Enable Go build tags

This enables go build tags so the GCS and OSS driver support is
available in the binary distributed via the image build by Dockerfile.

This led to quite a few fixes in the GCS and OSS packages raised as
warning by golang-ci linter.

Signed-off-by: Milos Gajdos <milosthegajdos@gmail.com>
(cherry picked from commit 6b388b1ba6)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

BUILDING.md

@@ -114,4 +114,4 @@ the registry binary generated in the "./bin" directory:
 ### Optional build tags
 
 Optional [build tags](http://golang.org/pkg/go/build/) can be provided using
-the environment variable `DOCKER_BUILDTAGS`.
+the environment variable `BUILDTAGS`.

Dockerfile

@@ -22,12 +22,12 @@ RUN --mount=target=. \
 FROM base AS build
 ARG TARGETPLATFORM
 ARG LDFLAGS="-s -w"
-ARG BUILDTAGS="include_oss include_gcs"
+ARG BUILDTAGS="include_oss,include_gcs"
 RUN --mount=type=bind,target=/go/src/github.com/docker/distribution,rw \
     --mount=type=cache,target=/root/.cache/go-build \
     --mount=target=/go/pkg/mod,type=cache \
     --mount=type=bind,source=/tmp/.ldflags,target=/tmp/.ldflags,from=version \
-      set -x ; xx-go build -trimpath -ldflags "$(cat /tmp/.ldflags) ${LDFLAGS}" -tags="${BUILDTAGS}" -o /usr/bin/registry ./cmd/registry \
+      set -x ; xx-go build -tags "${BUILDTAGS}" -trimpath -ldflags "$(cat /tmp/.ldflags) ${LDFLAGS}" -o /usr/bin/registry ./cmd/registry \
       && xx-verify --static /usr/bin/registry
 
 FROM scratch AS binary

registry/storage/driver/gcs/gcs.go

@@ -1,18 +1,17 @@
+//go:build include_gcs
+// +build include_gcs
+
 // Package gcs provides a storagedriver.StorageDriver implementation to
 // store blobs in Google cloud storage.
 //
 // This package leverages the google.golang.org/cloud/storage client library
-//for interfacing with gcs.
+// for interfacing with gcs.
 //
 // Because gcs is a key, value store the Stat call does not support last modification
 // time for directories (directories are an abstraction for key, value stores)
 //
 // Note that the contents of incomplete uploads are not accessible even though
 // Stat returns their length
-//
-//go:build include_gcs
-// +build include_gcs
-
 package gcs
 
 import (
@@ -62,7 +61,6 @@ var rangeHeader = regexp.MustCompile(`^bytes=([0-9])+-([0-9]+)$`)
 // driverParameters is a struct that encapsulates all of the driver parameters after all values have been set
 type driverParameters struct {
 	bucket        string
-	config        *jwt.Config
 	email         string
 	privateKey    []byte
 	client        *http.Client
@@ -88,6 +86,8 @@ func (factory *gcsDriverFactory) Create(parameters map[string]interface{}) (stor
 	return FromParameters(parameters)
 }
 
+var _ storagedriver.StorageDriver = &driver{}
+
 // driver is a storagedriver.StorageDriver implementation backed by GCS
 // Objects are stored at absolute keys in the provided bucket.
 type driver struct {
@@ -298,7 +298,7 @@ func (d *driver) Reader(context context.Context, path string, offset int64) (io.
 				if err != nil {
 					return nil, err
 				}
-				if offset == int64(obj.Size) {
+				if offset == obj.Size {
 					return ioutil.NopCloser(bytes.NewReader([]byte{})), nil
 				}
 				return nil, storagedriver.InvalidOffsetError{Path: path, Offset: offset}
@@ -434,7 +434,6 @@ func putContentsClose(wc *storage.Writer, contents []byte) error {
 		}
 	}
 	if err != nil {
-		wc.CloseWithError(err)
 		return err
 	}
 	return wc.Close()
@@ -614,10 +613,10 @@ func (d *driver) Stat(context context.Context, path string) (storagedriver.FileI
 	//try to get as folder
 	dirpath := d.pathToDirKey(path)
 
-	var query *storage.Query
-	query = &storage.Query{}
-	query.Prefix = dirpath
-	query.MaxResults = 1
+	query := &storage.Query{
+		Prefix:     dirpath,
+		MaxResults: 1,
+	}
 
 	objects, err := storageListObjects(gcsContext, d.bucket, query)
 	if err != nil {
@@ -639,12 +638,12 @@ func (d *driver) Stat(context context.Context, path string) (storagedriver.FileI
 }
 
