API Gateway

English

中文

English

中文

Appearance

TODO List - API Gateway Feature Development Plan ​

This document lists the missing features and development plan for API Gateway. These features are based on research and analysis of industry-standard API Gateways (such as Kong, Traefik, Envoy).

High Priority (Core Features) ​

1. Load Balancing ​

Status: 🟢 Implemented
Description: Currently only supports a single backend service instance. Multi-instance load balancing is needed.

Requirements:

  • [x] Multi-backend instance configuration (upstream/backend pool)
  • [x] Load balancing algorithms (round-robin, least-connections, ip-hash, weighted)
  • [x] Health check-driven dynamic routing (automatically remove unhealthy instances)
  • [x] Weight configuration support

Impact: Cannot achieve high availability and horizontal scaling

2. Rate Limiting & Throttling ​

Status: 🟢 Implemented
Description: Rate limiting plugin is fully implemented with support for multiple algorithms and key types (backed by Application.Cache()).

Requirements:

  • [x] Rate limiting based on IP, user, API Key
  • [x] Token bucket/leaky bucket algorithm implementation
  • [x] Distributed rate limiting (based on Redis)
  • [x] Rate limiting policy configuration (requests per second, requests per minute, etc.)
  • [x] Rate limit response (429 Too Many Requests)
  • [x] Rate limiting plugin implementation

Impact: Cannot prevent API abuse and DDoS attacks

3. Timeout Control ​

Status: 🟡 Partially Implemented (health check has timeout, but request proxy layer is missing)
Description: Health check has timeout configuration, but request proxy layer lacks timeout control.

Requirements:

  • [ ] Connection timeout (connect timeout)
  • [ ] Read timeout
  • [ ] Write timeout
  • [ ] Global and route-level timeout configuration

Impact: Cannot prevent slow requests from blocking, may cause resource exhaustion

4. Retry Mechanism ​

Status: 🔴 Not Implemented
Description: Retry functionality is completely missing.

Requirements:

  • [ ] Configurable retry count
  • [ ] Retry strategies (exponential backoff, fixed interval)
  • [ ] Retryable error code configuration (5xx, network errors, etc.)
  • [ ] Idempotency check

Impact: Cannot automatically recover from network jitter, affects availability

5. Monitoring & Observability ​

Status: 🔴 Not Implemented
Description: Only basic logging, lacks structured monitoring.

Requirements:

  • [ ] Prometheus metrics export
  • [ ] Request/response metrics (QPS, latency, error rate)
  • [ ] Distributed tracing (OpenTelemetry/Jaeger integration)
  • [ ] Structured logging (JSON format)
  • [ ] Alert integration

Impact: Cannot monitor gateway performance, difficult to diagnose issues

Medium Priority (Important Features) ​

6. Circuit Breaker ​

Status: 🔴 Not Implemented
Description: Circuit breaker functionality is completely missing.

Requirements:

  • [ ] Error rate-based circuit breaking
  • [ ] Response time-based circuit breaking
  • [ ] Half-open state automatic recovery
  • [ ] Circuit breaker status monitoring

Impact: Cannot prevent cascading failures, cannot fail fast

7. CORS Support ​

Status: 🔴 Not Implemented
Description: CORS functionality is completely missing.

Requirements:

  • [ ] CORS preflight request (OPTIONS) handling
  • [ ] Configurable CORS policies (allowed origins, methods, headers, credentials, etc.)
  • [ ] Route-level CORS configuration

Impact: Browser cross-origin requests cannot work properly

8. Authentication/Authorization Implementation ​

Status: 🟡 Partially Implemented (configuration exists but implementation may be incomplete)
Description: Configuration level supports various authentication types, but actual implementation may be incomplete.

Requirements:

  • [ ] JWT verification and parsing
  • [ ] OAuth2/OIDC complete flow implementation
  • [ ] API Key verification
  • [ ] Role-based access control (RBAC)
  • [ ] Permission policy configuration

Impact: Security features incomplete, security risks exist

9. Request Validation ​

Status: 🔴 Not Implemented
Description: Request validation functionality is completely missing.

Requirements:

  • [ ] Request size limits
  • [ ] Request parameter validation
  • [ ] Schema validation (JSON Schema)
  • [ ] Request signature verification

Impact: Cannot prevent malicious requests and invalid data

10. Response Caching ​

Status: 🟡 Partially Implemented (Redis configuration exists but caching functionality not implemented)
Description: Redis cache configuration exists, but response caching functionality is not implemented.

