refactor: add a semaphore lib

Simple lib for better semaphore semanthics.

internal/http/http.go

@@ -18,6 +18,7 @@ import (
 	"github.com/goreleaser/goreleaser/config"
 	"github.com/goreleaser/goreleaser/context"
 	"github.com/goreleaser/goreleaser/internal/artifact"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 	"github.com/goreleaser/goreleaser/pipeline"
 )
 
@@ -157,15 +158,13 @@ func Upload(ctx *context.Context, puts []config.Put, kind string, check Response
 }
 
 func runPipeByFilter(ctx *context.Context, put config.Put, filter artifact.Filter, kind string, check ResponseChecker) error {
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	var g errgroup.Group
 	for _, artifact := range ctx.Artifacts.Filter(filter).List() {
-		sem <- true
+		sem.Acquire()
 		artifact := artifact
 		g.Go(func() error {
-			defer func() {
-				<-sem
-			}()
+			defer sem.Release()
 			return uploadAsset(ctx, put, artifact, kind, check)
 		})
 	}

internal/semaphore/sem.go

@@ -0,0 +1,20 @@
+// Package semaphore provides a small and simple semaphore lib for goreleaser.
+package semaphore
+
+// Semaphore is the semaphore itself
+type Semaphore chan bool
+
+// New returns a new semaphore of a given size.
+func New(size int) Semaphore {
+	return make(Semaphore, size)
+}
+
+// Acquire acquires one semaphore permit.
+func (s Semaphore) Acquire() {
+	s <- true
+}
+
+// Release releases one semaphore permit
+func (s Semaphore) Release() {
+	<-s
+}

internal/semaphore/sem_test.go

@@ -0,0 +1,20 @@
+package semaphore
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestSemaphore(t *testing.T) {
+	var sem = New(1)
+	var counter = 0
+	for i := 0; i < 10; i++ {
+		sem.Acquire()
+		go func() {
+			counter++
+			sem.Release()
+		}()
+	}
+	require.Equal(t, counter, 9)
+}

pipeline/build/build.go

@@ -21,6 +21,7 @@ import (
 
 	// langs to init
 	_ "github.com/goreleaser/goreleaser/internal/builders/golang"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 )
 
 // Pipe for build
@@ -71,16 +72,14 @@ func runPipeOnBuild(ctx *context.Context, build config.Build) error {
 	if err := runHook(ctx, build.Env, build.Hooks.Pre); err != nil {
 		return errors.Wrap(err, "pre hook failed")
 	}
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	var g errgroup.Group
 	for _, target := range build.Targets {
-		sem <- true
+		sem.Acquire()
 		target := target
 		build := build
 		g.Go(func() error {
-			defer func() {
-				<-sem
-			}()
+			defer sem.Release()
 			return doBuild(ctx, build, target)
 		})
 	}

pipeline/checksums/checksums.go

@@ -15,6 +15,7 @@ import (
 	"github.com/goreleaser/goreleaser/checksum"
 	"github.com/goreleaser/goreleaser/context"
 	"github.com/goreleaser/goreleaser/internal/artifact"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 )
 
 // Pipe for checksums
@@ -49,7 +50,7 @@ func (Pipe) Run(ctx *context.Context) (err error) {
 	defer file.Close() // nolint: errcheck
 
 	var g errgroup.Group
-	var semaphore = make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for _, artifact := range ctx.Artifacts.Filter(
 		artifact.Or(
 			artifact.ByType(artifact.UploadableArchive),
@@ -57,12 +58,10 @@ func (Pipe) Run(ctx *context.Context) (err error) {
 			artifact.ByType(artifact.LinuxPackage),
 		),
 	).List() {
-		semaphore <- true
+		sem.Acquire()
 		artifact := artifact
 		g.Go(func() error {
-			defer func() {
-				<-semaphore
-			}()
+			defer sem.Release()
 			return checksums(ctx, file, artifact)
 		})
 	}

pipeline/docker/docker.go

@@ -19,6 +19,7 @@ import (
 	"github.com/goreleaser/goreleaser/context"
 	"github.com/goreleaser/goreleaser/internal/artifact"
 	"github.com/goreleaser/goreleaser/internal/deprecate"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 	"github.com/goreleaser/goreleaser/pipeline"
 )
 
@@ -81,15 +82,13 @@ func (Pipe) Run(ctx *context.Context) error {
 
 func doRun(ctx *context.Context) error {
 	var g errgroup.Group
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for i, docker := range ctx.Config.Dockers {
 		docker := docker
 		seed := i
-		sem <- true
+		sem.Acquire()
 		g.Go(func() error {
-			defer func() {
-				<-sem
-			}()
+			defer sem.Release()
 			log.WithField("docker", docker).Debug("looking for binaries matching")
 			var binaries = ctx.Artifacts.Filter(
 				artifact.And(

pipeline/nfpm/nfpm.go

@@ -22,6 +22,7 @@ import (
 	"github.com/goreleaser/goreleaser/internal/artifact"
 	"github.com/goreleaser/goreleaser/internal/filenametemplate"
 	"github.com/goreleaser/goreleaser/internal/linux"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 	"github.com/goreleaser/goreleaser/pipeline"
 )
 
