feat: better error handling and warning propagation (#31)

.github/workflows/test.yaml

@@ -27,7 +27,7 @@ jobs:
       - name: Display Go version
         run: go version
       - name: Run tests
-        run: sudo go test ./...
+        run: sudo go test -v ./... -test.count=5
       - name: Run simple example
         run: sudo go run examples/simple/main.go
       - name: Run activation example

client_test.go

@@ -26,10 +26,11 @@ import (
 )
 
 func TestLVs(t *testing.T) {
-	SkipOrFailTestIfNotRoot(t)
-	ctx := WithCustomEnvironment(context.Background(), map[string]string{})
+	t.Parallel()
 	slog.SetDefault(slog.New(NewContextPropagatingSlogHandler(NewTestingHandler(t))))
 	slog.SetLogLoggerLevel(slog.LevelDebug)
+
+	SkipOrFailTestIfNotRoot(t)
 	for i, tc := range []test{
 		{
 			LoopDevices: []Size{
@@ -79,9 +80,12 @@ func TestLVs(t *testing.T) {
 		},
 	} {
 		t.Run(fmt.Sprintf("[%v]%s", i, tc.String()), func(t *testing.T) {
-			SkipOrFailTestIfNotRoot(t)
+			t.Parallel()
+			ctx := WithCustomEnvironment(context.Background(), map[string]string{})
 			ctx, cancel := context.WithCancel(ctx)
 			defer cancel()
+
+			SkipOrFailTestIfNotRoot(t)
 			clnt := GetTestClient(ctx)
 			infra := tc.SetupDevicesAndVolumeGroup(t)
 
@@ -118,12 +122,19 @@ func TestLVs(t *testing.T) {
 				t.Fatalf("Expected volume group %s, got %s", infra.volumeGroup.Name, vg.Name)
 			}
 
-			pvs, err := clnt.PVs(ctx, infra.volumeGroup.Name)
-			if err != nil {
-				t.Fatal(err)
+			var pvs []*PhysicalVolume
+			success := false
+			for attempt := 0; attempt < 3; attempt++ {
+				if pvs, err = clnt.PVs(ctx, infra.volumeGroup.Name); err != nil {
+					t.Logf("failed to get physical volumes: %s", err)
+				}
+				if len(pvs) != len(infra.loopDevices) {
+					t.Logf("%s expected %d physical volumes, got %d", t.Name(), len(infra.loopDevices), len(pvs))
+				}
+				success = true
 			}
-			if len(pvs) != len(infra.loopDevices) {
-				t.Fatalf("Expected %d physical volumes, got %d", len(infra.loopDevices), len(pvs))
+			if !success {
+				t.Fatalf("failed to get physical volumes: %s", err)
 			}
 
 			for _, pv := range pvs {

config_test.go

@@ -125,6 +125,7 @@ func Test_DecodeConfig(t *testing.T) {
 }
 
 func Test_EncodeDecode(t *testing.T) {
+	t.Parallel()
 	SkipOrFailTestIfNotRoot(t)
 	slog.SetDefault(slog.New(NewContextPropagatingSlogHandler(NewTestingHandler(t))))
 	slog.SetLogLoggerLevel(slog.LevelDebug)
@@ -145,7 +146,7 @@ func Test_EncodeDecode(t *testing.T) {
 		t.Fatalf("profile dir is empty even though that was not expected")
 	}
 
-	profileName := "lvm2go-test"
+	profileName := "lvm2go-test-encode-decode"
 
 	testFile, err := os.OpenFile(filepath.Join(c.Config.ProfileDir, fmt.Sprintf("%s.profile", profileName)), os.O_CREATE|os.O_RDWR, 0600)
 	if err != nil {
@@ -167,7 +168,7 @@ func Test_EncodeDecode(t *testing.T) {
 	c = &structConfig{}
 	if err := clnt.ReadAndDecodeConfig(ctx, c, ConfigTypeFull, Profile(profileName)); err == nil {
 		t.Fatalf("expected error due no customizable profile")
-	} else if !IsLVMErrConfigurationSectionNotCustomizableByProfile(err) {
+	} else if !IsConfigurationSectionNotCustomizableByProfile(err) {
 		t.Fatalf("expected error due no customizable profile, but got %v", err)
 	}
 }
@@ -252,13 +253,14 @@ func TestGetProfilePath(t *testing.T) {
 }
 
 func TestProfile(t *testing.T) {
+	t.Parallel()
 	SkipOrFailTestIfNotRoot(t)
 	slog.SetDefault(slog.New(NewContextPropagatingSlogHandler(NewTestingHandler(t))))
 	slog.SetLogLoggerLevel(slog.LevelDebug)
 	ctx := context.Background()
 	clnt := GetTestClient(ctx)
 
