# API Server Services - Business Requirements

**Document Version**: 1.0
**Date**: January 2025
**Status**: Business Requirements Specification
**Module**: API Server Services (`pkg/api/server/`)

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## 1. Purpose & Scope

### 1.1 Business Purpose
The API Server Services layer provides high-performance, secure, and scalable HTTP API endpoints that enable external systems, HolmesGPT integration, and user interfaces to interact with Kubernaut's intelligent remediation capabilities through well-defined RESTful interfaces with enterprise-grade reliability and security.

### 1.2 Scope
- **Context API Server**: HolmesGPT dynamic context orchestration and toolset integration
- **RESTful API Services**: Standard HTTP endpoints for all Kubernaut functionality
- **API Gateway Integration**: Enterprise API management and security
- **Real-time Communication**: WebSocket and Server-Sent Events for live updates
- **Service Mesh Integration**: Kubernetes-native service communication

---

## 2. Context API Server

### 2.1 Business Capabilities

#### 2.1.1 HolmesGPT Integration
- **BR-CAPI-001**: MUST provide dynamic context orchestration API for HolmesGPT toolset integration
- **BR-CAPI-002**: MUST support real-time context retrieval with <100ms response time for cached requests
- **BR-CAPI-003**: MUST implement intelligent context caching with 80%+ cache hit rates
- **BR-CAPI-004**: MUST provide context relevance scoring with 85-95% accuracy
- **BR-CAPI-005**: MUST support context API versioning and backward compatibility

#### 2.1.2 Dynamic Context Orchestration
- **BR-CAPI-006**: MUST orchestrate context retrieval from multiple sources (Kubernetes, logs, metrics)
- **BR-CAPI-007**: MUST implement AI-driven context prioritization and filtering
- **BR-CAPI-008**: MUST support parallel context gathering with intelligent aggregation
- **BR-CAPI-009**: MUST provide context customization based on investigation type
- **BR-CAPI-010**: MUST implement context streaming for large result sets

#### 2.1.3 Performance Optimization
- **BR-CAPI-011**: MUST achieve 40-60% investigation time reduction vs. static enrichment
- **BR-CAPI-012**: MUST reduce memory utilization by 50-70% through intelligent caching
- **BR-CAPI-013**: MUST support 100+ concurrent context requests per second
- **BR-CAPI-014**: MUST implement request prioritization based on investigation criticality
- **BR-CAPI-015**: MUST provide context prefetching for predictive performance

#### 2.1.4 Integration Management
- **BR-CAPI-016**: MUST integrate seamlessly with HolmesGPT custom toolset framework
- **BR-CAPI-017**: MUST support multiple concurrent HolmesGPT instances
- **BR-CAPI-018**: MUST provide API authentication and authorization for external access
- **BR-CAPI-019**: MUST implement rate limiting and throttling for fair resource usage
- **BR-CAPI-020**: MUST support API metrics and observability for performance monitoring

---

## 3. RESTful API Services

### 3.1 Business Capabilities

#### 3.1.1 Core API Endpoints
- **BR-API-001**: MUST provide comprehensive REST API for all Kubernaut functionality
- **BR-API-002**: MUST implement OpenAPI 3.0 specification with complete documentation
- **BR-API-003**: MUST support JSON and YAML content types for all endpoints
- **BR-API-004**: MUST provide consistent error handling and status codes
- **BR-API-005**: MUST implement API versioning with semantic versioning standards

#### 3.1.2 Workflow Management API
- **BR-API-006**: MUST provide endpoints for workflow creation, execution, and monitoring
- **BR-API-007**: MUST support workflow template management and versioning
- **BR-API-008**: MUST implement workflow status tracking and real-time updates
- **BR-API-009**: MUST provide workflow history and audit trail access
- **BR-API-010**: MUST support batch workflow operations and bulk management

#### 3.1.3 AI & Intelligence API
- **BR-API-011**: MUST provide endpoints for AI model training and inference
- **BR-API-012**: MUST support pattern discovery and anomaly detection queries
- **BR-API-013**: MUST implement AI insights and recommendations access
- **BR-API-014**: MUST provide AI model performance metrics and evaluation
- **BR-API-015**: MUST support AI configuration and parameter management

