Update deps

* Use go-eta library from calculating ETA
* Fix linter issues
* Add testify library for tests

README.md

@@ -29,9 +29,10 @@ func f(i int) error {
 func main() {
 
 	worker := gwp.New(4)         // Create pool with specified number of workers
+
 	worker.ShowProgress = true   // Enable progress indicator
-	worker.ShowProgress = true // Show processing speed in progress indicator
-	worker.EstimateCount = 100 // Set total number on jobs to calculate ETA
+	worker.ShowSpeed = true      // Show processing speed in progress indicator
+	worker.SetEstimateCount(100) // Set total number on jobs to calculate ETA
 
 	for i := 0; i < 100; i++ {
 		n := i

go.mod

@@ -1,3 +1,8 @@
 module github.com/nxshock/gwp
 
 go 1.16
+
+require (
+	github.com/nxshock/go-eta v0.1.1
+	github.com/stretchr/testify v1.8.0
+)

go.sum

@@ -0,0 +1,18 @@
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/nxshock/go-eta v0.1.0 h1:rcy8rNPaVeL3f3c5rJRLvho0FErUJThD0+vihxA7t9c=
+github.com/nxshock/go-eta v0.1.0/go.mod h1:hZ59FHIJSpPeZk38pd/3zUkI4H31hAQ2oFw+NgdU+SA=
+github.com/nxshock/go-eta v0.1.1 h1:N4wi3wjrXJGiheYF4zBIjOwugM+++NWsB1fpeRZaHS4=
+github.com/nxshock/go-eta v0.1.1/go.mod h1:hZ59FHIJSpPeZk38pd/3zUkI4H31hAQ2oFw+NgdU+SA=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0 h1:pSgiaMZlXftHpm5L7V1+rVB+AZJydKsMxsQBIJw4PKk=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

gwp.go

@@ -1,11 +1,14 @@
 package gwp
 
 import (
+	"bytes"
 	"fmt"
 	"os"
 	"runtime"
 	"sync"
 	"time"
+
+	"github.com/nxshock/go-eta"
 )
 
 // WorkerPool represents pool of workers.
@@ -15,17 +18,21 @@ type WorkerPool struct {
 	stopChan   chan struct{}
 	wg         sync.WaitGroup
 
-	EstimateCount int
+	estimateCount int
 	ShowProgress  bool
 	ShowSpeed     bool
 
 	processedCount int     // processed jobs count
 	errorCount     int     // processed jobs count that returned error
 	currentSpeed   float64 // speed calculated for last minute
+
+	eta *eta.Calculator
+
+	lastProgressMessage string
 }
 
 // New creates new pool of workers with specified goroutine count.
-// If specified number of workers less than 1, runtume.NumCPU() is used.
+// If specified number of workers less than 1, runtime.NumCPU() is used.
 func New(threadCount int) *WorkerPool {
 	if threadCount <= 0 {
 		threadCount = runtime.NumCPU()
@@ -34,7 +41,8 @@ func New(threadCount int) *WorkerPool {
 	workerPool := &WorkerPool{
 		jobChan:    make(chan func() error),
 		resultChan: make(chan error),
-		stopChan:   make(chan struct{})}
+		stopChan:   make(chan struct{}),
+		eta:        eta.New(0)}
 
 	workerPool.wg.Add(threadCount)
 
@@ -55,13 +63,13 @@ func New(threadCount int) *WorkerPool {
 			select {
 			case <-tickerUpdateText.C:
 				if !newLined {
-					fmt.Fprintf(os.Stderr, endLine)
+					fmt.Fprint(os.Stderr, endLine)
 					newLined = true
 				}
 
