Kong Gateway Feature-Implementierungen

Detaillierte Implementierung aller Features für Kong Gateway Provider in GAL

Navigation: - ← Zurück zur Kong Übersicht - → Migration & Best Practices

Inhaltsverzeichnis

1. Feature-Implementierungen
2. Kong Feature Coverage
3. Kong-spezifische Details

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Feature-Implementierungen

1. Load Balancing

upstream:
  targets:
    - host: backend-1
      port: 8080
      weight: 100
    - host: backend-2
      port: 8080
      weight: 200
  load_balancer:
    algorithm: round_robin  # round_robin, least_conn, ip_hash

Generiert:

upstreams:
- name: api_service_upstream
  algorithm: round-robin
  targets:
  - target: backend-1:8080
    weight: 100
  - target: backend-2:8080
    weight: 200

2. Health Checks

health_check:
  active:
    enabled: true
    interval: "10s"
    timeout: "5s"
    http_path: "/health"
    healthy_threshold: 2
    unhealthy_threshold: 3

Generiert:

upstreams:
- name: api_service_upstream
  healthchecks:
    active:
      type: http
      http_path: /health
      timeout: 5
      interval: 10
      healthy:
        successes: 2
      unhealthy:
        http_failures: 3

3. Rate Limiting

rate_limit:
  enabled: true
  requests_per_second: 100
  burst: 200

Generiert:

plugins:
- name: rate-limiting
  config:
    second: 100
    policy: local
    hide_client_headers: false

4. Authentication

JWT:

authentication:
  enabled: true
  type: jwt
  jwt:
    issuer: "https://auth.example.com"
    audiences: ["api"]

Generiert:

plugins:
- name: jwt
  config:
    claims_to_verify: [iss, aud]
    key_claim_name: iss

Basic Auth:

authentication:
  enabled: true
  type: basic
  basic_auth:
    users:
      admin: password123

Generiert:

plugins:
- name: basic-auth
consumers:
- username: admin
  basicauth_credentials:
  - username: admin
    password: password123

API Key:

authentication:
  enabled: true
  type: api_key
  api_key:
    key_name: X-API-Key
    in_location: header

Generiert:

plugins:
- name: key-auth
  config:
    key_names: [X-API-Key]

5. CORS

cors:
  enabled: true
  allowed_origins: ["https://app.example.com"]
  allowed_methods: ["GET", "POST", "PUT", "DELETE"]
  allowed_headers: ["Content-Type", "Authorization"]
  allow_credentials: true
  max_age: 86400

Generiert:

plugins:
- name: cors
  config:
    origins: ["https://app.example.com"]
    methods: ["GET", "POST", "PUT", "DELETE"]
    headers: ["Content-Type", "Authorization"]
    credentials: true
    max_age: 86400

6. Timeout & Retry

timeout:
  connect: "10s"
  send: "60s"
  read: "120s"
retry:
  enabled: true
  attempts: 3

Generiert:

services:
- name: api_service
  connect_timeout: 10000    # Milliseconds!
  write_timeout: 60000
  read_timeout: 120000
  retries: 3

Wichtig: Kong verwendet Millisekunden für Timeouts!

7. Request/Response Headers

headers:
  request_add:
    X-Request-ID: "{{uuid}}"
  request_remove:
    - X-Internal-Secret
  response_add:
    X-Gateway: "Kong"
  response_remove:
    - X-Powered-By

Generiert:

plugins:
- name: request-transformer
  config:
    add:
      headers: ["X-Request-ID:{{uuid}}"]
    remove:
      headers: ["X-Internal-Secret"]
- name: response-transformer
  config:
    add:
      headers: ["X-Gateway:Kong"]
    remove:
      headers: ["X-Powered-By"]

8. Body Transformation

body_transformation:
  enabled: true
  request:
    add_fields:
      trace_id: "{{uuid}}"
    remove_fields:
      - secret_key
  response:
    filter_fields:
      - password

Generiert:

plugins:
- name: request-transformer
  config:
    add:
      json: ["trace_id:{{uuid}}"]
    remove:
      json: ["secret_key"]
- name: response-transformer
  config:
    remove:
      json: ["password"]

9. Request Mirroring

✅ Nginx Mirror Module Support (Empfohlen)

Kong basiert auf Nginx/OpenResty, daher können wir das native ngx_http_mirror_module nutzen. Dies ist die empfohlene Methode für Kong OpenSource.

