Add better error handling for filesystem

server/backup/backup_local.go

@@ -2,13 +2,13 @@ package backup
 
 import (
 	"errors"
-	"github.com/pterodactyl/wings/server/filesystem"
 	"io"
 	"os"
 
+	"github.com/pterodactyl/wings/server/filesystem"
+
 	"github.com/mholt/archiver/v3"
 	"github.com/pterodactyl/wings/remote"
-	"github.com/pterodactyl/wings/system"
 )
 
 type LocalBackup struct {
@@ -78,10 +78,6 @@ func (b *LocalBackup) Restore(_ io.Reader, callback RestoreCallback) error {
 		if f.IsDir() {
 			return nil
 		}
-		name, err := system.ExtractArchiveSourceName(f, "/")
-		if err != nil {
-			return err
-		}
-		return callback(name, f)
+		return callback(f.Name(), f)
 	})
 }

server/filesystem/compress.go

@@ -9,8 +9,8 @@ import (
 	"sync/atomic"
 	"time"
 
+	"emperror.dev/errors"
 	"github.com/mholt/archiver/v3"
-	"github.com/pterodactyl/wings/system"
 )
 
 // CompressFiles compresses all of the files matching the given paths in the
@@ -86,13 +86,13 @@ func (fs *Filesystem) SpaceAvailableForDecompression(dir string, file string) er
 	// Walk over the archive and figure out just how large the final output would be from unarchiving it.
 	err = archiver.Walk(source, func(f archiver.File) error {
 		if atomic.AddInt64(&size, f.Size())+dirSize > fs.MaxDisk() {
-			return &Error{code: ErrCodeDiskSpace}
+			return newFilesystemError(ErrCodeDiskSpace, nil)
 		}
 		return nil
 	})
 	if err != nil {
-		if strings.HasPrefix(err.Error(), "format ") {
-			return &Error{code: ErrCodeUnknownArchive}
+		if IsUnknownArchiveFormatError(err) {
+			return newFilesystemError(ErrCodeUnknownArchive, err)
 		}
 		return err
 	}
@@ -111,7 +111,7 @@ func (fs *Filesystem) DecompressFile(dir string, file string) error {
 	}
 	// Ensure that the source archive actually exists on the system.
 	if _, err := os.Stat(source); err != nil {
-		return err
+		return errors.WithStack(err)
 	}
 
 	// Walk all of the files in the archiver file and write them to the disk. If any
@@ -127,13 +127,13 @@ func (fs *Filesystem) DecompressFile(dir string, file string) error {
 			return nil
 		}
 		if err := fs.Writefile(p, f); err != nil {
-			return &Error{code: ErrCodeUnknownError, err: err, resolved: source}
+			return wrapError(err, source)
 		}
 		return nil
 	})
 	if err != nil {
-		if strings.HasPrefix(err.Error(), "format ") {
-			return &Error{code: ErrCodeUnknownArchive}
+		if IsUnknownArchiveFormatError(err) {
+			return newFilesystemError(ErrCodeUnknownArchive, err)
 		}
 		return err
 	}

server/filesystem/disk_space.go

@@ -1,13 +1,14 @@
 package filesystem
 
 import (
-	"emperror.dev/errors"
-	"github.com/apex/log"
-	"github.com/karrick/godirwalk"
 	"sync"
 	"sync/atomic"
 	"syscall"
 	"time"
+
+	"emperror.dev/errors"
+	"github.com/apex/log"
+	"github.com/karrick/godirwalk"
 )
 
 type SpaceCheckingOpts struct {
@@ -48,7 +49,7 @@ func (fs *Filesystem) SetDiskLimit(i int64) {
 // no space, rather than a boolean value.
 func (fs *Filesystem) HasSpaceErr(allowStaleValue bool) error {
 	if !fs.HasSpaceAvailable(allowStaleValue) {
-		return &Error{code: ErrCodeDiskSpace}
+		return newFilesystemError(ErrCodeDiskSpace, nil)
 	}
 	return nil
 }
@@ -200,16 +201,13 @@ func (fs *Filesystem) HasSpaceFor(size int64) error {
 	if fs.MaxDisk() == 0 {
 		return nil
 	}
-
 	s, err := fs.DiskUsage(true)
 	if err != nil {
 		return err
 	}
-
 	if (s + size) > fs.MaxDisk() {
-		return &Error{code: ErrCodeDiskSpace}
+		return newFilesystemError(ErrCodeDiskSpace, nil)
 	}
-
 	return nil
 }
 

server/filesystem/errors.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"emperror.dev/errors"
 	"github.com/apex/log"
@@ -34,6 +35,14 @@ type Error struct {
 	path string
 }
 
+// newFilesystemError returns a new error instance with a stack trace associated.
+func newFilesystemError(code ErrorCode, err error) error {
+	if err != nil {
+		return errors.WithStackDepth(&Error{code: code, err: err}, 1)
+	}
+	return errors.WithStackDepth(&Error{code: code}, 1)
+}
+
 // Code returns the ErrorCode for this specific error instance.
 func (e *Error) Code() ErrorCode {
 	return e.code
@@ -63,13 +72,13 @@ func (e *Error) Error() string {
 	case ErrCodeUnknownError:
 		fallthrough
 	default:
-		return fmt.Sprintf("filesystem: an error occurred: %s", e.Cause())
+		return fmt.Sprintf("filesystem: an error occurred: %s", e.Unwrap())
 	}
 }
 
