Add option to output SBOM report to a file (#530)

* add output to file option

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* log errors on close of the report destination

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* remove file option from persistent args

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* update file option comments and logging

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* allow for multiple UI fallback options

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* update UI select signatures + tests

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

cmd/event_loop.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"errors"
+	"fmt"
 	"os"
 
 	"github.com/anchore/syft/internal/log"
@@ -14,11 +15,13 @@ import (
 // signal interrupts. Is responsible for handling each event relative to a given UI an to coordinate eventing until
 // an eventual graceful exit.
 // nolint:gocognit,funlen
-func eventLoop(workerErrs <-chan error, signals <-chan os.Signal, subscription *partybus.Subscription, ux ui.UI, cleanupFn func()) error {
+func eventLoop(workerErrs <-chan error, signals <-chan os.Signal, subscription *partybus.Subscription, cleanupFn func(), uxs ...ui.UI) error {
 	defer cleanupFn()
 	events := subscription.Events()
 	var err error
-	if ux, err = setupUI(subscription.Unsubscribe, ux); err != nil {
+	var ux ui.UI
+
+	if ux, err = setupUI(subscription.Unsubscribe, uxs...); err != nil {
 		return err
 	}
 
@@ -78,15 +81,18 @@ func eventLoop(workerErrs <-chan error, signals <-chan os.Signal, subscription *
 	return retErr
 }
 
-func setupUI(unsubscribe func() error, ux ui.UI) (ui.UI, error) {
+// setupUI takes one or more UIs that responds to events and takes a event bus unsubscribe function for use
+// during teardown. With the given UIs, the first UI which the ui.Setup() function does not return an error
+// will be utilized in execution. Providing a set of UIs allows for the caller to provide graceful fallbacks
+// when there are environmental problem (e.g. unable to setup a TUI with the current TTY).
+func setupUI(unsubscribe func() error, uis ...ui.UI) (ui.UI, error) {
+	for _, ux := range uis {
 		if err := ux.Setup(unsubscribe); err != nil {
-		// replace the existing UI with a (simpler) logger UI
-		ux = ui.NewLoggerUI()
-		if err := ux.Setup(unsubscribe); err != nil {
-			// something is very wrong, bail.
-			return ux, err
-		}
-		log.Errorf("unable to setup given UI, falling back to logger: %+v", err)
+			log.Warnf("unable to setup given UI, falling back to alternative UI: %+v", err)
+			continue
 		}
+
 		return ux, nil
+	}
+	return nil, fmt.Errorf("unable to setup any UI")
 }

cmd/event_loop_test.go

@@ -96,8 +96,8 @@ func Test_eventLoop_gracefulExit(t *testing.T) {
 				worker(),
 				signaler(),
 				subscription,
-				ux,
 				cleanupFn,
+				ux,
 			),
 		)
 
@@ -159,8 +159,8 @@ func Test_eventLoop_workerError(t *testing.T) {
 				worker(),
 				signaler(),
 				subscription,
-				ux,
 				cleanupFn,
+				ux,
 			),
 			workerErr,
 			"should have seen a worker error, but did not",
@@ -230,8 +230,8 @@ func Test_eventLoop_unsubscribeError(t *testing.T) {
 				worker(),
 				signaler(),
 				subscription,
-				ux,
 				cleanupFn,
+				ux,
 			),
 		)
 
@@ -300,8 +300,8 @@ func Test_eventLoop_handlerError(t *testing.T) {
 				worker(),
 				signaler(),
 				subscription,
-				ux,
 				cleanupFn,
+				ux,
 			),
 			finalEvent.Error,
 			"should have seen a event error, but did not",
@@ -355,8 +355,8 @@ func Test_eventLoop_signalsStopExecution(t *testing.T) {
 				worker(),
 				signaler(),
 				subscription,
-				ux,
 				cleanupFn,
+				ux,
 			),
 		)
 