Methode 1: Nginx Mirror Module (via KONG_NGINX_PROXY_INCLUDE) - ⭐ Empfohlen

# GAL Config
routes:
  - path_prefix: /api/users
    mirroring:
      enabled: true
      targets:
        - name: shadow-v2
          upstream:
            host: shadow.example.com
            port: 443
          sample_percentage: 100
          headers:
            X-Mirror: "true"
            X-Shadow-Version: "v2"

Generiert (nginx-template.conf via KONG_NGINX_PROXY_INCLUDE):

# Nginx mirror module configuration
location /api/users {
    mirror /mirror-users;
    mirror_request_body on;
    proxy_pass http://backend-primary:8080;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

location = /mirror-users {
    internal;
    proxy_pass https://shadow.example.com:443/api/users;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Mirror "true";
    proxy_set_header X-Shadow-Version "v2";
}

Hinweise (Nginx Mirror Module): - ✅ Kein Plugin benötigt - Native Nginx-Funktionalität - ✅ OpenSource-kompatibel - Funktioniert mit Kong Gateway (nicht nur Enterprise) - ✅ Asynchronous Mirroring - Blockiert nicht die primäre Response - ✅ Custom Headers - Beliebige Header auf Mirror-Requests - ✅ Production-Ready - Basiert auf battle-tested Nginx mirror module - ⚠️ Sampling - 50% Sampling erfordert split_clients in http block (schwieriger via KONG_NGINX_PROXY_INCLUDE) - ⚠️ Configuration - Erfordert KONG_NGINX_PROXY_INCLUDE Environment Variable

Deployment:

# Docker/Kubernetes Environment Variable
KONG_NGINX_PROXY_INCLUDE: /usr/local/kong/custom/nginx-template.conf

# Mount nginx-template.conf as volume
volumes:
  - ./nginx-template.conf:/usr/local/kong/custom/nginx-template.conf:ro

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Methode 2: Kong Enterprise Plugin (Kong Enterprise only)

plugins:
- name: request-mirror  # Kong Enterprise Plugin
  config:
    mirror_host: https://shadow.example.com:443
    mirror_path: /api/users
    sample_rate: 0.5
    headers:
      X-Mirror: "true"
      X-Shadow-Version: "v2"

Hinweise (Enterprise Plugin): - ⚠️ Enterprise-only - Benötigt Kong Enterprise Lizenz - ✅ Native Plugin - Einfache Konfiguration via Admin API - ✅ Sampling - Native Sample Rate Support (0.0 - 1.0) - ✅ Multiple Targets - Mehrere Shadow-Backends möglich

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Methode 3: Custom Lua Plugin (OpenSource Workaround, nicht empfohlen)

-- handler.lua (Custom Plugin)
local http = require "resty.http"

function RequestMirrorHandler:access(conf)
  if math.random() * 100 <= conf.sample_percentage then
    ngx.timer.at(0, function(premature)
      local httpc = http.new()
      httpc:request_uri(conf.mirror_host .. ngx.var.request_uri, {
        method = ngx.req.get_method(),
        headers = conf.mirror_headers,
      })
      httpc:close()
    end)
  end
end

Hinweise (Custom Lua Plugin): - ⚠️ Nicht empfohlen - Nginx Mirror Module ist besser - ⚠️ Wartungsaufwand - Custom Plugin muss gepflegt werden - ✅ Flexibel - Volle Kontrolle über Mirroring-Logik - ✅ OpenSource - Funktioniert ohne Enterprise-Lizenz

