feat: add file and directory report skeleton

cmd/chisel/cmd_cut.go

@@ -99,11 +99,12 @@ func (cmd *cmdCut) Execute(args []string) error {
 		archives[archiveName] = openArchive
 	}
 
-	return slicer.Run(&slicer.RunOptions{
+	_, err = slicer.Run(&slicer.RunOptions{
 		Selection: selection,
 		Archives:  archives,
 		TargetDir: cmd.RootDir,
 	})
+	return err
 }
 
 // TODO These need testing, and maybe moving into a common file.

internal/archive/archive_test.go

@@ -19,7 +19,6 @@ import (
 	"github.com/canonical/chisel/internal/archive"
 	"github.com/canonical/chisel/internal/archive/testarchive"
 	"github.com/canonical/chisel/internal/deb"
-	"github.com/canonical/chisel/internal/fsutil"
 	"github.com/canonical/chisel/internal/testutil"
 )
 
@@ -501,7 +500,6 @@ func (s *S) testOpenArchiveArch(c *C, release ubuntuRelease, arch string) {
 				{Path: "/hostname"},
 			},
 		},
-		Creator: fsutil.NewCreator(),
 	})
 	c.Assert(err, IsNil)
 

internal/deb/extract.go

@@ -25,7 +25,7 @@ type ExtractOptions struct {
 	TargetDir string
 	Extract   map[string][]ExtractInfo
 	Globbed   map[string][]string
-	Creator   *fsutil.Creator
+	Create    func(options *fsutil.CreateOptions) error
 }
 
 type ExtractInfo struct {
@@ -34,16 +34,26 @@ type ExtractInfo struct {
 	Optional bool
 }
 
-func checkExtractOptions(options *ExtractOptions) error {
+func getValidOptions(options *ExtractOptions) (*ExtractOptions, error) {
 	for extractPath, extractInfos := range options.Extract {
 		isGlob := strings.ContainsAny(extractPath, "*?")
 		if isGlob {
 			if len(extractInfos) != 1 || extractInfos[0].Path != extractPath || extractInfos[0].Mode != 0 {
-				return fmt.Errorf("when using wildcards source and target paths must match: %s", extractPath)
+				return nil, fmt.Errorf("when using wildcards source and target paths must match: %s", extractPath)
 			}
 		}
 	}
-	return nil
+
+	if options.Create == nil {
+		validOpts := *options
+		validOpts.Create = func(o *fsutil.CreateOptions) error {
+			_, err := fsutil.Create(o)
+			return err
+		}
+		return &validOpts, nil
+	}
+
+	return options, nil
 }
 
 func Extract(pkgReader io.Reader, options *ExtractOptions) (err error) {
@@ -55,12 +65,12 @@ func Extract(pkgReader io.Reader, options *ExtractOptions) (err error) {
 
 	logf("Extracting files from package %q...", options.Package)
 
-	err = checkExtractOptions(options)
+	validOpts, err := getValidOptions(options)
 	if err != nil {
 		return err
 	}
 
-	_, err = os.Stat(options.TargetDir)
+	_, err = os.Stat(validOpts.TargetDir)
 	if os.IsNotExist(err) {
 		return fmt.Errorf("target directory does not exist")
 	} else if err != nil {
@@ -100,7 +110,7 @@ func Extract(pkgReader io.Reader, options *ExtractOptions) (err error) {
 			dataReader = zstdReader
 		}
 	}
-	return extractData(dataReader, options)
+	return extractData(dataReader, validOpts)
 }
 
 func extractData(dataReader io.Reader, options *ExtractOptions) error {
@@ -186,7 +196,7 @@ func extractData(dataReader io.Reader, options *ExtractOptions) error {
 				// Base directory for extracted content. Relevant mainly to preserve
 				// the metadata, since the extracted content itself will also create
 				// any missing directories unaccounted for in the options.
-				err := options.Creator.Create(&fsutil.CreateOptions{
+				err := options.Create(&fsutil.CreateOptions{
 					Path:        filepath.Join(options.TargetDir, sourcePath),
 					Mode:        tarHeader.FileInfo().Mode(),
 					MakeParents: true,
@@ -227,7 +237,7 @@ func extractData(dataReader io.Reader, options *ExtractOptions) error {
 			if extractInfo.Mode != 0 {
 				tarHeader.Mode = int64(extractInfo.Mode)
 			}
-			err := options.Creator.Create(&fsutil.CreateOptions{
+			err := options.Create(&fsutil.CreateOptions{
 				Path:        targetPath,
 				Mode:        tarHeader.FileInfo().Mode(),
 				Data:        pathReader,

internal/deb/extract_test.go

@@ -2,6 +2,10 @@ package deb_test
 
 import (
 	"bytes"
+	"io/fs"
+	"path/filepath"
+	"sort"
+	"strings"
 