@@ -425,8 +425,8 @@ func Test_eventLoop_uiTeardownError(t *testing.T) {
 				worker(),
 				signaler(),
 				subscription,
-				ux,
 				cleanupFn,
+				ux,
 			),
 			teardownError,
 			"should have seen a UI teardown error, but did not",

cmd/packages.go

@@ -113,6 +113,11 @@ func setPackageFlags(flags *pflag.FlagSet) {
 		fmt.Sprintf("report output formatter, options=%v", packages.AllPresenters),
 	)
 
+	flags.StringP(
+		"file", "", "",
+		"file to write the report output to (default is STDOUT)",
+	)
+
 	///////// Upload options //////////////////////////////////////////////////////////
 	flags.StringP(
 		"host", "H", "",
@@ -156,6 +161,10 @@ func bindPackagesConfigOptions(flags *pflag.FlagSet) error {
 		return err
 	}
 
+	if err := viper.BindPFlag("file", flags.Lookup("file")); err != nil {
+		return err
+	}
+
 	///////// Upload options //////////////////////////////////////////////////////////
 
 	if err := viper.BindPFlag("anchore.host", flags.Lookup("host")); err != nil {
@@ -188,12 +197,24 @@ func bindPackagesConfigOptions(flags *pflag.FlagSet) error {
 func packagesExec(_ *cobra.Command, args []string) error {
 	// could be an image or a directory, with or without a scheme
 	userInput := args[0]
+
+	reporter, closer, err := reportWriter()
+	defer func() {
+		if err := closer(); err != nil {
+			log.Warnf("unable to write to report destination: %+v", err)
+		}
+	}()
+
+	if err != nil {
+		return err
+	}
+
 	return eventLoop(
 		packagesExecWorker(userInput),
 		setupSignals(),
 		eventSubscription,
-		ui.Select(appConfig.CliOptions.Verbosity > 0, appConfig.Quiet),
 		stereoscope.Cleanup,
+		ui.Select(appConfig.CliOptions.Verbosity > 0, appConfig.Quiet, reporter)...,
 	)
 }
 

cmd/power_user.go

@@ -7,6 +7,7 @@ import (
 	"github.com/anchore/stereoscope"
 	"github.com/anchore/syft/internal"
 	"github.com/anchore/syft/internal/bus"
+	"github.com/anchore/syft/internal/log"
 	"github.com/anchore/syft/internal/presenter/poweruser"
 	"github.com/anchore/syft/internal/ui"
 	"github.com/anchore/syft/syft/event"
@@ -73,12 +74,24 @@ func init() {
 func powerUserExec(_ *cobra.Command, args []string) error {
 	// could be an image or a directory, with or without a scheme
 	userInput := args[0]
+
+	reporter, closer, err := reportWriter()
+	defer func() {
+		if err := closer(); err != nil {
+			log.Warnf("unable to write to report destination: %+v", err)
+		}
+	}()
+
+	if err != nil {
+		return err
+	}
+
 	return eventLoop(
 		powerUserExecWorker(userInput),
 		setupSignals(),
 		eventSubscription,
-		ui.Select(appConfig.CliOptions.Verbosity > 0, appConfig.Quiet),
 		stereoscope.Cleanup,
+		ui.Select(appConfig.CliOptions.Verbosity > 0, appConfig.Quiet, reporter)...,
 	)
 }
 

cmd/report_writer.go

@@ -0,0 +1,29 @@
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/anchore/syft/internal/log"
+)
+
+func reportWriter() (io.Writer, func() error, error) {
+	nop := func() error { return nil }
+
+	path := strings.TrimSpace(appConfig.File)
+	switch len(path) {
+	case 0:
+		return os.Stdout, nop, nil
+	default:
+		reportFile, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
+		if err != nil {
+			return nil, nop, fmt.Errorf("unable to create report file: %w", err)
+		}
+		return reportFile, func() error {
+			log.Infof("report written to file=%q", path)
+			return reportFile.Close()
+		}, nil
+	}
+}