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Empfehlung: 1. Kong OpenSource: Nutze Nginx Mirror Module (Methode 1) ⭐ 2. Kong Enterprise: Nutze request-mirror Plugin (Methode 2) 3. Custom Logic benötigt: Nutze Custom Lua Plugin (Methode 3)

E2E Tests: Siehe tests/test_kong_mirroring_e2e.py für vollständige Beispiele mit Nginx Mirror Module

Docker Setup: Siehe tests/docker/kong-mirroring/ für Docker Compose Konfiguration

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Provider-Vergleich

Kong vs. Andere Provider

Feature	Kong	Envoy	APISIX	Traefik	Nginx	HAProxy
Ease of Use	⭐⭐⭐⭐⭐	⭐⭐	⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐
Plugin Ecosystem	⭐⭐⭐⭐⭐	⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐	⭐⭐	⭐⭐
Admin API	⭐⭐⭐⭐⭐	⭐⭐	⭐⭐⭐⭐⭐	⭐⭐⭐	⭐⭐	⭐⭐
Documentation	⭐⭐⭐⭐⭐	⭐⭐⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐⭐⭐	⭐⭐⭐⭐
Enterprise Support	⭐⭐⭐⭐⭐	⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐

Kong Stärken: - ✅ Einfachste Konfiguration aller Provider - ✅ 300+ Plugins (Community + Enterprise) - ✅ Admin API für dynamische Verwaltung - ✅ Kong Manager (Web UI - Enterprise) - ✅ DB-less Mode (Declarative Config) - ✅ Beste Dokumentation

Kong Schwächen: - ❌ Enterprise Features kostenpflichtig - ⚠️ Performance etwas niedriger als Nginx/HAProxy - ⚠️ Retry keine konditionalen Bedingungen

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Kong Feature Coverage

Detaillierte Analyse basierend auf der offiziellen Kong Dokumentation.

Core Entities (Kong Admin API)

Entity	Import	Export	Status	Bemerkung
services	✅	✅	Voll	Service Definition mit Name/URL
routes	✅	✅	Voll	Path/Host Routing
upstreams	✅	✅	Voll	Load Balancer Configuration
targets	✅	✅	Voll	Backend Endpoints
plugins	✅	✅	Voll	Plugin Configuration
consumers	❌	❌	Nicht	Consumer Management
certificates	❌	❌	Nicht	SSL/TLS Certificates
snis	❌	❌	Nicht	SNI Configuration
ca_certificates	❌	❌	Nicht	CA Certificates

Traffic Control Plugins

Plugin	Import	Export	Status	Bemerkung
rate-limiting	✅	✅	Voll	Rate Limiting (local)
rate-limiting-advanced	❌	❌	Nicht	Enterprise Plugin
request-size-limiting	❌	❌	Nicht	Request Size Limits
response-ratelimiting	❌	❌	Nicht	Response-based Rate Limiting
proxy-cache	❌	❌	Nicht	Caching
proxy-cache-advanced	❌	❌	Nicht	Enterprise Caching

Authentication Plugins

Plugin	Import	Export	Status	Bemerkung
basic-auth	✅	✅	Voll	Basic Authentication
key-auth	✅	✅	Voll	API Key Authentication
jwt	✅	✅	Voll	JWT Validation
oauth2	❌	❌	Nicht	OAuth 2.0
hmac-auth	❌	❌	Nicht	HMAC Signature
ldap-auth	❌	❌	Nicht	LDAP Authentication
openid-connect	❌	❌	Nicht	Enterprise OIDC

Security Plugins

Plugin	Import	Export	Status	Bemerkung
cors	✅	✅	Voll	CORS Policy
acl	❌	❌	Nicht	Access Control Lists
ip-restriction	❌	❌	Nicht	IP Whitelist/Blacklist
bot-detection	❌	❌	Nicht	Bot Detection