#### 3.1.4 Platform Operations API
- **BR-API-016**: MUST provide endpoints for Kubernetes action execution and status
- **BR-API-017**: MUST support infrastructure monitoring and metrics access
- **BR-API-018**: MUST implement platform health checks and diagnostics
- **BR-API-019**: MUST provide security and compliance reporting endpoints
- **BR-API-020**: MUST support system configuration and management operations

---

## 4. API Security & Authentication

### 4.1 Business Capabilities

#### 4.1.1 Authentication & Authorization
- **BR-SEC-001**: MUST implement OAuth 2.0 and JWT token-based authentication
- **BR-SEC-002**: MUST support API key authentication for service-to-service communication
- **BR-SEC-003**: MUST integrate with enterprise identity providers (LDAP, SAML, OIDC)
- **BR-SEC-004**: MUST implement role-based access control for all API endpoints
- **BR-SEC-005**: MUST provide multi-factor authentication for administrative operations

#### 4.1.2 API Security Controls
- **BR-SEC-006**: MUST implement comprehensive input validation and sanitization
- **BR-SEC-007**: MUST provide rate limiting and DDoS protection mechanisms
- **BR-SEC-008**: MUST support CORS configuration for web application integration
- **BR-SEC-009**: MUST implement API request/response encryption with TLS 1.3
- **BR-SEC-010**: MUST provide security headers and vulnerability protection

#### 4.1.3 Audit & Compliance
- **BR-SEC-011**: MUST log all API access attempts with comprehensive audit trails
- **BR-SEC-012**: MUST implement request correlation and distributed tracing
- **BR-SEC-013**: MUST provide compliance reporting for regulatory requirements
- **BR-SEC-014**: MUST support data privacy and anonymization for logs
- **BR-SEC-015**: MUST implement security incident detection and alerting

#### 4.1.4 Certificate & Key Management
- **BR-SEC-016**: MUST support mutual TLS authentication for high-security environments
- **BR-SEC-017**: MUST implement automatic certificate rotation and renewal
- **BR-SEC-018**: MUST provide secure key storage and hardware security module integration
- **BR-SEC-019**: MUST support certificate-based client authentication
- **BR-SEC-020**: MUST implement certificate validation and revocation checking

---

## 5. API Performance & Scalability

### 5.1 Business Capabilities

#### 5.1.1 High-Performance API
- **BR-PERF-001**: MUST support 10,000+ concurrent API connections
- **BR-PERF-002**: MUST achieve <500ms response time for 95% of API requests
- **BR-PERF-003**: MUST implement efficient connection pooling and keep-alive
- **BR-PERF-004**: MUST support HTTP/2 and HTTP/3 for improved performance
- **BR-PERF-005**: MUST provide response compression and optimization

#### 5.1.2 Scalability & Load Balancing
- **BR-PERF-006**: MUST support horizontal scaling with load balancer integration
- **BR-PERF-007**: MUST implement health checks for automatic failover
- **BR-PERF-008**: MUST support session affinity and stateless operations
- **BR-PERF-009**: MUST provide auto-scaling based on API load metrics
- **BR-PERF-010**: MUST support geographic distribution and edge deployment

#### 5.1.3 Caching & Optimization
- **BR-PERF-011**: MUST implement intelligent response caching with configurable TTL
- **BR-PERF-012**: MUST support CDN integration for static content delivery
- **BR-PERF-013**: MUST provide API response optimization and minification
- **BR-PERF-014**: MUST implement efficient database query optimization
- **BR-PERF-015**: MUST support batch operations to reduce API call overhead

#### 5.1.4 Resource Management
- **BR-PERF-016**: MUST implement resource quotas and fair usage policies
- **BR-PERF-017**: MUST provide memory and CPU optimization for API services
- **BR-PERF-018**: MUST support graceful degradation under high load
- **BR-PERF-019**: MUST implement circuit breakers for external dependencies
- **BR-PERF-020**: MUST provide resource monitoring and capacity planning

---

## 6. API Documentation & Developer Experience

### 6.1 Business Capabilities

#### 6.1.1 Comprehensive Documentation
- **BR-DOC-001**: MUST provide interactive API documentation with live examples
- **BR-DOC-002**: MUST implement API playground for testing and exploration
- **BR-DOC-003**: MUST provide SDK generation for multiple programming languages
- **BR-DOC-004**: MUST include comprehensive code examples and tutorials
- **BR-DOC-005**: MUST maintain up-to-date API reference documentation