-	profile := Profile("lvm2go-test")
+	profile := Profile("lvm2go-test-profile")
 
 	type structConfig struct {
 		Config struct {
@@ -283,7 +285,7 @@ func TestProfile(t *testing.T) {
 	}
 
 	err = clnt.ReadAndDecodeConfig(ctx, c, ConfigTypeFull, profile)
-	if !IsLVMErrConfigurationSectionNotCustomizableByProfile(err) {
+	if !IsConfigurationSectionNotCustomizableByProfile(err) {
 		t.Fatalf("expected error due no customizable profile, but got %v", err)
 	}
 }

exit_code_error.go

@@ -17,9 +17,7 @@
 package lvm2go
 
 import (
-	"bytes"
 	"errors"
-	"fmt"
 )
 
 // AsExitCodeError returns the ExitCodeError from the error if it exists and a bool indicating if is an ExitCodeError or not.
@@ -35,42 +33,31 @@ func AsExitCodeError(err error) (ExitCodeError, bool) {
 type ExitCodeError interface {
 	error
 	ExitCode() int
-	Unwrap() error
 }
 
 // NewExitCodeError returns a new ExitCodeError with the provided error and stderr output.
-func NewExitCodeError(err error, stderr []byte) ExitCodeError {
-	return &exitCodeErr{
-		err:    err,
-		stderr: stderr,
+func NewExitCodeError(err error) ExitCodeError {
+	if err == nil {
+		return nil
 	}
+	return &exitCodeErr{error: err}
 }
 
 // exitCodeErr is an implementation of ExitCodeError storing the original error and the stderr output of the lvmBinaryPath command.
 // It also provides a POSIX exit code that can be used to determine the type of error from LVM.
 type exitCodeErr struct {
-	err    error
-	stderr []byte
-}
-
-func (e *exitCodeErr) Error() string {
-	if e.stderr != nil {
-		return fmt.Sprintf("%v: %v", e.err, string(bytes.TrimSpace(e.stderr)))
-	}
-	return e.err.Error()
+	error
 }
 
-func (e *exitCodeErr) Unwrap() error {
-	return e.err
-}
+var _ ExitCodeError = &exitCodeErr{}
 
 func (e *exitCodeErr) ExitCode() int {
 	type exitError interface {
 		ExitCode() int
 		error
 	}
 	var err exitError
-	if errors.As(e.err, &err) {
+	if errors.As(e.error, &err) {
 		return err.ExitCode()
 	}
 	return -1

losetup.go

@@ -285,24 +285,20 @@ func (dev *loopbackDevice) SetBackingFile(file string) error {
 		return ErrDeviceAlreadyClosed
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), dev.commandTimeout)
-	defer cancel()
-
 	if err := dev.setFile(file); err != nil {
 		return err
 	}
 
-	if _, err := os.Stat(dev.file); err == nil {
-		return fmt.Errorf("backing file %s already exists", dev.file)
-	} else if !os.IsNotExist(err) {
-		return fmt.Errorf("failed to check for backing file existence %s: %w", dev.file, err)
+	fd, err := os.OpenFile(dev.file, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
+	if err != nil {
+		return fmt.Errorf("failed to open or create backing file %s: %w", dev.file, err)
 	}
+	defer fd.Close()
 