Transformation Plugins

Plugin	Import	Export	Status	Bemerkung
request-transformer	⚠️	⚠️	Teilweise	Request Header Transformation
response-transformer	⚠️	⚠️	Teilweise	Response Header Transformation
request-transformer-advanced	❌	❌	Nicht	Enterprise Plugin
response-transformer-advanced	❌	❌	Nicht	Enterprise Plugin

Traffic Management Plugins

Plugin	Import	Export	Status	Bemerkung
canary	❌	❌	Nicht	Canary Releases (Enterprise)
proxy-cache	❌	❌	Nicht	HTTP Caching
upstream-timeout	⚠️	⚠️	Teilweise	Timeout Configuration
http-log	❌	❌	Nicht	HTTP Logging

Load Balancing Features

Feature	Import	Export	Status	Bemerkung
upstreams (round-robin)	✅	✅	Voll	Round Robin (Default)
upstreams (least-connections)	✅	✅	Voll	Least Connections
upstreams (consistent-hashing)	✅	✅	Voll	IP Hash / Cookie Hash
upstreams (latency)	❌	❌	Nicht	Latency-based LB
healthchecks.active	✅	✅	Voll	Active Health Checks
healthchecks.passive	✅	✅	Voll	Passive Health Checks (Circuit Breaker)

Route Matching Features

Feature	Import	Export	Status	Bemerkung
paths (prefix)	✅	✅	Voll	Path Prefix Matching
paths (exact)	❌	❌	Nicht	Exact Path (nur Prefix)
paths (regex)	❌	❌	Nicht	Regex Path Matching
hosts	✅	✅	Voll	Host-based Routing
methods	✅	✅	Voll	HTTP Method Matching
headers	❌	❌	Nicht	Header-based Routing
snis	❌	❌	Nicht	SNI-based Routing

Observability Features

Feature	Import	Export	Status	Bemerkung
Admin API Metrics	N/A	✅	Export	/metrics Endpoint
Prometheus Plugin	❌	❌	Nicht	Prometheus Metrics Export
Datadog Plugin	❌	❌	Nicht	Datadog APM
StatsD Plugin	❌	❌	Nicht	StatsD Metrics
Zipkin Plugin	❌	❌	Nicht	Distributed Tracing
File Log Plugin	❌	❌	Nicht	File-based Logging
Syslog Plugin	❌	❌	Nicht	Syslog Integration

Advanced Features

Feature	Import	Export	Status	Bemerkung
DB-less Mode (Declarative)	✅	✅	Voll	YAML Declarative Config
Admin API (REST)	❌	❌	Nicht	Runtime API nicht in GAL Scope
Kong Manager (UI)	N/A	N/A	N/A	Enterprise Feature
Dev Portal	N/A	N/A	N/A	Enterprise Feature
Service Mesh (Kuma)	❌	❌	Nicht	Service Mesh Integration
Serverless Functions	❌	❌	Nicht	Pre/Post Function Plugins
Custom Plugins (Lua)	❌	❌	Nicht	Custom Lua Plugins

Coverage Score nach Kategorie

Kategorie	Features Total	Unterstützt	Coverage
Core Entities	9	5 voll	55%
Traffic Control	6	1 voll	17%
Authentication	7	3 voll	43%
Security	4	1 voll	25%
Transformation	4	0 voll, 2 teilweise	25%
Traffic Management	4	0 voll, 1 teilweise	12%
Load Balancing	6	4 voll	67%
Route Matching	7	3 voll	43%
Observability	7	1 export	14%
Advanced	6	1 voll	17%

Gesamt (API Gateway relevante Features): ~38% Coverage

Import Coverage: ~60% (Import bestehender Kong Configs → GAL) Export Coverage: ~85% (GAL → Kong Declarative Config)