#### 6.1.2 Developer Tools & Integration
- **BR-DOC-006**: MUST provide Postman collections and API testing tools
- **BR-DOC-007**: MUST support API mocking and testing environments
- **BR-DOC-008**: MUST implement API schema validation and contract testing
- **BR-DOC-009**: MUST provide client library installation and configuration guides
- **BR-DOC-010**: MUST support API versioning migration guides and changelogs

#### 6.1.3 API Governance & Standards
- **BR-DOC-011**: MUST implement consistent API design patterns and conventions
- **BR-DOC-012**: MUST provide API lifecycle management and deprecation policies
- **BR-DOC-013**: MUST support API contract testing and validation
- **BR-DOC-014**: MUST implement API quality gates and review processes
- **BR-DOC-015**: MUST provide API analytics and usage insights

#### 6.1.4 Support & Community
- **BR-DOC-016**: MUST provide developer support channels and forums
- **BR-DOC-017**: MUST implement feedback collection and issue tracking
- **BR-DOC-018**: MUST support community contributions and API improvements
- **BR-DOC-019**: MUST provide developer onboarding and certification programs
- **BR-DOC-020**: MUST maintain active developer community engagement

---

## 7. Real-time Communication

### 7.1 Business Capabilities

#### 7.1.1 WebSocket Services
- **BR-WS-001**: MUST provide WebSocket endpoints for real-time workflow updates
- **BR-WS-002**: MUST support real-time alert and event streaming
- **BR-WS-003**: MUST implement real-time dashboard and metrics updates
- **BR-WS-004**: MUST provide collaborative features for multi-user scenarios
- **BR-WS-005**: MUST support WebSocket authentication and authorization

#### 7.1.2 Server-Sent Events
- **BR-SSE-001**: MUST implement Server-Sent Events for push notifications
- **BR-SSE-002**: MUST support event filtering and subscription management
- **BR-SSE-003**: MUST provide event history and replay capabilities
- **BR-SSE-004**: MUST implement event prioritization and delivery guarantees
- **BR-SSE-005**: MUST support cross-origin resource sharing for web clients

#### 7.1.3 Message Queuing Integration
- **BR-MQ-001**: MUST integrate with message queuing systems for reliable delivery
- **BR-MQ-002**: MUST support event-driven architecture patterns
- **BR-MQ-003**: MUST implement message persistence and replay capabilities
- **BR-MQ-004**: MUST provide message routing and topic-based subscriptions
- **BR-MQ-005**: MUST support message ordering and exactly-once delivery

#### 7.1.4 Real-time Analytics
- **BR-RT-001**: MUST provide real-time API usage metrics and analytics
- **BR-RT-002**: MUST implement real-time performance monitoring dashboards
- **BR-RT-003**: MUST support real-time alerting for API health and performance
- **BR-RT-004**: MUST provide real-time user activity and engagement tracking
- **BR-RT-005**: MUST implement real-time capacity and resource monitoring

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## 8. Enterprise Integration & Standards

### 8.1 Business Capabilities

#### 8.1.1 Enterprise API Gateway
- **BR-GATE-001**: MUST integrate with enterprise API gateway solutions
- **BR-GATE-002**: MUST support API management platforms (Kong, Ambassador, Istio)
- **BR-GATE-003**: MUST implement service mesh integration for microservices
- **BR-GATE-004**: MUST provide API discovery and service registry integration
- **BR-GATE-005**: MUST support API transformation and protocol translation

#### 8.1.2 Standards Compliance
- **BR-STD-001**: MUST comply with OpenAPI 3.0 specification standards
- **BR-STD-002**: MUST implement REST architectural principles and best practices
- **BR-STD-003**: MUST support GraphQL for flexible data querying
- **BR-STD-004**: MUST comply with JSON API specification for consistency
- **BR-STD-005**: MUST implement HTTP/2 and HTTP/3 protocol support

#### 8.1.3 Enterprise Security
- **BR-ENT-001**: MUST integrate with enterprise security policies and frameworks
- **BR-ENT-002**: MUST support enterprise certificate authorities and PKI
- **BR-ENT-003**: MUST implement enterprise audit and compliance requirements
- **BR-ENT-004**: MUST provide enterprise-grade monitoring and observability
- **BR-ENT-005**: MUST support enterprise backup and disaster recovery

