Merge pull request #484 from goreleaser/pull-483

feat: docker link for extra folders

pipeline/docker/docker.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"strings"
 	"text/template"
 
 	"github.com/apex/log"
@@ -127,7 +128,7 @@ func process(ctx *context.Context, docker config.Docker, artifact artifact.Artif
 		return errors.Wrap(err, "failed to link dockerfile")
 	}
 	for _, file := range docker.Files {
-		if err := os.Link(file, filepath.Join(root, filepath.Base(file))); err != nil {
+		if err := link(file, filepath.Join(root, filepath.Base(file))); err != nil {
 			return errors.Wrapf(err, "failed to link extra file '%s'", file)
 		}
 	}
@@ -143,6 +144,26 @@ func process(ctx *context.Context, docker config.Docker, artifact artifact.Artif
 	return publish(ctx, docker, image, latest)
 }
 
+// walks the src, recreating dirs and hard-linking files
+func link(src, dest string) error {
+	return filepath.Walk(src, func(path string, info os.FileInfo, err error) error {
+		// We have the following:
+		// - src = "a/b"
+		// - dest = "dist/linuxamd64/b"
+		// - path = "a/b/c.txt"
+		// So we join "a/b" with "c.txt" and use it as the destination.
+		var dst = filepath.Join(dest, strings.Replace(path, src, "", 1))
+		log.WithFields(log.Fields{
+			"src": path,
+			"dst": dst,
+		}).Info("extra file")
+		if info.IsDir() {
+			return os.MkdirAll(dst, info.Mode())
+		}
+		return os.Link(path, dst)
+	})
+}
+
 func publish(ctx *context.Context, docker config.Docker, image, latest string) error {
 	// TODO: improve this so it can log it to stdout
 	if !ctx.Publish {

pipeline/docker/docker_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/goreleaser/goreleaser/internal/artifact"
 	"github.com/goreleaser/goreleaser/pipeline"
 	"github.com/stretchr/testify/assert"
+	"syscall"
 )
 
 func killAndRm(t *testing.T) {
@@ -236,3 +237,96 @@ func TestDefaultSet(t *testing.T) {
 	assert.Equal(t, "{{ .Version }}", docker.TagTemplate)
 	assert.Equal(t, "Dockerfile.foo", docker.Dockerfile)
 }
+
+func TestLinkFile(t *testing.T) {
+	const srcFile = "/tmp/test"
+	const dstFile = "/tmp/linked"
+	err := ioutil.WriteFile(srcFile, []byte("foo"), 0644)
+	if err != nil {
+		t.Log("Cannot setup test file")
+		t.Fail()
+	}
+	err = link(srcFile, dstFile)
+	if err != nil {
+		t.Log("Failed to link: ", err)
+		t.Fail()
+	}
+	if inode(srcFile) != inode(dstFile) {
+		t.Log("Inodes do not match, destination file is not a link")
+		t.Fail()
+	}
+	// cleanup
+	os.Remove(srcFile)
+	os.Remove(dstFile)
+}
+
+func TestLinkDirectory(t *testing.T) {
+	const srcDir = "/tmp/testdir"
+	const testFile = "test"
+	const dstDir = "/tmp/linkedDir"
+
+	os.Mkdir(srcDir, 0755)
+	err := ioutil.WriteFile(srcDir+"/"+testFile, []byte("foo"), 0644)
+	if err != nil {
+		t.Log("Cannot setup test file")
+		t.Fail()
+	}
+	err = link(srcDir, dstDir)
+	if err != nil {
+		t.Log("Failed to link: ", err)
+		t.Fail()
+	}
+	if inode(srcDir+"/"+testFile) != inode(dstDir+"/"+testFile) {
+		t.Log("Inodes do not match, destination file is not a link")
+		t.Fail()
+	}
+
+	// cleanup
+	os.RemoveAll(srcDir)
+	os.RemoveAll(dstDir)
+}
+
+func TestLinkTwoLevelDirectory(t *testing.T) {
+	const srcDir = "/tmp/testdir"
+	const srcLevel2 = srcDir+"/level2"
+	const testFile = "test"
+	const dstDir = "/tmp/linkedDir"
+
+	os.Mkdir(srcDir, 0755)
+	os.Mkdir(srcLevel2, 0755)
+	err := ioutil.WriteFile(srcDir+"/"+testFile, []byte("foo"), 0644)
+	if err != nil {
+		t.Log("Cannot setup test file")
+		t.Fail()
+	}
+	err = ioutil.WriteFile(srcLevel2+"/"+testFile, []byte("foo"), 0644)
+	if err != nil {
+		t.Log("Cannot setup test file")
+		t.Fail()
+	}
+	err = link(srcDir, dstDir)
+	if err != nil {
+		t.Log("Failed to link: ", err)
+		t.Fail()
+	}
+	if inode(srcDir+"/"+testFile) != inode(dstDir+"/"+testFile) {
+		t.Log("Inodes do not match")
+		t.Fail()
+	}
+	if inode(srcLevel2+"/"+testFile) != inode(dstDir+"/level2/"+testFile) {
+		t.Log("Inodes do not match")
+		t.Fail()
+	}
+	// cleanup
+	os.RemoveAll(srcDir)
+	os.RemoveAll(dstDir)
+}
+
+func inode(file string) uint64 {
+	fileInfo, err := os.Stat(file)
+	if err != nil {
+		return 0
+	}
+	stat := fileInfo.Sys().(*syscall.Stat_t)
+	return stat.Ino
+}