Bidirektionale Feature-Unterstützung

Vollständig bidirektional (Import ↔ Export): 1. ✅ Services (Name, URL, Protocol) 2. ✅ Routes (Paths, Hosts, Methods) 3. ✅ Upstreams (Targets, Load Balancing) 4. ✅ Health Checks (Active + Passive) 5. ✅ Load Balancing (Round Robin, Least Connections, Consistent Hashing) 6. ✅ Rate Limiting (rate-limiting plugin) 7. ✅ Authentication (Basic, API Key, JWT) 8. ✅ CORS (cors plugin)

Nur Export (GAL → Kong): 9. ⚠️ Request/Response Headers (request-transformer plugin) 10. ⚠️ Timeouts (Service-level timeouts)

Features mit Einschränkungen: - Enterprise Plugins: Nicht in Kong OSS (rate-limiting-advanced, canary, openid-connect) - Exact Path Matching: Kong unterstützt nur Prefix (paths array) - Regex/Header Routing: Nicht in GAL Scope - Custom Lua Plugins: Nicht parsebar/generierbar

Import-Beispiel (Kong → GAL)

Input (kong.yaml - Declarative Config):

_format_version: "3.0"

services:
- name: api_service
  url: http://backend.svc:8080
  routes:
  - name: api_route
    paths:
    - /api
    methods:
    - GET
    - POST

upstreams:
- name: api_upstream
  algorithm: round-robin
  targets:
  - target: backend-1.svc:8080
    weight: 100
  - target: backend-2.svc:8080
    weight: 100
  healthchecks:
    active:
      healthy:
        interval: 10
        successes: 2
      unhealthy:
        interval: 10
        http_failures: 3

plugins:
- name: rate-limiting
  config:
    minute: 100
    policy: local
- name: jwt
  config:
    claims_to_verify:
    - exp

Output (gal-config.yaml):

version: "1.0"
provider: kong
global:
  host: 0.0.0.0
  port: 8000
services:
  - name: api_service
    type: rest
    protocol: http
    upstream:
      targets:
        - host: backend-1.svc
          port: 8080
          weight: 100
        - host: backend-2.svc
          port: 8080
          weight: 100
      load_balancer:
        algorithm: round_robin
      health_check:
        active:
          enabled: true
          interval: "10s"
          healthy_threshold: 2
          unhealthy_threshold: 3
    routes:
      - path_prefix: /api
        methods:
          - GET
          - POST
        rate_limit:
          enabled: true
          requests_per_second: 1.67  # 100/minute
        authentication:
          enabled: true
          type: jwt

Empfehlungen für zukünftige Erweiterungen

Priorität 1 (High Impact): 1. Request/Response Transformation - Vollständige body transformation support 2. Prometheus Plugin - Metrics Export Integration 3. IP Restriction - Whitelist/Blacklist Support 4. Request Size Limiting - request-size-limiting Plugin 5. Exact Path Matching - Zusätzlich zu Prefix

Priorität 2 (Medium Impact): 6. Proxy Cache - HTTP Caching Support 7. File/Syslog Logging - Zusätzliche Logging Backends 8. OAuth2 Plugin - OAuth 2.0 Support 9. ACL Plugin - Access Control Lists 10. Bot Detection - Bot Detection Plugin

Priorität 3 (Nice to Have): 11. HMAC Auth - HMAC Signature Authentication 12. LDAP Auth - LDAP Integration 13. Header/Query Routing - Advanced Routing 14. Custom Lua Plugins - Plugin Generation 15. Zipkin/Datadog Integration - Tracing/Metrics

Test Coverage (Import)

Kong Import Tests: 21 Tests (test_import_kong.py)

Test Kategorie	Tests	Status
Basic Import	3	✅ Passing
Services & Routes	3	✅ Passing
Upstreams & Load Balancing	3	✅ Passing
Health Checks	2	✅ Passing
Rate Limiting	2	✅ Passing
Authentication (Basic, JWT, API Key)	3	✅ Passing
CORS	1	✅ Passing
Headers	1	✅ Passing
Errors & Warnings	3	✅ Passing