@@ -63,17 +64,15 @@ func doRun(ctx *context.Context) error {
 		artifact.ByGoos("linux"),
 	)).GroupByPlatform()
 	var g errgroup.Group
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for _, format := range ctx.Config.NFPM.Formats {
 		for platform, artifacts := range linuxBinaries {
-			sem <- true
+			sem.Acquire()
 			format := format
 			arch := linux.Arch(platform)
 			artifacts := artifacts
 			g.Go(func() error {
-				defer func() {
-					<-sem
-				}()
+				defer sem.Release()
 				return create(ctx, format, arch, artifacts)
 			})
 		}

pipeline/release/release.go

@@ -9,6 +9,7 @@ import (
 	"github.com/goreleaser/goreleaser/context"
 	"github.com/goreleaser/goreleaser/internal/artifact"
 	"github.com/goreleaser/goreleaser/internal/client"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 	"github.com/goreleaser/goreleaser/pipeline"
 )
 
@@ -66,7 +67,7 @@ func doRun(ctx *context.Context, c client.Client) error {
 		return err
 	}
 	var g errgroup.Group
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for _, artifact := range ctx.Artifacts.Filter(
 		artifact.Or(
 			artifact.ByType(artifact.UploadableArchive),
@@ -76,12 +77,10 @@ func doRun(ctx *context.Context, c client.Client) error {
 			artifact.ByType(artifact.LinuxPackage),
 		),
 	).List() {
-		sem <- true
+		sem.Acquire()
 		artifact := artifact
 		g.Go(func() error {
-			defer func() {
-				<-sem
-			}()
+			defer sem.Release()
 			return upload(ctx, c, releaseID, artifact)
 		})
 	}

pipeline/s3/s3.go

@@ -14,6 +14,7 @@ import (
 	"github.com/goreleaser/goreleaser/context"
 	"github.com/goreleaser/goreleaser/internal/artifact"
 	"github.com/goreleaser/goreleaser/internal/nametemplate"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -45,14 +46,12 @@ func (Pipe) Default(ctx *context.Context) error {
 // Run the pipe
 func (Pipe) Run(ctx *context.Context) error {
 	var g errgroup.Group
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for _, conf := range ctx.Config.S3 {
 		conf := conf
-		sem <- true
+		sem.Acquire()
 		g.Go(func() error {
-			defer func() {
-				<-sem
-			}()
+			defer sem.Release()
 			return upload(ctx, conf)
 		})
 	}
@@ -80,7 +79,7 @@ func upload(ctx *context.Context, conf config.S3) error {
 	}
 
 	var g errgroup.Group
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for _, artifact := range ctx.Artifacts.Filter(
 		artifact.Or(
 			artifact.ByType(artifact.UploadableArchive),
@@ -90,12 +89,10 @@ func upload(ctx *context.Context, conf config.S3) error {
 			artifact.ByType(artifact.LinuxPackage),
 		),
 	).List() {
-		sem <- true
+		sem.Acquire()
 		artifact := artifact
 		g.Go(func() error {
-			defer func() {
-				<-sem
-			}()
+			defer sem.Release()
 			f, err := os.Open(artifact.Path)
 			if err != nil {
 				return err

pipeline/snapcraft/snapcraft.go

@@ -18,6 +18,7 @@ import (
 	"github.com/goreleaser/goreleaser/internal/artifact"
 	"github.com/goreleaser/goreleaser/internal/filenametemplate"
 	"github.com/goreleaser/goreleaser/internal/linux"
+	"github.com/goreleaser/goreleaser/internal/semaphore"
 	"github.com/goreleaser/goreleaser/pipeline"
 )
 
@@ -84,14 +85,14 @@ func (Pipe) Run(ctx *context.Context) error {
 	}
 
 	var g errgroup.Group
-	sem := make(chan bool, ctx.Parallelism)
+	var sem = semaphore.New(ctx.Parallelism)
 	for platform, binaries := range ctx.Artifacts.Filter(
 		artifact.And(
 			artifact.ByGoos("linux"),
 			artifact.ByType(artifact.Binary),
 		),
 	).GroupByPlatform() {
-		sem <- true
+		sem.Acquire()
 		arch := linux.Arch(platform)
 		if arch == "armel" {
 			log.WithField("arch", arch).Warn("ignored unsupported arch")
@@ -99,9 +100,7 @@ func (Pipe) Run(ctx *context.Context) error {
 		}
 		binaries := binaries
 		g.Go(func() error {
-			go func() {
-				<-sem
-			}()
+			defer sem.Release()
 			return create(ctx, arch, binaries)
 		})
 	}