worker_test.go

package goneric

import (
	"fmt"
	"github.com/stretchr/testify/assert"
	"sort"
	"strconv"
	"testing"
	"time"
)

func TestWorkerPool(t *testing.T) {
	t.Run("chan open", func(t *testing.T) {

		in := make(chan int, 1)
		out := make(chan string, 2)
		go func() {
			for i := 0; i < 32; i++ {
				in <- i
			}
			close(in)
		}()
		go func() {
			WorkerPool(in, out, func(i int) string {
				return strconv.Itoa(i)
			}, 4, true)
		}()

		outSlice := []string{}
		for o := range out {
			outSlice = append(outSlice, o)
		}
		assert.True(t, CompareSliceSet(
			[]string{"0", "1", "2", "4", "5", "6", "7", "3", "8", "9", "10", "11", "12", "13", "16", "14", "17", "18", "19", "15", "20", "21", "22", "25", "26", "27", "28", "23", "24", "29", "30", "31"},
			outSlice))
		assert.Panics(t, func() {
			WorkerPool(in, out, func(i int) string {
				return strconv.Itoa(i)
			}, 0)
		})

	})
	t.Run("chan closed", func(t *testing.T) {

		in := make(chan int, 1)
		go func() {
			for i := 0; i < 32; i++ {
				in <- i
			}
			close(in)
		}()
		out := WorkerPoolBackground(in, func(i int) string {
			return strconv.Itoa(i)
		}, 4)

		outSlice := ChanToSliceN(out, 32)
		assert.True(t, CompareSliceSet(
			[]string{"0", "1", "2", "4", "5", "6", "7", "3", "8", "9", "10", "11", "12", "13", "16", "14", "17", "18", "19", "15", "20", "21", "22", "25", "26", "27", "28", "23", "24", "29", "30", "31"},
			outSlice))
		assert.Panics(t, func() {
			WorkerPoolBackground(in, func(i int) string {
				return strconv.Itoa(i)
			}, 0)
		})

	})
}

func TestWorkerPoolBackground(t *testing.T) {
	in := make(chan int, 1)
	go func() {
		for i := 0; i < 32; i++ {
			in <- i
		}
		close(in)
	}()
	out := WorkerPoolBackground(in, func(i int) string {
		return strconv.Itoa(i)
	}, 4, true)

	outSlice := ChanToSlice(out)
	assert.True(t, CompareSliceSet(
		[]string{"0", "1", "2", "4", "5", "6", "7", "3", "8", "9", "10", "11", "12", "13", "16", "14", "17", "18", "19", "15", "20", "21", "22", "25", "26", "27", "28", "23", "24", "29", "30", "31"},
		outSlice))
	assert.Panics(t, func() {
		WorkerPoolBackground(in, func(i int) string {
			return strconv.Itoa(i)
		}, 0, true)
	})

}

func TestWorkerPoolFinisher(t *testing.T) {
	in := make(chan int, 1)
	out := make(chan string, 2)
	go func() {
		for i := 0; i < 32; i++ {
			in <- i
		}
		close(in)
	}()
	finisher := WorkerPoolFinisher(in, out, func(i int) string {
		return strconv.Itoa(i)
	}, 4)

	outSlice := []string{}
	for o := range out {
		outSlice = append(outSlice, o)
	}
	assert.True(t, CompareSliceSet(
		[]string{"0", "1", "2", "4", "5", "6", "7", "3", "8", "9", "10", "11", "12", "13", "16", "14", "17", "18", "19", "15", "20", "21", "22", "25", "26", "27", "28", "23", "24", "29", "30", "31"},
		outSlice))
	assert.True(t, <-finisher)
	assert.Panics(t, func() {
		WorkerPool(in, out, func(i int) string {
			return strconv.Itoa(i)
		}, 0)
	})
	assert.Panics(t, func() { close(out) })
}

func TestWorkerPoolDrain(t *testing.T) {
	c := make(chan func(), 1)
	end := make(chan bool, 1)
	finish := WorkerPoolDrain(func(f func()) { f() }, 4, c)
	var a1, a2 int
	c <- func() { a1 = 1 }
	c <- func() { a2 = 2 }
	c <- func() { end <- true }
	close(c)
	<-finish
	time.Sleep(time.Millisecond * 10)
	assert.True(t, <-end)
	assert.Equal(t, 1, a1)
	assert.Equal(t, 2, a2)
}

func TestWorkerPoolAsync(t *testing.T) {
	async, finish := WorkerPoolAsync(func(i int) string { return strconv.Itoa(i) }, 2)
	a1 := async(1)
	a2 := async(2)
	a3 := async(3)
	a4 := async(4)
	finish()
	assert.Equal(t, "1", <-a1)
	assert.Equal(t, "2", <-a2)
	assert.Equal(t, "3", <-a3)
	assert.Equal(t, "4", <-a4)

}

func ExampleWorkerPoolAsync() {
	// make our worker with function to mangle data
	async, finish := WorkerPoolAsync(
		func(i int) string { return strconv.Itoa(i) },
		2)
	defer finish() // close the pool once we stop using it
	// queue some jobs
	job1 := async(1)
	job2 := async(2)
	job3 := async(3)
	job4 := async(4)
	// all of those jobs are running in background at this point
	// now get results
	fmt.Printf("%s %s %s %s",
		<-job1,
		<-job3,
		<-job2,
		<-job4,
	)
	//Output: 1 3 2 4
}

func ExampleWorkerPoolBackground() {
	out :=
		WorkerPoolBackground(
			WorkerPoolBackground(
				WorkerPoolBackground(
					GenChanN(func(idx int) int { return idx + 1 }, 3, true),
					func(i int) string { return strconv.Itoa(i) },
					4, true),
				func(s string) string { return ">" + s },
				5, true,
			),
			func(s string) string { return " |" + s },
			6, true)
	sliceOut := ChanToSlice(out)
	sort.Slice(sliceOut, func(i, j int) bool { return sliceOut[i] < sliceOut[j] })
	fmt.Printf("%v", sliceOut)
	// output: [ |>1  |>2  |>3]
}