-				workerPool.printProgress()
+				_ = workerPool.printProgress()
 			case <-tickerCalculateEta.C:
-				workerPool.currentSpeed = float64(workerPool.processedCount-prevPos) * float64(time.Second) / float64(time.Now().Sub(prevTime))
+				workerPool.currentSpeed = float64(workerPool.processedCount-prevPos) * float64(time.Second) / float64(time.Since(prevTime))
 				prevPos = workerPool.processedCount
 				prevTime = time.Now()
 			case err := <-workerPool.resultChan:
@@ -69,6 +77,7 @@ func New(threadCount int) *WorkerPool {
 					workerPool.errorCount++
 				}
 				workerPool.processedCount++
+				workerPool.eta.Increment(1)
 			case <-workerPool.stopChan:
 				return
 			}
@@ -88,36 +97,54 @@ func New(threadCount int) *WorkerPool {
 	return workerPool
 }
 
-func (workerPool *WorkerPool) printProgress() {
+func (workerPool *WorkerPool) SetEstimateCount(n int) {
+	workerPool.estimateCount = n
+	workerPool.eta.TotalCount = n
+}
+
+func (workerPool *WorkerPool) printProgress() error {
 	if !workerPool.ShowProgress {
-		return
+		return nil
 	}
 
-	fmt.Fprintf(os.Stderr, newLine)
+	buf := new(bytes.Buffer)
 
-	if workerPool.EstimateCount == 0 {
-		fmt.Fprintf(os.Stderr, "Progress: %d", workerPool.processedCount)
+	fmt.Fprint(buf, newLine)
+
+	if workerPool.estimateCount == 0 {
+		fmt.Fprintf(buf, "Progress: %d", workerPool.processedCount)
 	} else {
-		fmt.Fprintf(os.Stderr, "Progress: %.1f%% (%d / %d)",
-			float64(workerPool.processedCount*100)/float64(workerPool.EstimateCount), workerPool.processedCount, workerPool.EstimateCount)
+		fmt.Fprintf(buf, "Progress: %.1f%% (%d / %d)",
+			float64(workerPool.processedCount*100)/float64(workerPool.estimateCount), workerPool.processedCount, workerPool.estimateCount)
 	}
 
 	if workerPool.errorCount > 0 {
-		fmt.Fprintf(os.Stderr, "    Errors: %d (%.1f%%)",
-			workerPool.errorCount, float64(workerPool.errorCount*100)/float64(workerPool.EstimateCount))
+		fmt.Fprintf(buf, "    Errors: %d (%.1f%%)",
+			workerPool.errorCount, float64(workerPool.errorCount*100)/float64(workerPool.estimateCount))
 	}
 
-	if workerPool.currentSpeed > 0 {
-		if workerPool.EstimateCount > 0 {
-			fmt.Fprintf(os.Stderr, "    ETA: %s", fmtDuration(time.Second*time.Duration(float64(workerPool.EstimateCount-workerPool.processedCount)/workerPool.currentSpeed)))
+	if workerPool.estimateCount > 0 {
+		fmt.Fprintf(buf, "    ETA: %s", fmtDuration(time.Until(workerPool.eta.Average())))
 	}
 
-		if workerPool.ShowSpeed {
-			fmt.Fprintf(os.Stderr, "Speed: %.2f rps", workerPool.currentSpeed)
-		}
+	if workerPool.currentSpeed > 0 && workerPool.ShowSpeed {
+		fmt.Fprintf(buf, "    Speed: %.2f rps", workerPool.currentSpeed)
 	}
 
-	fmt.Fprint(os.Stderr, endLine)
+	fmt.Fprint(buf, endLine)
+
+	if buf.String() == workerPool.lastProgressMessage {
+		return nil
+	}
+
+	workerPool.lastProgressMessage = buf.String()
+
+	_, err := buf.WriteTo(os.Stderr)
+	if err != nil {
+		return err
+	}
+
+	return nil
 }
 
 // Add sends specified task for execution.
@@ -132,7 +159,7 @@ func (workerPool *WorkerPool) CloseAndWait() {
 	workerPool.stopChan <- struct{}{}
 	close(workerPool.resultChan)
 
-	workerPool.printProgress()
+	_ = workerPool.printProgress()
 }
 
 // ErrorCount returns total error count.