Coverage Verbesserung durch Import: 8% → 42% (+34%)

Roundtrip-Kompatibilität

Szenario	Roundtrip	Bemerkung
Basic Service + Route	✅ 100%	Perfekt
Upstreams + Load Balancing	✅ 100%	Perfekt
Health Checks (Active + Passive)	✅ 95%	Minimal Details verloren
Rate Limiting	✅ 100%	Perfekt
Authentication (Basic, JWT, API Key)	✅ 100%	Perfekt
CORS	✅ 100%	Perfekt
Request/Response Headers	✅ 90%	request-transformer Einschränkungen
Combined Features	✅ 95%	Sehr gut

Durchschnittliche Roundtrip-Kompatibilität: ~97%

Fazit

Kong Import Coverage: - ✅ Core Features: 90% Coverage (Services, Routes, Upstreams, Plugins) - ⚠️ Advanced Plugins: 30% Coverage (viele Community Plugins nicht unterstützt) - ❌ Enterprise Features: Nicht unterstützt (canary, openid-connect, rate-limiting-advanced)

Kong Export Coverage: - ✅ Core Features: 95% Coverage (alle GAL Features → Kong) - ✅ Best Practices: Eingebaut (Health Checks, Load Balancing) - ✅ DB-less Mode: Vollständig unterstützt (Declarative YAML)

Empfehlung: - 🚀 Für Standard API Gateway Workloads: Perfekt geeignet - ✅ Für Kong → GAL Migration: 95% automatisiert, 5% Review - ⚠️ Für komplexe Plugin-Setups: Manuelle Nachbearbeitung nötig - ❌ Für Enterprise Features: Nicht unterstützt (Kong Enterprise erforderlich)

Referenzen: - 📚 Kong Plugin Hub - 📚 Kong Admin API - 📚 Kong Declarative Config - 📚 Kong Load Balancing

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Kong-spezifische Details

Plugin-Architektur

Kong's Macht liegt in seinen Plugins:

Plugin Execution Order: 1. Pre-Function (Custom Lua before request) 2. Authentication (JWT, Basic, API Key, etc.) 3. Rate Limiting (Rate limits enforcement) 4. Request Transformer (Modify request) 5. Proxy (Forward to upstream) 6. Response Transformer (Modify response) 7. Post-Function (Custom Lua after response)

Admin API

Kong bietet eine REST API für Verwaltung:

# Services auflisten
curl http://localhost:8001/services

# Service erstellen
curl -X POST http://localhost:8001/services \
  -d "name=my-service" \
  -d "url=http://backend:8080"

# Route hinzufügen
curl -X POST http://localhost:8001/services/my-service/routes \
  -d "paths[]=/api"

# Plugin aktivieren
curl -X POST http://localhost:8001/services/my-service/plugins \
  -d "name=rate-limiting" \
  -d "config.second=100"

Hinweis: GAL generiert Declarative Config (DB-less Mode), nicht Admin API Calls.

DB-less vs. DB Mode

DB-less Mode (Empfohlen für GAL): - ✅ Keine Datenbank erforderlich - ✅ Einfaches Deployment - ✅ Git-freundlich (YAML-Config) - ❌ Keine dynamischen Änderungen via Admin API

DB Mode (PostgreSQL): - ✅ Dynamische Änderungen via Admin API - ✅ Kong Manager UI - ❌ Benötigt Datenbank - ❌ Komplexeres Setup

Kong Manager (Enterprise)

Kong Enterprise bietet eine Web UI:

# Kong Manager aktivieren (Enterprise)
docker run -d \
  --name kong-enterprise \
  -e "KONG_ADMIN_GUI_URL=http://localhost:8002" \
  kong/kong-gateway:3.4-enterprise

Zugriff: http://localhost:8002

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