-	args := []string{fmt.Sprintf("--size=%v", uint64(dev.size.Val)), dev.file}
-	out, err := exec.CommandContext(ctx, "truncate", args...).CombinedOutput()
-	if err != nil {
-		return fmt.Errorf("failed to truncate backing file: %w: %s", err, string(out))
+	if err := fd.Truncate(int64(dev.size.Val)); err != nil {
+		return fmt.Errorf("failed to truncate backing file %s to size %v: %w", dev.file, dev.size.Val, err)
 	}
+
 	return nil
 }
 

lvm_error.go

@@ -17,14 +17,21 @@
 package lvm2go
 
 import (
+	"fmt"
 	"regexp"
-	"slices"
 )
 
 var (
-	// NotFoundPattern is a regular expression that matches the error message when a volume group or logical volume is not found.
-	// The volume group might not be present or the logical volume might not be present in the volume group.
-	NotFoundPattern = regexp.MustCompile(`Volume group "(.*?)" not found|Failed to find logical volume "(.*?)"`)
+
+	// NotFoundPatterns are regular expressions that matches the error message when a device, volume group or logical volume is not found.
+
+	volumeGroupNotFoundPattern   = `Volume group "(.*?)" not found`
+	VolumeGroupNotFoundPattern   = regexp.MustCompile(volumeGroupNotFoundPattern)
+	logicalVolumeNotFoundPattern = `Failed to find logical volume "(.*?)"`
+	LogicalVolumeNotFoundPattern = regexp.MustCompile(logicalVolumeNotFoundPattern)
+	deviceNotFoundPattern        = `Couldn't find device with uuid (.{6}-.{4}-.{4}-.{4}-.{4}-.{4}-.{6})`
+	DeviceNotFoundPattern        = regexp.MustCompile(deviceNotFoundPattern)
+	NotFoundPattern              = regexp.MustCompile(fmt.Sprintf(`%s|%s|%s`, volumeGroupNotFoundPattern, logicalVolumeNotFoundPattern, deviceNotFoundPattern))
 
 	// NoSuchCommandPattern is a regular expression that matches the error message when a command is not found.
 	NoSuchCommandPattern = regexp.MustCompile(`no such command`)
@@ -66,71 +73,88 @@ var (
 // Example:
 //
 //	func IsLVMCustomError(err error) bool {
-//		return IsLVMError(err, regexp.MustCompile(`custom error pattern`), 5)
+//		return IsLVMError(err, regexp.MustCompile(`custom error pattern`))
 //	}
-func IsLVMError(err error, pattern *regexp.Regexp, validExitCodes ...int) bool {
+func IsLVMError(err error, pattern *regexp.Regexp) bool {
 	if err == nil {
 		return false
 	}
-	lvmErr, ok := AsExitCodeError(err)
-	if !ok || !slices.Contains(validExitCodes, lvmErr.ExitCode()) {
-		return false
+
+	if stdErr, ok := AsLVMStdErr(err); ok {
+		for _, line := range stdErr.Lines(true) {
+			if pattern.Match(line) {
+				return true
+			}
+		}
 	}
-	return pattern.Match([]byte(lvmErr.Error()))
+
+	return false
+}
+
+func IsNotFound(err error) bool {
+	return IsLVMError(err, NotFoundPattern)
+}
+
+func IsVolumeGroupNotFound(err error) bool {
+	return IsLVMError(err, VolumeGroupNotFoundPattern)
+}
+
+func IsLogicalVolumeNotFound(err error) bool {
+	return IsLVMError(err, LogicalVolumeNotFoundPattern)
 }
 
-func IsLVMErrNotFound(err error) bool {
-	return IsLVMError(err, NotFoundPattern, 5)
+func IsDeviceNotFound(err error) bool {
+	return IsLVMError(err, DeviceNotFoundPattern)
 }
 
-func IsLVMErrNoSuchCommand(err error) bool {
-	return IsLVMError(err, NoSuchCommandPattern, 2)
+func IsNoSuchCommand(err error) bool {
+	return IsLVMError(err, NoSuchCommandPattern)
 }
 
-func IsLVMErrMaximumLogicalVolumesReached(err error) bool {
-	return IsLVMError(err, MaximumNumberOfLogicalVolumesPattern, 5)
+func IsMaximumLogicalVolumesReached(err error) bool {
+	return IsLVMError(err, MaximumNumberOfLogicalVolumesPattern)
 }
 
-func IsLVMErrMaximumPhysicalVolumesReached(err error) bool {
-	return IsLVMError(err, MaximumNumberOfPhysicalVolumesPattern, 5)
+func IsMaximumPhysicalVolumesReached(err error) bool {
+	return IsLVMError(err, MaximumNumberOfPhysicalVolumesPattern)
 }
 
-func IsLVMErrVGImmutableDueToMissingPVs(err error) bool {
-	return IsLVMError(err, CannotChangeVGWhilePVsAreMissingPattern, 5)
+func IsVGImmutableDueToMissingPVs(err error) bool {
+	return IsLVMError(err, CannotChangeVGWhilePVsAreMissingPattern)
 }
 