 	. "gopkg.in/check.v1"
 
@@ -14,9 +18,12 @@ type extractTest struct {
 	summary string
 	pkgdata []byte
 	options deb.ExtractOptions
+	hackopt func(o *deb.ExtractOptions)
 	globbed map[string][]string
 	result  map[string]string
-	error   string
+	// paths which the extractor did not create explicitly.
+	notCreated []string
+	error      string
 }
 
 var extractTests = []extractTest{{
@@ -60,8 +67,45 @@ var extractTests = []extractTest{{
 		"/etc/":               "dir 0755",
 		"/etc/os-release":     "symlink ../usr/lib/os-release",
 	},
+	notCreated: []string{},
+}, {
+	summary: "Extract a few entries, nil Create closure",
+	pkgdata: testutil.PackageData["base-files"],
+	options: deb.ExtractOptions{
+		Extract: map[string][]deb.ExtractInfo{
+			"/usr/bin/hello": []deb.ExtractInfo{{
+				Path: "/usr/bin/hello",
+			}},
+			"/etc/os-release": []deb.ExtractInfo{{
+				Path: "/etc/os-release",
+			}},
+			"/usr/lib/os-release": []deb.ExtractInfo{{
+				Path: "/usr/lib/os-release",
+			}},
+			"/usr/share/doc/": []deb.ExtractInfo{{
+				Path: "/usr/share/doc/",
+			}},
+			"/tmp/": []deb.ExtractInfo{{
+				Path: "/tmp/",
+			}},
+		},
+	},
+	result: map[string]string{
+		"/tmp/":               "dir 01777",
+		"/usr/":               "dir 0755",
+		"/usr/bin/":           "dir 0755",
+		"/usr/bin/hello":      "file 0775 eaf29575",
+		"/usr/share/":         "dir 0755",
+		"/usr/share/doc/":     "dir 0755",
+		"/usr/lib/":           "dir 0755",
+		"/usr/lib/os-release": "file 0644 ec6fae43",
+		"/etc/":               "dir 0755",
+		"/etc/os-release":     "symlink ../usr/lib/os-release",
+	},
+	hackopt: func(o *deb.ExtractOptions) {
+		o.Create = nil
+	},
 }, {
-
 	summary: "Copy a couple of entries elsewhere",
 	pkgdata: testutil.PackageData["base-files"],
 	options: deb.ExtractOptions{
@@ -83,8 +127,8 @@ var extractTests = []extractTest{{
 		"/usr/foo/bin/hello-2": "file 0600 eaf29575",
 		"/usr/other/":          "dir 0700",
 	},
+	notCreated: []string{"/usr/foo/", "/usr/foo/bin/"},
 }, {
-
 	summary: "Copy same file twice",
 	pkgdata: testutil.PackageData["base-files"],
 	options: deb.ExtractOptions{
@@ -102,6 +146,7 @@ var extractTests = []extractTest{{
 		"/usr/bin/hello": "file 0775 eaf29575",
 		"/usr/bin/hallo": "file 0775 eaf29575",
 	},
+	notCreated: []string{},
 }, {
 	summary: "Globbing a single dir level",
 	pkgdata: testutil.PackageData["base-files"],
@@ -117,6 +162,7 @@ var extractTests = []extractTest{{
 		"/etc/dpkg/":    "dir 0755",
 		"/etc/default/": "dir 0755",
 	},
+	notCreated: []string{"/etc/"},
 }, {
 	summary: "Globbing for files with multiple levels at once",
 	pkgdata: testutil.PackageData["base-files"],
@@ -136,6 +182,7 @@ var extractTests = []extractTest{{
 		"/etc/default/":            "dir 0755",
 		"/etc/debian_version":      "file 0644 cce26cfe",
 	},
+	notCreated: []string{"/etc/"},
 }, {
 	summary: "Globbing with reporting of globbed paths",
 	pkgdata: testutil.PackageData["base-files"],
@@ -159,6 +206,7 @@ var extractTests = []extractTest{{
 		"/etc/dp*/": []string{"/etc/dpkg/"},
 		"/etc/de**": []string{"/etc/debian_version", "/etc/default/"},
 	},
+	notCreated: []string{"/etc/"},
 }, {
 	summary: "Globbing must have matching source and target",
 	pkgdata: testutil.PackageData["base-files"],
@@ -266,6 +314,7 @@ var extractTests = []extractTest{{
 		"/usr/bin/": "dir 0755",
 		"/tmp/":     "dir 01777",
 	},
+	notCreated: []string{},
 }, {
 	summary: "Optional entries mixed in cannot be missing",
 	pkgdata: testutil.PackageData["base-files"],
@@ -291,7 +340,20 @@ func (s *S) TestExtract(c *C) {
 		options := test.options
 		options.Package = "base-files"
 		options.TargetDir = dir
-		options.Creator = fsutil.NewCreator()
+		createdPaths := make(map[string]bool)
+		options.Create = func(o *fsutil.CreateOptions) error {
+			relPath := filepath.Clean("/" + strings.TrimPrefix(o.Path, dir))
+			if o.Mode&fs.ModeDir != 0 {
+				relPath = relPath + "/"
+			}
+			createdPaths[relPath] = true
+			_, err := fsutil.Create(o)
+			return err
+		}
+
+		if test.hackopt != nil {
+			test.hackopt(&options)
+		}
 