internal/config/application.go

@@ -29,6 +29,7 @@ type parser interface {
 type Application struct {
 	ConfigPath         string             `yaml:",omitempty" json:"configPath"`                                                         // the location where the application config was read from (either from -c or discovered while loading)
 	Output             string             `yaml:"output" json:"output" mapstructure:"output"`                                           // -o, the Presenter hint string to use for report formatting
+	File               string             `yaml:"file" json:"file" mapstructure:"file"`                                                 // --file, the file to write report output to
 	Quiet              bool               `yaml:"quiet" json:"quiet" mapstructure:"quiet"`                                              // -q, indicates to not show any status output to stderr (ETUI or logging UI)
 	CheckForAppUpdate  bool               `yaml:"check-for-app-update" json:"check-for-app-update" mapstructure:"check-for-app-update"` // whether to check for an application update on start up or not
 	Anchore            anchore            `yaml:"anchore" json:"anchore" mapstructure:"anchore"`                                        // options for interacting with Anchore Engine/Enterprise

internal/presenter/poweruser/test-fixtures/snapshot/TestJSONPresenter.golden

@@ -168,6 +168,7 @@
   "configuration": {
    "configPath": "",
    "output": "",
+   "file": "",
    "quiet": false,
    "check-for-app-update": false,
    "anchore": {

internal/ui/ephemeral_terminal_ui.go

@@ -38,20 +38,23 @@ type ephemeralTerminalUI struct {
 	waitGroup    *sync.WaitGroup
 	frame        *frame.Frame
 	logBuffer    *bytes.Buffer
-	output      *os.File
+	uiOutput     *os.File
+	reportOutput io.Writer
 }
 
-func NewEphemeralTerminalUI() UI {
+// NewEphemeralTerminalUI writes all events to a TUI and writes the final report to the given writer.
+func NewEphemeralTerminalUI(reportWriter io.Writer) UI {
 	return &ephemeralTerminalUI{
 		handler:      ui.NewHandler(),
 		waitGroup:    &sync.WaitGroup{},
-		output:    os.Stderr,
+		uiOutput:     os.Stderr,
+		reportOutput: reportWriter,
 	}
 }
 
 func (h *ephemeralTerminalUI) Setup(unsubscribe func() error) error {
 	h.unsubscribe = unsubscribe
-	hideCursor(h.output)
+	hideCursor(h.uiOutput)
 
 	// prep the logger to not clobber the screen from now on (logrus only)
 	h.logBuffer = bytes.NewBufferString("")
@@ -81,7 +84,7 @@ func (h *ephemeralTerminalUI) Handle(event partybus.Event) error {
 		// are about to write bytes to stdout, so we should reset the terminal state first
 		h.closeScreen(false)
 
-		if err := handleCatalogerPresenterReady(event); err != nil {
+		if err := handleCatalogerPresenterReady(event, h.reportOutput); err != nil {
 			log.Errorf("unable to show %s event: %+v", event.Type, err)
 		}
 
@@ -95,7 +98,7 @@ func (h *ephemeralTerminalUI) openScreen() error {
 	config := frame.Config{
 		PositionPolicy: frame.PolicyFloatForward,
 		// only report output to stderr, reserve report output for stdout
-		Output: h.output,
+		Output: h.uiOutput,
 	}
 
 	fr, err := frame.New(config)
@@ -128,15 +131,15 @@ func (h *ephemeralTerminalUI) flushLog() {
 	logWrapper, ok := log.Log.(*logger.LogrusLogger)
 	if ok {
 		fmt.Fprint(logWrapper.Output, h.logBuffer.String())
-		logWrapper.Logger.SetOutput(h.output)
+		logWrapper.Logger.SetOutput(h.uiOutput)
 	} else {
-		fmt.Fprint(h.output, h.logBuffer.String())
+		fmt.Fprint(h.uiOutput, h.logBuffer.String())
 	}
 }
 
 func (h *ephemeralTerminalUI) Teardown(force bool) error {
 	h.closeScreen(force)
-	showCursor(h.output)
+	showCursor(h.uiOutput)
 	return nil
 }
 

internal/ui/event_handlers.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"os"
 	"sync"
 
