tasks/common/stream_batcher/batcher_test.go

// The MIT License
//
// Copyright (c) 2024 Temporal Technologies Inc.  All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package stream_batcher

import (
	"context"
	"math/rand"
	"runtime"
	"sync"
	"sync/atomic"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"go.temporal.io/server/common/clock"
)

// this test uses time.Sleep to allow goroutines to get into a blocked state
//
//nolint:forbidigo
func TestStreamBatcher_MinDelay(t *testing.T) {
	clk := clock.NewEventTimeSource()

	opts := BatcherOptions{
		MaxItems: 10,
		MinDelay: 100 * time.Millisecond,
		MaxDelay: 400 * time.Millisecond,
		IdleTime: 1000 * time.Millisecond,
	}
	process := func(items []int) (total int) {
		for _, i := range items {
			total += i
		}
		clk.Sleep(50 * time.Millisecond)
		return
	}
	sb := NewBatcher(process, opts, clk)

	var wg sync.WaitGroup
	wg.Add(3)

	// 350 = 200 (last Add call) + 100 (MinDelay) + 50 (process time)
	targetMS := int64(350)

	go func() {
		defer wg.Done()
		clk.Sleep(100 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 100)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()
	go func() {
		defer wg.Done()
		clk.Sleep(150 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 20)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()
	go func() {
		defer wg.Done()
		clk.Sleep(200 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 3)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()

	time.Sleep(time.Millisecond) // wait for goroutines to get into Add
	clk.AdvanceNext()            // first Add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // second Add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // third add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // min delay
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // process time

	wg.Wait()
}

// this test uses time.Sleep to allow goroutines to get into a blocked state
//
//nolint:forbidigo
func TestStreamBatcher_MaxDelay(t *testing.T) {
	clk := clock.NewEventTimeSource()

	opts := BatcherOptions{
		MaxItems: 10,
		MinDelay: 100 * time.Millisecond,
		MaxDelay: 120 * time.Millisecond,
		IdleTime: 1000 * time.Millisecond,
	}
	process := func(items []int) (total int) {
		for _, i := range items {
			total += i
		}
		clk.Sleep(50 * time.Millisecond)
		return
	}
	sb := NewBatcher(process, opts, clk)

	var wg sync.WaitGroup
	wg.Add(4)

	// 270 = 220 (first Add call + max delay) + 50 (process time)
	targetMS := int64(270)

	go func() {
		defer wg.Done()
		clk.Sleep(100 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 100)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()
	go func() {
		defer wg.Done()
		clk.Sleep(150 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 20)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()
	go func() {
		defer wg.Done()
		clk.Sleep(200 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 3)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()
	go func() {
		defer wg.Done()
		clk.Sleep(250 * time.Millisecond)
		ctx := context.Background()
		// misses the first batch, will be in separate batch
		total, err := sb.Add(ctx, 777)
		assert.NoError(t, err)
		assert.Equal(t, 777, total)
		// end of first process time + 100 (min delay) + 50 (second process time)
		assert.Equal(t, targetMS+100+50, clk.Now().UnixMilli())
	}()

	time.Sleep(time.Millisecond) // wait for goroutines to get into Add
	clk.AdvanceNext()            // first Add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // second Add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // third add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // max delay
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // process time
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // fourth add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // min delay
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // process time

	wg.Wait()
}

// this test uses time.Sleep to allow goroutines to get into a blocked state
//
//nolint:forbidigo
func TestStreamBatcher_MaxItems(t *testing.T) {
	clk := clock.NewEventTimeSource()

	opts := BatcherOptions{
		MaxItems: 2,
		MinDelay: 100 * time.Millisecond,
		MaxDelay: 400 * time.Millisecond,
		IdleTime: 1000 * time.Millisecond,
	}
	process := func(items []int) (total int) {
		for _, i := range items {
			total += i
		}
		clk.Sleep(50 * time.Millisecond)
		return
	}
	sb := NewBatcher(process, opts, clk)

	var wg sync.WaitGroup
	wg.Add(2)

	// 200 = 150 (second Add call) + 50 (process time)
	targetMS := int64(200)

	go func() {
		defer wg.Done()
		clk.Sleep(100 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 100)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()
	go func() {
		defer wg.Done()
		clk.Sleep(150 * time.Millisecond)
		ctx := context.Background()
		total, err := sb.Add(ctx, 23)
		assert.NoError(t, err)
		assert.Equal(t, 123, total)
		assert.Equal(t, targetMS, clk.Now().UnixMilli())
	}()

	time.Sleep(time.Millisecond) // wait for goroutines to get into Add
	clk.AdvanceNext()            // first Add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // second Add
	time.Sleep(time.Millisecond)
	clk.AdvanceNext() // process time

	wg.Wait()
}

func TestStreamBatcher_Random(t *testing.T) {
	// throw a lot of concurrent calls at the batcher and make sure there are no errors at
	// least. with log statements in stream_batcher.go, you can see this does (or did at some
	// point) exercise all of the tricky spots.

	clk := clock.NewEventTimeSource()

	const workers = 20
	const events = 1000

	opts := BatcherOptions{
		MaxItems: 10,
		MinDelay: 100 * time.Millisecond,
		MaxDelay: 400 * time.Millisecond,
		IdleTime: 100 * time.Millisecond,
	}
	process := func(items []int) (total int) {
		for _, i := range items {
			total += i
		}
		clk.Sleep(time.Duration(rand.Intn(50)) * time.Millisecond)
		return
	}
	sb := NewBatcher(process, opts, clk)

	var running atomic.Int64
	for range workers {
		running.Add(1)
		go func() {
			ctx := context.Background()
			for range events {
				_, err := sb.Add(ctx, 1)
				assert.NoError(t, err)
				clk.Sleep(time.Duration(rand.Intn(1000)) * time.Millisecond)
			}
			running.Add(-1)
		}()
	}

	for running.Load() > 0 {
		clk.AdvanceNext()
		// What we'd really like is a way to say "wait until all of these goroutines are
		// blocked on a timer". But that's not quite possible with the Go runtime. Running
		// Gosched repeatedly is good enough for this test.
		for range workers + 1 {
			runtime.Gosched()
		}
	}
}