From 8c27ac3afc9bd086e7724fe6a08b2ab823425b62 Mon Sep 17 00:00:00 2001
From: Gordon <1432970085@qq.com>
Date: Tue, 3 Jan 2023 16:39:27 +0800
Subject: [PATCH] file add

---
 pkg/tools/batcher/batcher.go | 176 +++++++++++++++++++++++++++++++++++
 1 file changed, 176 insertions(+)
 create mode 100644 pkg/tools/batcher/batcher.go

diff --git a/pkg/tools/batcher/batcher.go b/pkg/tools/batcher/batcher.go
new file mode 100644
index 000000000..e6226cd41
--- /dev/null
+++ b/pkg/tools/batcher/batcher.go
@@ -0,0 +1,176 @@
+package batcher
+
+import (
+	"Open_IM/pkg/common/log"
+	"context"
+	"errors"
+	"hash/crc32"
+	"sync"
+	"time"
+)
+
+var (
+	ErrorNotSetFunction = errors.New("not set do function")
+)
+
+var (
+	DefaultSize     = 100
+	DefaultBuffer   = 100
+	DefaultWorker   = 5
+	DefaultInterval = time.Second
+)
+
+type DoFuntion func(ctx context.Context, val map[string][]interface{})
+type Option func(c *Config)
+type Config struct {
+	size     int           //Number of message aggregations
+	buffer   int           //The number of caches running in a single coroutine
+	worker   int           //Number of coroutines processed in parallel
+	interval time.Duration //Time of message aggregations
+}
+
+func newDefaultConfig() *Config {
+	return &Config{
+		size:     DefaultSize,
+		buffer:   DefaultBuffer,
+		worker:   DefaultWorker,
+		interval: DefaultInterval,
+	}
+}
+
+type Batcher struct {
+	config   Config
+	Do       func(ctx context.Context, val map[string][]interface{})
+	Sharding func(key string) int
+	chans    []chan *msg
+	wait     sync.WaitGroup
+}
+type msg struct {
+	key string
+	val interface{}
+}
+
+func NewBatcher(fn DoFuntion, opts ...Option) *Batcher {
+	b := &Batcher{}
+	b.Do = fn
+	config := newDefaultConfig()
+	for _, o := range opts {
+		o(config)
+	}
+	b.chans = make([]chan *msg, b.config.worker)
+	for i := 0; i < b.config.worker; i++ {
+		b.chans[i] = make(chan *msg, b.config.buffer)
+	}
+	return b
+}
+func WithSize(s int) Option {
+	return func(c *Config) {
+		c.size = s
+	}
+}
+
+func WithBuffer(b int) Option {
+	return func(c *Config) {
+		c.buffer = b
+	}
+}
+
+func WithWorker(w int) Option {
+	return func(c *Config) {
+		c.worker = w
+	}
+}
+
+func WithInterval(i time.Duration) Option {
+	return func(c *Config) {
+		c.interval = i
+	}
+}
+func (b *Batcher) Start() error {
+	if b.Do == nil {
+		return ErrorNotSetFunction
+	}
+	if b.Sharding == nil {
+		b.Sharding = func(key string) int {
+			hasCode := int(crc32.ChecksumIEEE([]byte(key)))
+			return hasCode % b.config.worker
+		}
+	}
+	b.wait.Add(len(b.chans))
+	for i, ch := range b.chans {
+		go b.merge(i, ch)
+	}
+	return nil
+}
+
+func (b *Batcher) Add(key string, val interface{}) error {
+	ch, msg := b.add(key, val)
+	select {
+	case ch <- msg:
+	default:
+		return ErrFull
+	}
+	return nil
+}
+
+func (b *Batcher) add(key string, val interface{}) (chan *msg, *msg) {
+	sharding := b.Sharding(key) % b.opts.worker
+	ch := b.chans[sharding]
+	msg := &msg{key: key, val: val}
+	return ch, msg
+}
+
+func (b *Batcher) merge(idx int, ch <-chan *msg) {
+	defer b.wait.Done()
+
+	var (
+		msg        *msg
+		count      int
+		closed     bool
+		lastTicker = true
+		interval   = b.opts.interval
+		vals       = make(map[string][]interface{}, b.opts.size)
+	)
+	if idx > 0 {
+		interval = time.Duration(int64(idx) * (int64(b.opts.interval) / int64(b.opts.worker)))
+	}
+	ticker := time.NewTicker(interval)
+	for {
+		select {
+		case msg = <-ch:
+			if msg == nil {
+				closed = true
+				break
+			}
+			count++
+			vals[msg.key] = append(vals[msg.key], msg.val)
+			if count >= b.opts.size {
+				break
+			}
+			continue
+		case <-ticker.C:
+			if lastTicker {
+				ticker.Stop()
+				ticker = time.NewTicker(b.opts.interval)
+				lastTicker = false
+			}
+		}
+		if len(vals) > 0 {
+			ctx := context.Background()
+			b.Do(ctx, vals)
+			vals = make(map[string][]interface{}, b.opts.size)
+			count = 0
+		}
+		if closed {
+			ticker.Stop()
+			return
+		}
+	}
+}
+
+func (b *Batcher) Close() {
+	for _, ch := range b.chans {
+		ch <- nil
+	}
+	b.wait.Wait()
+}