechanism**: Locks automatically expire to prevent deadlocks
4. **Atomic Operations**: Using Redis Lua scripts for atomic lock operations
### 2.4 Data Serialization
Session data is serialized and deserialized when storing in Redis:
- **JSON Serialization**: For structured data
- **Binary Serialization**: For efficient storage of large data structures (using MessagePack)
- **Compression**: For large analysis results
## 3. Enhanced Tool Execution Service
The `RedisToolExecutionService` extends the base implementation with:
### 3.1 State Persistence
- **XState Machine Serialization**: Store and restore state machines
- **Context Persistence**: Maintain execution context across server instances
- **Incremental State Updates**: Optimize state persistence with partial updates
### 3.2 Concurrency Management
- **Distributed Locking**: Prevent concurrent modifications of the same session
- **Optimistic Concurrency**: Version-based conflict resolution for performance
- **Deadlock Prevention**: Lock timeouts and circuit breakers
### 3.3 Failover and Recovery
- **State Recovery**: Rebuild state machines from persisted data
- **Execution Resumption**: Resume interrupted operations
- **Error Handling**: Structured error responses with retry capabilities
## 4. Performance Optimizations
### 4.1 Caching Layer
We implement a multi-level caching strategy:
1. **Local Memory Cache**: For frequently accessed data
2. **Redis Cache**: For shared cache across instances
3. **Cache Invalidation**: Event-based invalidation for consistency
### 4.2 Batched Operations
- **Request Batching**: Group related operations
- **Pipeline Execution**: Redis command pipelining for efficiency
- **Bulk Processing**: Batch tool execution for analysis operations
### 4.3 Connection Pooling
- **Connection Reuse**: Maintain a pool of Redis connections
- **Health Monitoring**: Automatic detection of connection issues
- **Graceful Degradation**: Fallback to local operations when Redis is unavailable
## 5. Redis Configuration
### 5.1 Deployment Options
1. **Single Redis Server**: For development and testing
2. **Redis Sentinel**: For high availability
3. **Redis Cluster**: For horizontal scaling and sharding
### 5.2 Key Structure
We use a standardized key structure for Redis:
- **Session Data**: `{prefix}:session:{sessionId}`
- **Session Locks**: `{prefix}:lock:{sessionId}`
- **Tool Results**: `{prefix}:result:{resultId}`
- **Cache Entries**: `{prefix}:cache:{key}`
### 5.3 Memory Management
- **TTL Policies**: Automatic expiration of unused data
- **Memory Limits**: Configurable memory thresholds
- **Eviction Policies**: LRU-based eviction for memory pressure
## 6. Rust-based Analysis Tools
### 6.1 Tool Integration
We integrate Rust-based analysis tools using:
1. **Child Process Execution**: For standalone tools
2. **WebAssembly**: For browser-compatible tools
3. **FFI**: For direct integration with Node.js
### 6.2 Tool Communication
- **Standardized I/O**: JSON-based input/output
- **Streaming Results**: For large analysis outputs
- **Progress Reporting**: Real-time progress updates
### 6.3 Tool Registry
- **Tool Discovery**: Automatic registration of available tools
- **Version Management**: Tool version tracking
- **Dependency Resolution**: Handle tool dependencies
## 7. Deployment Architecture
### 7.1 Docker Containers
Each component is containerized for easy deployment:
1. **MCP Server**: Node.js application container
2. **Redis**: Redis server container or managed service
3. **Analysis Tools**: Containerized Rust tools
### 7.2 Kubernetes Deployment
For production environments, we provide Kubernetes manifests:
- **Stateless Services**: For MCP server instances
- **StatefulSets**: For Redis instances
- **ConfigMaps**: For configuration
- **Secrets**: For sensitive information
### 7.3 Cloud Deployment
Support for major cloud providers:
- **AWS**: Using ElastiCache for Redis
- **Azure**: Using Azure Cache for Redis
- **GCP**: Using Memorystore
## 8. Monitoring and Observability
### 8.1 Redis Monitoring
- **Connection Health**: Track connection success rates
- **Command Latency**: Measure Redis operation timing
- **Memory Usage**: Monitor memory consumption
### 8.2 Service Metrics
- **Request Rates**: Measure requests per second
- **Response Times**: Track p50, p95, p99 latencies
- **Error Rates**: Monitor failure percentages
### 8.3 Logging
- **Structured Logging**: JSON-formatted logs
- **Correlation IDs**: Track requests across components
- **Log Levels**: Configurable verbosity
## 9. Security Considerations
### 9.1 Redis Security
- **Authentication**: Redis password authentication
- **Network Security**: Secure Redis connections
- **Access Control**: Redis ACL for user management
### 9.2 Data Protection
- **Sensitive Data Handling**: Encryption for sensitive information
- **Data Isolation**: Session isolation between users
- **Data Retention**: Policies for session data retention
## 10. Migration Plan
### 10.1 Gradual Rollout
1. **Development Integration**: Integrate Redis in development
2. **Testing Phase**: Comprehensive testing with Redis
3. **Shadow Mode**: Run Redis alongside existing storage
4. **Gradual Cutover**: Incrementally shift traffic to Redis
### 10.2 Backward Compatibility
- **Interface Compatibility**: Maintain existing APIs
- **Feature Flags**: Toggle Redis integration
- **Fallback Mechanism**: Use local store if Redis is unavailable
## Conclusion
Phase 2 architecture introduces Redis as a central component for session management and state persistence, enabling horizontal scaling while maintaining consistency. The proposed architecture balances performance, scalability, and reliability, providing a solid foundation for the advanced analysis tools planned for Phase 3.