| // Copyright Istio Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package memory |
| |
| import ( |
| "istio.io/pkg/log" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-go-pixiu/pilot/pkg/model" |
| config2 "github.com/apache/dubbo-go-pixiu/pkg/config" |
| ) |
| |
| const ( |
| // BufferSize specifies the buffer size of event channel |
| BufferSize = 100 |
| ) |
| |
| // Handler specifies a function to apply on a Config for a given event type |
| type Handler func(config2.Config, config2.Config, model.Event) |
| |
| // Monitor provides methods of manipulating changes in the config store |
| type Monitor interface { |
| Run(<-chan struct{}) |
| AppendEventHandler(config2.GroupVersionKind, Handler) |
| ScheduleProcessEvent(ConfigEvent) |
| } |
| |
| // ConfigEvent defines the event to be processed |
| type ConfigEvent struct { |
| config config2.Config |
| old config2.Config |
| event model.Event |
| } |
| |
| type configStoreMonitor struct { |
| store model.ConfigStore |
| handlers map[config2.GroupVersionKind][]Handler |
| eventCh chan ConfigEvent |
| // If enabled, events will be handled synchronously |
| sync bool |
| } |
| |
| // NewMonitor returns new Monitor implementation with a default event buffer size. |
| func NewMonitor(store model.ConfigStore) Monitor { |
| return newBufferedMonitor(store, BufferSize, false) |
| } |
| |
| // NewMonitor returns new Monitor implementation which will process events synchronously |
| func NewSyncMonitor(store model.ConfigStore) Monitor { |
| return newBufferedMonitor(store, BufferSize, true) |
| } |
| |
| // NewBufferedMonitor returns new Monitor implementation with the specified event buffer size |
| func newBufferedMonitor(store model.ConfigStore, bufferSize int, sync bool) Monitor { |
| handlers := make(map[config2.GroupVersionKind][]Handler) |
| |
| for _, s := range store.Schemas().All() { |
| handlers[s.Resource().GroupVersionKind()] = make([]Handler, 0) |
| } |
| |
| return &configStoreMonitor{ |
| store: store, |
| handlers: handlers, |
| eventCh: make(chan ConfigEvent, bufferSize), |
| sync: sync, |
| } |
| } |
| |
| func (m *configStoreMonitor) ScheduleProcessEvent(configEvent ConfigEvent) { |
| if m.sync { |
| m.processConfigEvent(configEvent) |
| } else { |
| m.eventCh <- configEvent |
| } |
| } |
| |
| func (m *configStoreMonitor) Run(stop <-chan struct{}) { |
| if m.sync { |
| <-stop |
| return |
| } |
| for { |
| select { |
| case <-stop: |
| return |
| case ce, ok := <-m.eventCh: |
| if ok { |
| m.processConfigEvent(ce) |
| } |
| } |
| } |
| } |
| |
| func (m *configStoreMonitor) processConfigEvent(ce ConfigEvent) { |
| if _, exists := m.handlers[ce.config.GroupVersionKind]; !exists { |
| log.Warnf("Config GroupVersionKind %s does not exist in config store", ce.config.GroupVersionKind) |
| return |
| } |
| m.applyHandlers(ce.old, ce.config, ce.event) |
| } |
| |
| func (m *configStoreMonitor) AppendEventHandler(typ config2.GroupVersionKind, h Handler) { |
| m.handlers[typ] = append(m.handlers[typ], h) |
| } |
| |
| func (m *configStoreMonitor) applyHandlers(old config2.Config, config config2.Config, e model.Event) { |
| for _, f := range m.handlers[config.GroupVersionKind] { |
| f(old, config, e) |
| } |
| } |