podman-remote fix sending tar content

1.) podman cannot send proper dockerfile when it is not inside root
folder.
2.) support for sending symlinks and folders inside context dir
3.) when sending context dir as tar to remote, prevent sending items
inside .dockerignore

Signed-off-by: Kazım SARIKAYA <kazimsarikaya@sanaldiyar.com>

1 files changed, 115 insertions, 23 deletions

diff --git a/pkg/bindings/images/build.go b/pkg/bindings/images/build.go
index d34ab87d9..02765816f 100644
--- a/pkg/bindings/images/build.go
+++ b/pkg/bindings/images/build.go
@@ -2,6 +2,7 @@ package images
 
 import (
 	"archive/tar"
+	"compress/gzip"
 	"context"
 	"encoding/json"
 	"io"
@@ -18,6 +19,7 @@ import (
 	"github.com/containers/podman/v2/pkg/auth"
 	"github.com/containers/podman/v2/pkg/bindings"
 	"github.com/containers/podman/v2/pkg/domain/entities"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/docker/go-units"
 	"github.com/hashicorp/go-multierror"
 	jsoniter "github.com/json-iterator/go"
@@ -138,12 +140,38 @@ func Build(ctx context.Context, containerFiles []string, options entities.BuildO
 	entries := make([]string, len(containerFiles))
 	copy(entries, containerFiles)
 	entries = append(entries, options.ContextDirectory)
-	tarfile, err := nTar(entries...)
+
+	excludes := options.Excludes
+	if len(excludes) == 0 {
+		excludes, err = parseDockerignore(options.ContextDirectory)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	tarfile, err := nTar(excludes, entries...)
 	if err != nil {
+		logrus.Errorf("cannot tar container entries %v error: %v", entries, err)
 		return nil, err
 	}
 	defer tarfile.Close()
-	params.Set("dockerfile", filepath.Base(containerFiles[0]))
+
+	containerFile, err := filepath.Abs(entries[0])
+	if err != nil {
+		logrus.Errorf("cannot find absolute path of %v: %v", entries[0], err)
+		return nil, err
+	}
+	contextDir, err := filepath.Abs(entries[1])
+	if err != nil {
+		logrus.Errorf("cannot find absolute path of %v: %v", entries[1], err)
+		return nil, err
+	}
+
+	if strings.HasPrefix(containerFile, contextDir+string(filepath.Separator)) {
+		containerFile = strings.TrimPrefix(containerFile, contextDir+string(filepath.Separator))
+	}
+
+	params.Set("dockerfile", containerFile)
 
 	conn, err := bindings.GetClient(ctx)
 	if err != nil {
@@ -200,52 +228,116 @@ func Build(ctx context.Context, containerFiles []string, options entities.BuildO
 	}
 }
 
-func nTar(sources ...string) (io.ReadCloser, error) {
+func nTar(excludes []string, sources ...string) (io.ReadCloser, error) {
+	pm, err := fileutils.NewPatternMatcher(excludes)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error processing excludes list %v", excludes)
+	}
+
 	if len(sources) == 0 {
 		return nil, errors.New("No source(s) provided for build")
 	}
 
 	pr, pw := io.Pipe()
-	tw := tar.NewWriter(pw)
+	gw := gzip.NewWriter(pw)
+	tw := tar.NewWriter(gw)
 
 	var merr error
 	go func() {
 		defer pw.Close()
+		defer gw.Close()
 		defer tw.Close()
 
 		for _, src := range sources {
-			s := src
-			err := filepath.Walk(s, func(path string, info os.FileInfo, err error) error {
+			s, err := filepath.Abs(src)
+			if err != nil {
+				logrus.Errorf("cannot stat one of source context: %v", err)
+				merr = multierror.Append(merr, err)
+				return
+			}
+
+			err = filepath.Walk(s, func(path string, info os.FileInfo, err error) error {
 				if err != nil {
 					return err
 				}
-				if !info.Mode().IsRegular() || path == s {
-					return nil
-				}
 
-				f, lerr := os.Open(path)
-				if lerr != nil {
-					return lerr
+				if path == s {
+					return nil // skip root dir
 				}
 
 				name := strings.TrimPrefix(path, s+string(filepath.Separator))
-				hdr, lerr := tar.FileInfoHeader(info, name)
-				if lerr != nil {
-					f.Close()
-					return lerr
+
+				excluded, err := pm.Matches(filepath.ToSlash(name)) // nolint:staticcheck
+				if err != nil {
+					return errors.Wrapf(err, "error checking if %q is excluded", name)
 				}
-				hdr.Name = name
-				if lerr := tw.WriteHeader(hdr); lerr != nil {
-					f.Close()
-					return lerr
+				if excluded {
+					return nil
 				}
 
-				_, cerr := io.Copy(tw, f)
-				f.Close()
-				return cerr
+				if info.Mode().IsRegular() { // add file item
+					f, lerr := os.Open(path)
+					if lerr != nil {
+						return lerr
+					}
+
+					hdr, lerr := tar.FileInfoHeader(info, name)
+					if lerr != nil {
+						f.Close()
+						return lerr
+					}
+					hdr.Name = name
+					if lerr := tw.WriteHeader(hdr); lerr != nil {
+						f.Close()
+						return lerr
+					}
+
+					_, cerr := io.Copy(tw, f)
+					f.Close()
+					return cerr
+				} else if info.Mode().IsDir() { // add folders
+					hdr, lerr := tar.FileInfoHeader(info, name)
+					if lerr != nil {
+						return lerr
+					}
+					hdr.Name = name
+					if lerr := tw.WriteHeader(hdr); lerr != nil {
+						return lerr
+					}
+				} else if info.Mode()&os.ModeSymlink != 0 { // add symlinks as it, not content
+					link, err := os.Readlink(path)
+					if err != nil {
+						return err
+					}
+					hdr, lerr := tar.FileInfoHeader(info, link)
+					if lerr != nil {
+						return lerr
+					}
+					hdr.Name = name
+					if lerr := tw.WriteHeader(hdr); lerr != nil {
+						return lerr
+					}
+				} //skip other than file,folder and symlinks
+				return nil
 			})
 			merr = multierror.Append(merr, err)
 		}
 	}()
 	return pr, merr
 }
+
+func parseDockerignore(root string) ([]string, error) {
+	ignore, err := ioutil.ReadFile(filepath.Join(root, ".dockerignore"))
+	if err != nil && !os.IsNotExist(err) {
+		return nil, errors.Wrapf(err, "error reading .dockerignore: '%s'", root)
+	}
+	rawexcludes := strings.Split(string(ignore), "\n")
+	excludes := make([]string, 0, len(rawexcludes))
+	for _, e := range rawexcludes {
+		if len(e) == 0 || e[0] == '#' {
+			continue
+		}
+		excludes = append(excludes, e)
+	}
+	return excludes, nil
+}