-// Cause returns the underlying cause of this filesystem error. In some causes
+// Unwrap returns the underlying cause of this filesystem error. In some causes
 // there may not be a cause present, in which case nil will be returned.
-func (e *Error) Cause() error {
+func (e *Error) Unwrap() error {
 	return e.err
 }
 
@@ -113,20 +122,26 @@ func IsErrorCode(err error, code ErrorCode) bool {
 	return false
 }
 
-// NewBadPathResolution returns a new BadPathResolution error.
-func NewBadPathResolution(path string, resolved string) *Error {
-	return &Error{code: ErrCodePathResolution, path: path, resolved: resolved}
+// IsUnknownArchiveFormatError checks if the error is due to the archive being
+// in an unexpected file format.
+func IsUnknownArchiveFormatError(err error) bool {
+	if err != nil && strings.HasPrefix(err.Error(), "format ") {
+		return true
+	}
+	return false
 }
 
-// WrapError wraps the provided error as a Filesystem error and attaches the
+// NewBadPathResolution returns a new BadPathResolution error.
+func NewBadPathResolution(path string, resolved string) error {
+	return errors.WithStackDepth(&Error{code: ErrCodePathResolution, path: path, resolved: resolved}, 1)
+}
+
+// wrapError wraps the provided error as a Filesystem error and attaches the
 // provided resolved source to it. If the error is already a Filesystem error
 // no action is taken.
-func WrapError(err error, resolved string) *Error {
-	if err == nil {
-		return nil
+func wrapError(err error, resolved string) error {
+	if err == nil || IsFilesystemError(err) {
+		return err
 	}
-	if IsFilesystemError(err) {
-		return err.(*Error)
-	}
-	return &Error{code: ErrCodeUnknownError, err: err, resolved: resolved}
+	return errors.WithStackDepth(&Error{code: ErrCodeUnknownError, err: err, resolved: resolved}, 1)
 }

server/filesystem/errors_test.go

@@ -1,13 +1,45 @@
 package filesystem
 
 import (
-	. "github.com/franela/goblin"
+	"io"
 	"testing"
+
+	"emperror.dev/errors"
+	. "github.com/franela/goblin"
 )
 
+type stackTracer interface {
+	StackTrace() errors.StackTrace
+}
+
 func TestFilesystem_PathResolutionError(t *testing.T) {
 	g := Goblin(t)
 
+	g.Describe("NewFilesystemError", func() {
+		g.It("includes a stack trace for the error", func() {
+			err := newFilesystemError(ErrCodeUnknownError, nil)
+
+			_, ok := err.(stackTracer)
+			g.Assert(ok).IsTrue()
+		})
+
+		g.It("properly wraps the underlying error cause", func() {
+			underlying := io.EOF
+			err := newFilesystemError(ErrCodeUnknownError, underlying)
+
+			_, ok := err.(stackTracer)
+			g.Assert(ok).IsTrue()
+
+			_, ok = err.(*Error)
+			g.Assert(ok).IsFalse()
+
+			fserr, ok := errors.Unwrap(err).(*Error)
+			g.Assert(ok).IsTrue()
+			g.Assert(fserr.Unwrap()).IsNotNil()
+			g.Assert(fserr.Unwrap()).Equal(underlying)
+		})
+	})
+
 	g.Describe("NewBadPathResolutionError", func() {
 		g.It("is can detect itself as an error correctly", func() {
 			err := NewBadPathResolution("foo", "bar")
@@ -18,6 +50,7 @@ func TestFilesystem_PathResolutionError(t *testing.T) {
 
 		g.It("returns <empty> if no destination path is provided", func() {
 			err := NewBadPathResolution("foo", "")
+			g.Assert(err).IsNotNil()
 			g.Assert(err.Error()).Equal("filesystem: server path [foo] resolves to a location outside the server root: <empty>")
 		})
 	})

server/filesystem/filesystem.go

@@ -67,7 +67,7 @@ func (fs *Filesystem) File(p string) (*os.File, Stat, error) {
 		return nil, Stat{}, err
 	}
 	if st.IsDir() {
-		return nil, Stat{}, &Error{code: ErrCodeIsDirectory}
+		return nil, Stat{}, newFilesystemError(ErrCodeIsDirectory, nil)
 	}
 	f, err := os.Open(cleaned)
 	if err != nil {
@@ -144,7 +144,7 @@ func (fs *Filesystem) Writefile(p string, r io.Reader) error {
 		return errors.Wrap(err, "server/filesystem: writefile: failed to stat file")
 	} else if err == nil {
 		if stat.IsDir() {
-			return &Error{code: ErrCodeIsDirectory, resolved: cleaned}
+			return errors.WithStack(&Error{code: ErrCodeIsDirectory, resolved: cleaned})
 		}
 		currentSize = stat.Size()
 	}

server/filesystem/path.go

@@ -20,7 +20,7 @@ func (fs *Filesystem) IsIgnored(paths ...string) error {
 			return err
 		}
 		if fs.denylist.MatchesPath(sp) {
-			return &Error{code: ErrCodeDenylistFile, path: p, resolved: sp}
+			return errors.WithStack(&Error{code: ErrCodeDenylistFile, path: p, resolved: sp})
 		}
 	}
 	return nil

server/filesystem/path_test.go

@@ -2,11 +2,12 @@ package filesystem
 
 import (
 	"bytes"
-	"emperror.dev/errors"
-	. "github.com/franela/goblin"
 	"os"
 	"path/filepath"
 	"testing"
+
+	"emperror.dev/errors"
+	. "github.com/franela/goblin"
 )
 
 func TestFilesystem_Path(t *testing.T) {