Requirements:

  • [ ] Path-based response caching
  • [ ] Cache policy configuration (TTL, cache key rules)
  • [ ] Cache invalidation strategy
  • [ ] Conditional request support (ETag, Last-Modified)

Impact: Cannot reduce backend load, affects performance

Low Priority (Enhancement Features) ​

11. WebSocket Support ​

Status: 🟡 Partially Implemented (dependency exists but not integrated)
Description: Although gorilla/websocket dependency exists in go.mod, WebSocket proxy is not implemented in core code.

Requirements:

  • [ ] WebSocket upgrade handling
  • [ ] WebSocket connection proxying
  • [ ] WebSocket message forwarding

Impact: Cannot support real-time communication scenarios

12. SSL/TLS Termination ​

Status: 🟡 Partially Implemented (configuration exists but not implemented)
Description: Configuration structure exists, but not implemented in core code.

Requirements:

  • [ ] TLS certificate management
  • [ ] SNI (Server Name Indication) support
  • [ ] Automatic certificate renewal (Let's Encrypt integration)
  • [ ] TLS version and cipher suite configuration

Impact: Cannot terminate TLS at gateway level, increases backend service burden

13. Service Discovery Integration ​

Status: 🔴 Not Implemented
Description: Only supports static configuration, does not support dynamic service discovery.

Requirements:

  • [ ] Kubernetes Service discovery
  • [ ] Consul integration
  • [ ] etcd integration
  • [ ] DNS service discovery
  • [ ] Dynamic backend registration/deregistration

Impact: Cannot adapt to cloud-native environments, complex configuration management

14. Canary Deployment ​

Status: 🔴 Not Implemented
Description: Canary deployment functionality is completely missing.

Requirements:

  • [ ] Weight-based traffic distribution
  • [ ] Header-based routing rules
  • [ ] A/B testing support
  • [ ] Version management

Impact: Cannot safely perform version upgrades and testing

15. Request/Response Body Transformation ​

Status: 🔴 Not Implemented
Description: Only supports header and query parameter modification, does not support request/response body transformation.

Requirements:

  • [ ] JSON request body modification
  • [ ] XML request body transformation
  • [ ] Request/response body size limits
  • [ ] Content type transformation

Impact: Cannot achieve complex protocol conversion and data transformation

16. API Versioning ​

Status: 🟡 Partially Implemented (path level)
Description: Path-level version control, lacks structured version management.

Requirements:

  • [ ] API version definition and management
  • [ ] Version routing rules
  • [ ] Version deprecation strategy
  • [ ] Version compatibility checking

Impact: Difficult API evolution management

17. Request Logging ​

Status: 🟡 Partially Implemented (basic logging)
Description: Only basic logging, lacks structured request logging.

Requirements:

  • [ ] Access log format
  • [ ] Request/response logging
  • [ ] Log sampling
  • [ ] Sensitive information masking

Impact: Difficult auditing and troubleshooting

18. Multi-Protocol Support ​

Status: 🟡 Partially Implemented (HTTP/HTTPS only)
Description: Only supports HTTP/HTTPS.

Requirements:

  • [ ] gRPC proxy
  • [ ] GraphQL support
  • [ ] Complete HTTP/2 support
  • [ ] WebSocket (already mentioned)

Impact: Cannot support modern microservices architecture

Implementation Recommendations ​

  1. Leverage Existing Plugin System: Some features can be implemented as plugins (e.g., rate limiting, CORS) to keep the core lightweight
  2. Incremental Implementation: Prioritize high-priority features, gradually improve
  3. Reference Industry Standards: Reference implementation approaches from Kong, Traefik, Envoy
  4. Maintain Backward Compatibility: New features should not break existing configuration and API

Status Legend ​

  • 🔴 Not Implemented - Feature completely missing
  • 🟡 Partially Implemented - Related configuration or dependencies exist, but feature is incomplete
  • 🟢 Implemented - Feature is complete and usable

Changelog ​

  • 2024-12-01: Initial TODO List created, based on feature analysis
  • 2026-02-01: Load Balancing feature implemented (round-robin, weighted, least-connections, ip-hash algorithms, health checks, multi-server support)

Released under the MIT License.

Copyright © 2024 GoZoox Team