-func IsLVMCouldNotFindDeviceWithUUID(err error) bool {
-	return IsLVMError(err, CouldNotFindDeviceWithUUIDPattern, 5)
+func IsCouldNotFindDeviceWithUUID(err error) bool {
+	return IsLVMError(err, CouldNotFindDeviceWithUUIDPattern)
 }
 
-func IsLVMErrVGMissingPVs(err error) bool {
-	return IsLVMError(err, VGMissingPVsPattern, 5, 3)
+func IsVGMissingPVs(err error) bool {
+	return IsLVMError(err, VGMissingPVsPattern)
 }
 
-func LVMErrVGMissingPVsDetails(err error) (vg string, pv string, lastWrittenTo string, ok bool) {
+func VGMissingPVsDetails(err error) (vg string, pv string, lastWrittenTo string, ok bool) {
 	submatches := VGMissingPVsPattern.FindStringSubmatch(err.Error())
 	if submatches == nil {
 		return "", "", "", false
 	}
 	return submatches[1], submatches[2], submatches[3], true
 }
 
-func IsLVMPartialLVNeedsRepairOrRemove(err error) bool {
-	return IsLVMError(err, PartialLVNeedsRepairOrRemovePattern, 5)
+func IsPartialLVNeedsRepairOrRemove(err error) bool {
+	return IsLVMError(err, PartialLVNeedsRepairOrRemovePattern)
 }
 
-func IsLVMErrThereAreStillPartialLVs(err error) bool {
-	return IsLVMError(err, ThereAreStillPartialLVsPattern, 5)
+func IsThereAreStillPartialLVs(err error) bool {
+	return IsLVMError(err, ThereAreStillPartialLVsPattern)
 }
 
-func IsLVMErrNoDataToMove(err error) bool {
-	return IsLVMError(err, NoDataToMovePattern, 5)
+func IsNoDataToMove(err error) bool {
+	return IsLVMError(err, NoDataToMovePattern)
 }
 
-func IsLVMNoFreeExtents(err error) bool {
-	return IsLVMError(err, NoFreeExtentsPattern, 5)
+func IsNoFreeExtents(err error) bool {
+	return IsLVMError(err, NoFreeExtentsPattern)
 }
 
-func IsLVMErrConfigurationSectionNotCustomizableByProfile(err error) bool {
-	return IsLVMError(err, ConfigurationSectionNotCustomizableByProfilePattern, 5)
+func IsConfigurationSectionNotCustomizableByProfile(err error) bool {
+	return IsLVMError(err, ConfigurationSectionNotCustomizableByProfilePattern)
 }

lvmdevices_check.go

@@ -44,7 +44,7 @@ func (c *client) DevCheck(ctx context.Context, opts ...DevCheckOption) error {
 
 	return c.RunRaw(
 		ctx,
-		NoOpRawOutputProcessor(false),
+		NoOpRawOutputProcessor(),
 		append([]string{"lvmdevices", "--check"}, args.GetRaw()...)...,
 	)
 }

lvmdevices_modify.go

@@ -105,7 +105,7 @@ func (c *client) DevModify(ctx context.Context, opts ...DevModifyOption) error {
 
 	return c.RunRaw(
 		ctx,
-		NoOpRawOutputProcessor(false),
+		NoOpRawOutputProcessor(),
 		append([]string{"lvmdevices"}, args.GetRaw()...)...,
 	)
 }

lvmdevices_update.go

@@ -59,7 +59,7 @@ func (c *client) DevUpdate(ctx context.Context, opts ...DevUpdateOption) error {
 
 	return c.RunRaw(
 		ctx,
-		NoOpRawOutputProcessor(false),
+		NoOpRawOutputProcessor(),
 		append([]string{"lvmdevices", "--update"}, args.GetRaw()...)...,
 	)
 }

lvs.go

@@ -64,7 +64,7 @@ func (c *client) LVs(ctx context.Context, opts ...LVsOption) ([]*LogicalVolume,
 
 	err = c.RunLVMInto(ctx, res, append(args, argsFromOpts.GetRaw()...)...)
 
-	if IsLVMErrNotFound(err) {
+	if IsNotFound(err) {
 		return nil, nil
 	}