 // List returns a list of the objects that are direct descendants of the
-//given path.
+// given path.
 func (d *driver) List(context context.Context, path string) ([]string, error) {
-	var query *storage.Query
-	query = &storage.Query{}
-	query.Delimiter = "/"
-	query.Prefix = d.pathToDirKey(path)
+	query := &storage.Query{
+		Delimiter: "/",
+		Prefix:    d.pathToDirKey(path),
+	}
 	list := make([]string, 0, 64)
 	for {
 		objects, err := storageListObjects(d.context(context), d.bucket, query)

registry/storage/driver/gcs/gcs_test.go

@@ -59,7 +59,7 @@ func init() {
 			panic(fmt.Sprintf("Error reading JWT config : %s", err))
 		}
 		email = jwtConfig.Email
-		privateKey = []byte(jwtConfig.PrivateKey)
+		privateKey = jwtConfig.PrivateKey
 		if len(privateKey) == 0 {
 			panic("Error reading JWT config : missing private_key property")
 		}
@@ -260,6 +260,9 @@ func TestEmptyRootList(t *testing.T) {
 		}
 	}()
 	keys, err := emptyRootDriver.List(ctx, "/")
+	if err != nil {
+		t.Fatalf("unexpected error listing empty root content: %v", err)
+	}
 	for _, path := range keys {
 		if !storagedriver.PathRegexp.MatchString(path) {
 			t.Fatalf("unexpected string in path: %q != %q", path, storagedriver.PathRegexp)
@@ -267,6 +270,9 @@ func TestEmptyRootList(t *testing.T) {
 	}
 
 	keys, err = slashRootDriver.List(ctx, "/")
+	if err != nil {
+		t.Fatalf("unexpected error listing slash root content: %v", err)
+	}
 	for _, path := range keys {
 		if !storagedriver.PathRegexp.MatchString(path) {
 			t.Fatalf("unexpected string in path: %q != %q", path, storagedriver.PathRegexp)

registry/storage/driver/oss/oss.go

@@ -1,3 +1,6 @@
+//go:build include_oss
+// +build include_oss
+
 // Package oss provides a storagedriver.StorageDriver implementation to
 // store blobs in Aliyun OSS cloud storage.
 //
@@ -6,10 +9,6 @@
 //
 // Because OSS is a key, value store the Stat call does not support last modification
 // time for directories (directories are an abstraction for key, value stores)
-//
-//go:build include_oss
-// +build include_oss
-
 package oss
 
 import (
@@ -68,6 +67,8 @@ func (factory *ossDriverFactory) Create(parameters map[string]interface{}) (stor
 	return FromParameters(parameters)
 }
 
+var _ storagedriver.StorageDriver = &driver{}
+
 type driver struct {
 	Client        *oss.Client
 	Bucket        *oss.Bucket
@@ -498,11 +499,6 @@ func parseError(path string, err error) error {
 	return err
 }
 
-func hasCode(err error, code string) bool {
-	ossErr, ok := err.(*oss.Error)
-	return ok && ossErr.Code == code
-}
-
 func (d *driver) getOptions() oss.Options {
 	return oss.Options{ServerSideEncryption: d.Encrypt}
 }

registry/storage/driver/oss/oss_test.go

@@ -128,6 +128,9 @@ func TestEmptyRootList(t *testing.T) {
 	defer rootedDriver.Delete(ctx, filename)
 
 	keys, err := emptyRootDriver.List(ctx, "/")
+	if err != nil {
+		t.Fatalf("unexpected error listing empty root content: %v", err)
+	}
 	for _, path := range keys {
 		if !storagedriver.PathRegexp.MatchString(path) {
 			t.Fatalf("unexpected string in path: %q != %q", path, storagedriver.PathRegexp)
@@ -135,6 +138,9 @@ func TestEmptyRootList(t *testing.T) {
 	}
 
 	keys, err = slashRootDriver.List(ctx, "/")
+	if err != nil {
+		t.Fatalf("unexpected error listing slash root content: %v", err)
+	}
 	for _, path := range keys {
 		if !storagedriver.PathRegexp.MatchString(path) {
 			t.Fatalf("unexpected string in path: %q != %q", path, storagedriver.PathRegexp)