 	"github.com/anchore/syft/internal"
@@ -17,14 +16,14 @@ import (
 
 // handleCatalogerPresenterReady is a UI function for processing the CatalogerFinished bus event, displaying the catalog
 // via the given presenter to stdout.
-func handleCatalogerPresenterReady(event partybus.Event) error {
+func handleCatalogerPresenterReady(event partybus.Event, reportOutput io.Writer) error {
 	// show the report to stdout
 	pres, err := syftEventParsers.ParsePresenterReady(event)
 	if err != nil {
 		return fmt.Errorf("bad CatalogerFinished event: %w", err)
 	}
 
-	if err := pres.Present(os.Stdout); err != nil {
+	if err := pres.Present(reportOutput); err != nil {
 		return fmt.Errorf("unable to show package catalog report: %w", err)
 	}
 	return nil

internal/ui/logger_ui.go

@@ -1,6 +1,8 @@
 package ui
 
 import (
+	"io"
+
 	"github.com/anchore/syft/internal/log"
 	syftEvent "github.com/anchore/syft/syft/event"
 	"github.com/wagoodman/go-partybus"
@@ -8,10 +10,14 @@ import (
 
 type loggerUI struct {
 	unsubscribe  func() error
+	reportOutput io.Writer
 }
 
-func NewLoggerUI() UI {
-	return &loggerUI{}
+// NewLoggerUI writes all events to the common application logger and writes the final report to the given writer.
+func NewLoggerUI(reportWriter io.Writer) UI {
+	return &loggerUI{
+		reportOutput: reportWriter,
+	}
 }
 
 func (l *loggerUI) Setup(unsubscribe func() error) error {
@@ -25,7 +31,7 @@ func (l loggerUI) Handle(event partybus.Event) error {
 		return nil
 	}
 
-	if err := handleCatalogerPresenterReady(event); err != nil {
+	if err := handleCatalogerPresenterReady(event, l.reportOutput); err != nil {
 		log.Warnf("unable to show catalog image finished event: %+v", err)
 	}
 

internal/ui/select.go

@@ -1,6 +1,7 @@
 package ui
 
 import (
+	"io"
 	"os"
 	"runtime"
 
@@ -10,20 +11,21 @@ import (
 // TODO: build tags to exclude options from windows
 
 // Select is responsible for determining the specific UI function given select user option, the current platform
-// config values, and environment status (such as a TTY being present).
-func Select(verbose, quiet bool) UI {
-	var ui UI
-
+// config values, and environment status (such as a TTY being present). The first UI in the returned slice of UIs
+// is intended to be used and the UIs that follow are meant to be attempted only in a fallback posture when there
+// are environmental problems (e.g. cannot write to the terminal). A writer is provided to capture the output of
+// the final SBOM report.
+func Select(verbose, quiet bool, reportWriter io.Writer) (uis []UI) {
 	isStdoutATty := terminal.IsTerminal(int(os.Stdout.Fd()))
 	isStderrATty := terminal.IsTerminal(int(os.Stderr.Fd()))
 	notATerminal := !isStderrATty && !isStdoutATty
 
 	switch {
 	case runtime.GOOS == "windows" || verbose || quiet || notATerminal || !isStderrATty:
-		ui = NewLoggerUI()
+		uis = append(uis, NewLoggerUI(reportWriter))
 	default:
-		ui = NewEphemeralTerminalUI()
+		uis = append(uis, NewEphemeralTerminalUI(reportWriter), NewLoggerUI(reportWriter))
 	}
 
-	return ui
+	return uis
 }