# SPEC-016: Enterprise Logging

## Overview
Complete enterprise-grade logging system with ELK stack integration, multiple output destinations, and comprehensive log management for production environments.

## Components

### Logging Destinations
- **ELK Stack**: Native Elasticsearch, Logstash, Kibana integration
- **Splunk**: Enterprise log management integration
- **Cloud Native**: AWS CloudWatch, Azure Monitor, Google Cloud Logging
- **Prometheus/Grafana**: Metrics and logging integration
- **RabbitMQ Native**: Integration with RabbitMQ's built-in logging
- **AMQP Logging**: Structured logging via AMQP to dedicated logging queues

### Log Management
- **File Rotation**: Daily rotation with size-based rotation (100MB max)
- **Retention Policies**: 30 days for info/debug, 90 days for error/warn, 1 year for audit
- **Compression**: Automatic gzip compression for rotated logs
- **Cleanup**: Automatic deletion of logs exceeding retention periods
- **Archive Options**: Optional archival to S3, Azure Blob, or cloud storage

### Log Categories
- **Application Logs**: MCP server and client operation logs
- **Security Logs**: Authentication, authorization, and security events
- **Performance Logs**: Operation timing, resource usage, and metrics
- **Audit Logs**: Complete audit trail for compliance and governance
- **Error Logs**: Error conditions, exceptions, and failure analysis

### Advanced Features
- **Message Correlation**: UUID-based correlation IDs for tracing
- **Sensitive Data Sanitization**: Automatic redaction of credentials and secrets
- **Log Aggregation**: Centralized log collection and processing
- **Real-time Monitoring**: Real-time log monitoring and alerting
- **Log Analytics**: Advanced log analysis and reporting

### Log Configuration
- **Configurable Outputs**: Multiple output destinations
- **Log Levels**: error, warn, info, debug with configurable thresholds
- **Format Options**: JSON, structured text, and custom formats
- **Filtering**: Advanced log filtering and routing

### Internal Operations (Server Configuration, NOT MCP tools)
**Note**: Logging configuration is server-side, not exposed as MCP tools.

- `logging.configure-output`: Configure log output destinations (server config file)
- `logging.set-level`: Set logging level and thresholds (server config or environment variable)
- `logging.export-logs`: Export logs for analysis (file system operation)
- `logging.get-metrics`: Get logging performance metrics (internal monitoring)

**Constitution Requirement**: Structured logging with configurable destinations (Elasticsearch, Splunk, CloudWatch, etc.)

## Technical Requirements

### Logging Infrastructure
- structlog for structured logging framework
- Multiple output handlers and destinations
- Asynchronous logging for high-throughput scenarios
- Log correlation and tracing capabilities

### Performance
- Logging overhead < 5ms per operation
- Support for 10,000+ log entries per second
- Efficient log serialization and transmission
- Minimal impact on application performance

### Reliability
- Guaranteed log delivery to configured destinations
- Log buffering and retry mechanisms
- Failure handling and fallback options
- Log integrity verification

### Security
- Automatic sanitization of sensitive data
- Secure log transmission and storage
- Access control for log data
- Audit trail for log access

## Acceptance Criteria

### Functional Requirements
- [ ] All logging destinations work correctly
- [ ] Log rotation and retention function properly
- [ ] Log correlation and tracing work accurately
- [ ] Sensitive data sanitization is effective
- [ ] Log aggregation and analysis function correctly

### Performance Requirements
- [ ] Logging overhead under 5ms per operation
- [ ] Supports 10,000+ log entries per second
- [ ] Log transmission is efficient and reliable
- [ ] No performance impact on main operations

### Reliability Requirements
- [ ] Log delivery is guaranteed to all destinations
- [ ] Log buffering and retry mechanisms work
- [ ] Failure handling and fallback options function
- [ ] Log integrity is maintained

### Security Requirements
- [ ] Sensitive data is properly sanitized
- [ ] Log transmission and storage are secure
- [ ] Access control for log data is effective
- [ ] Audit trail for log access is complete

## Dependencies
- structlog for structured logging
- Elasticsearch, Logstash, Kibana for ELK stack
- Cloud provider SDKs for cloud logging
- AMQP libraries for message-based logging

## Implementation Notes
- Use structlog for structured logging framework
- Implement multiple output handlers and destinations
- Set up log correlation and tracing
- Configure automatic log rotation and retention
- Implement sensitive data sanitization
- Set up log aggregation and analysis
- Create log monitoring and alerting
- Implement log security and access control
- Set up log archival and long-term storage
- Create log management and maintenance procedures