github.com/matrixorigin/matrixone@v1.2.0/pkg/vm/engine/tae/logtail/service/event.go (about) 1 // Copyright 2021 Matrix Origin 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package service 16 17 import ( 18 "context" 19 20 "github.com/matrixorigin/matrixone/pkg/pb/logtail" 21 "github.com/matrixorigin/matrixone/pkg/pb/timestamp" 22 ) 23 24 const ( 25 // FIXME: do we need to make event buffer size configurable? 26 eventBufferSize = 6 * 1024 27 ) 28 29 // Notifier provides incremental logtail. 30 type Notifier struct { 31 ctx context.Context 32 C chan event 33 } 34 35 func NewNotifier(ctx context.Context, buffer int) *Notifier { 36 return &Notifier{ 37 ctx: ctx, 38 C: make(chan event, buffer), 39 } 40 } 41 42 // NotifyLogtail provides incremental logtail. 43 func (n *Notifier) NotifyLogtail( 44 from, to timestamp.Timestamp, closeCB func(), tails ...logtail.TableLogtail, 45 ) error { 46 select { 47 case <-n.ctx.Done(): 48 return n.ctx.Err() 49 case n.C <- event{from: from, to: to, closeCB: closeCB, logtails: tails}: 50 } 51 return nil 52 } 53 54 type event struct { 55 from, to timestamp.Timestamp 56 closeCB func() 57 logtails []logtail.TableLogtail 58 }