Envoy XDS协议学习

Envoy xds学习

资料地址

1. envoy官网资料连接

接口说明

1. xds分为增量接口和全量接口
2. SotW：state of the world 即全量的数据
3. Incremental： 增量的数据

具体接口

• Listener: Listener Discovery Service (LDS)
  SotW: ListenerDiscoveryService.StreamListeners
  Incremental: ListenerDiscoveryService.DeltaListeners
• RouteConfiguration: Route Discovery Service (RDS)
  SotW: RouteDiscoveryService.StreamRoutes
  Incremental: RouteDiscoveryService.DeltaRoutes
• ScopedRouteConfiguration: Scoped Route Discovery Service (SRDS)
  SotW: ScopedRouteDiscoveryService.StreamScopedRoutes
  Incremental: ScopedRouteDiscoveryService.DeltaScopedRoutes
• VirtualHost: Virtual Host Discovery Service (VHDS)
  SotW: N/A
  Incremental: VirtualHostDiscoveryService.DeltaVirtualHosts
• Cluster: Cluster Discovery Service (CDS)
  SotW: ClusterDiscoveryService.StreamClusters
  Incremental: ClusterDiscoveryService.DeltaClusters
• ClusterLoadAssignment: Endpoint Discovery Service (EDS)
  SotW: EndpointDiscoveryService.StreamEndpoints
  Incremental: EndpointDiscoveryService.DeltaEndpoints
  Secret: Secret Discovery Service (SDS)
  SotW: SecretDiscoveryService.StreamSecrets
  Incremental: SecretDiscoveryService.DeltaSecrets
• Runtime: Runtime Discovery Service (RTDS)
  SotW: RuntimeDiscoveryService.StreamRuntime
  Incremental: RuntimeDiscoveryService.DeltaRuntime
• ADS: 聚集接口，所有资源都使用一个接口
  SotW: AggregatedDiscoveryService.StreamAggregatedResources
  Incremental: AggregatedDiscoveryService.DeltaAggregatedResources

接口配置说明

1. ApiConfigSource
2. ConfigSource

ACK和NACK

1. ACK
   
2. NACK
   

接口发送

1. SotW场景
   • 客户端发送resource_names为空，则服务端理解为订阅*
   • 客户端发送resource_names为和A，则服务端理解为继续订阅并新加一个A
   • 客户端发送resource_names为A，则服务端理解为取消订阅*，并继续订阅A
   • 客户端发送resource_names为空，则取消订阅A
2. 增量场景
   • 客户端发送resource_names_subscribe为空，则服务端理解为订阅*
   • 客户端发送resource_names_subscribe为A，则继续订阅*和新加A
   • 客户端发送resource_names_unsubscribe为*，则取消订阅*，继续订阅A
   • 客户端发送resource_names_unsubscribe为A，则取消订阅A

网关路由一致性

1. envoy是最终一致性的