 		if test.globbed != nil {
 			options.Globbed = make(map[string][]string)
@@ -309,6 +371,18 @@ func (s *S) TestExtract(c *C) {
 			c.Assert(options.Globbed, DeepEquals, test.globbed)
 		}
 
+		if test.notCreated != nil {
+			notCreated := []string{}
+			for path := range test.result {
+				if !createdPaths[path] {
+					notCreated = append(notCreated, path)
+				}
+			}
+			sort.Strings(notCreated)
+			sort.Strings(test.notCreated)
+			c.Assert(notCreated, DeepEquals, test.notCreated)
+		}
+
 		result := testutil.TreeDump(dir)
 		c.Assert(result, DeepEquals, test.result)
 	}

internal/fsutil/create.go

@@ -21,26 +21,17 @@ type CreateOptions struct {
 	MakeParents bool
 }
 
-type Info struct {
+type Entry struct {
 	Path string
 	Mode fs.FileMode
 	Hash string
 	Size int
 	Link string
 }
 
-type Creator struct {
-	// Created keeps track of information about the filesystem entries created.
-	// If an entry is created several times it only tracks the latest one.
-	Created map[string]Info
-}
-
-func NewCreator() *Creator {
-	return &Creator{Created: make(map[string]Info)}
-}
-
-// Create creates a filesystem entry according to the provided options.
-func (c *Creator) Create(options *CreateOptions) error {
+// Create creates a filesystem entry according to the provided options and returns
+// the information about the created entry.
+func Create(options *CreateOptions) (*Entry, error) {
 	rp := &readerProxy{inner: options.Data, h: sha256.New()}
 	// Use the proxy instead of the raw Reader.
 	optsCopy := *options
@@ -50,7 +41,7 @@ func (c *Creator) Create(options *CreateOptions) error {
 	var err error
 	if o.MakeParents {
 		if err := os.MkdirAll(filepath.Dir(o.Path), 0755); err != nil {
-			return err
+			return nil, err
 		}
 	}
 	switch o.Mode & fs.ModeType {
@@ -64,18 +55,17 @@ func (c *Creator) Create(options *CreateOptions) error {
 		err = fmt.Errorf("unsupported file type: %s", o.Path)
 	}
 	if err != nil {
-		return err
+		return nil, err
 	}
 
-	info := Info{
+	entry := &Entry{
 		Path: o.Path,
 		Mode: o.Mode,
 		Hash: hex.EncodeToString(rp.h.Sum(nil)),
 		Size: rp.size,
 		Link: o.Link,
 	}
-	c.Created[o.Path] = info
-	return nil
+	return entry, nil
 }
 
 func createDir(o *CreateOptions) error {