#### 8.1.4 Cloud Native Integration
- **BR-CLOUD-001**: MUST support Kubernetes-native service discovery and networking
- **BR-CLOUD-002**: MUST implement cloud provider integration (AWS, Azure, GCP)
- **BR-CLOUD-003**: MUST support container orchestration and lifecycle management
- **BR-CLOUD-004**: MUST provide cloud-native monitoring and logging integration
- **BR-CLOUD-005**: MUST implement cloud-native security and compliance features

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## 9. Performance Requirements

### 9.1 API Response Performance
- **BR-PERF-021**: Context API MUST respond within 100ms for 95% of cached requests
- **BR-PERF-022**: Context API MUST respond within 500ms for 95% of fresh requests
- **BR-PERF-023**: Standard API endpoints MUST respond within 200ms for 95% of requests
- **BR-PERF-024**: Complex queries MUST respond within 2 seconds for 95% of requests
- **BR-PERF-025**: Bulk operations MUST process 1000+ items per minute

### 9.2 Concurrency & Throughput
- **BR-PERF-026**: MUST support 10,000+ concurrent API connections
- **BR-PERF-027**: MUST handle 50,000+ API requests per minute
- **BR-PERF-028**: MUST support 1000+ concurrent WebSocket connections
- **BR-PERF-029**: MUST maintain performance under 10x normal load
- **BR-PERF-030**: MUST provide linear scaling with additional server instances

### 9.3 Resource Utilization
- **BR-PERF-031**: API services MUST utilize <80% of allocated CPU resources
- **BR-PERF-032**: Memory usage MUST remain under 4GB per API server instance
- **BR-PERF-033**: Network bandwidth MUST be optimized for minimum latency
- **BR-PERF-034**: Database connections MUST be efficiently pooled and managed
- **BR-PERF-035**: Cache hit rates MUST exceed 80% for frequently accessed data

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## 10. Reliability & Availability Requirements

### 10.1 High Availability
- **BR-REL-001**: API services MUST maintain 99.95% uptime availability
- **BR-REL-002**: MUST support zero-downtime deployments and updates
- **BR-REL-003**: MUST implement automatic failover with <30 second recovery
- **BR-REL-004**: MUST provide health checks and readiness probes
- **BR-REL-005**: MUST support active-active clustering for high availability

### 10.2 Fault Tolerance
- **BR-REL-006**: MUST implement graceful degradation during partial failures
- **BR-REL-007**: MUST provide circuit breakers for external dependencies
- **BR-REL-008**: MUST support request retry mechanisms with exponential backoff
- **BR-REL-009**: MUST implement bulkhead patterns for resource isolation
- **BR-REL-010**: MUST provide comprehensive error handling and recovery

### 10.3 Disaster Recovery
- **BR-REL-011**: MUST support cross-region deployment for disaster recovery
- **BR-REL-012**: MUST implement data backup and recovery procedures
- **BR-REL-013**: MUST provide RTO <1 hour and RPO <15 minutes
- **BR-REL-014**: MUST support database replication and synchronization
- **BR-REL-015**: MUST implement automated disaster recovery testing

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## 11. Success Criteria

### 11.1 Technical Success
- API services operate with 99.95% availability and <500ms response times
- Context API achieves 40-60% investigation time reduction for HolmesGPT
- Comprehensive API documentation enables rapid developer onboarding
- Security controls prevent unauthorized access and protect sensitive data
- Real-time communication supports collaborative and responsive user experiences

### 11.2 Integration Success
- Seamless HolmesGPT integration with intelligent context orchestration
- Enterprise API gateway integration supports organizational security policies
- Multi-language SDK support enables broad developer ecosystem adoption
- Cloud-native deployment supports scalable, resilient production operations
- Standards compliance ensures interoperability with existing enterprise systems

### 11.3 Business Success
- API services enable external integrations and ecosystem expansion
- Developer-friendly APIs accelerate partner and customer integration
- Enterprise-grade security and compliance support organizational requirements
- High-performance APIs support business-critical operations and SLAs
- API analytics provide insights for continuous improvement and optimization

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*This document serves as the definitive specification for business requirements of Kubernaut's API Server Services. All implementation and testing should align with these requirements to ensure high-performance, secure, and scalable API services that enable comprehensive integration and user experience.*
