Moved quiet flag into output

Author: Priya Wadhwa

README.md

@@ -111,6 +111,10 @@ To order files and packages by size (in descending order) when performing file s
 container-diff analyze remote://gcr.io/gcp-runtimes/multi-modified --type=pip --order
 ```
 
+To suppress output to stderr, add a `-q` or `--quiet` flag.
+```shell
+container-diff analyze file1.tar --type=file --quiet
+```
 
 ## Analysis Result Format
 

cmd/analyze.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/GoogleCloudPlatform/container-diff/cmd/util/output"
 	"github.com/GoogleCloudPlatform/container-diff/differs"
 	pkgutil "github.com/GoogleCloudPlatform/container-diff/pkg/util"
 	"github.com/sirupsen/logrus"
@@ -38,7 +39,6 @@ var analyzeCmd = &cobra.Command{
 		return nil
 	},
 	Run: func(cmd *cobra.Command, args []string) {
-		pkgutil.SetQuiet(quiet)
 		if err := analyzeImage(args[0], types); err != nil {
 			logrus.Error(err)
 			os.Exit(1)
@@ -87,7 +87,7 @@ func analyzeImage(imageName string, analyzerArgs []string) error {
 		return fmt.Errorf("Error performing image analysis: %s", err)
 	}
 
-	pkgutil.PrintToStdErr("Retrieving analyses")
+	output.PrintToStdErr("Retrieving analyses")
 	outputResults(analyses)
 
 	if save {
@@ -100,4 +100,5 @@ func analyzeImage(imageName string, analyzerArgs []string) error {
 func init() {
 	RootCmd.AddCommand(analyzeCmd)
 	addSharedFlags(analyzeCmd)
+	output.AddFlags(analyzeCmd)
 }

cmd/diff.go

@@ -22,6 +22,7 @@ import (
 	"os"
 	"sync"
 
+	"github.com/GoogleCloudPlatform/container-diff/cmd/util/output"
 	"github.com/GoogleCloudPlatform/container-diff/differs"
 	pkgutil "github.com/GoogleCloudPlatform/container-diff/pkg/util"
 	"github.com/GoogleCloudPlatform/container-diff/util"
@@ -42,7 +43,6 @@ var diffCmd = &cobra.Command{
 		return nil
 	},
 	Run: func(cmd *cobra.Command, args []string) {
-		pkgutil.SetQuiet(quiet)
 		if err := diffImages(args[0], args[1], types); err != nil {
 			logrus.Error(err)
 			os.Exit(1)
@@ -83,7 +83,7 @@ func diffImages(image1Arg, image2Arg string, diffArgs []string) error {
 	var wg sync.WaitGroup
 	wg.Add(2)
 
-	pkgutil.PrintToStdErr("Starting diff on images %s and %s, using differs: %s\n", image1Arg, image2Arg, diffArgs)
+	output.PrintToStdErr("Starting diff on images %s and %s, using differs: %s\n", image1Arg, image2Arg, diffArgs)
 
 	imageMap := map[string]*pkgutil.Image{
 		image1Arg: {},
@@ -113,7 +113,7 @@ func diffImages(image1Arg, image2Arg string, diffArgs []string) error {
 		defer pkgutil.CleanupImage(*imageMap[image2Arg])
 	}
 
-	pkgutil.PrintToStdErr("Computing diffs")
+	output.PrintToStdErr("Computing diffs")
 	req := differs.DiffRequest{
 		Image1:    *imageMap[image1Arg],
 		Image2:    *imageMap[image2Arg],
@@ -125,7 +125,7 @@ func diffImages(image1Arg, image2Arg string, diffArgs []string) error {
 	outputResults(diffs)
 
 	if filename != "" {
-		pkgutil.PrintToStdErr("Computing filename diffs")
+		output.PrintToStdErr("Computing filename diffs")
 		err := diffFile(imageMap[image1Arg], imageMap[image2Arg])
 		if err != nil {
 			return err
@@ -152,4 +152,5 @@ func init() {
 	diffCmd.Flags().StringVarP(&filename, "filename", "f", "", "Set this flag to the path of a file in both containers to view the diff of the file. Must be used with --types=file flag.")
 	RootCmd.AddCommand(diffCmd)
 	addSharedFlags(diffCmd)
+	output.AddFlags(diffCmd)
 }

cmd/root.go

@@ -39,7 +39,6 @@ var json bool
 var save bool
 var types diffTypes
 var noCache bool
-var quiet bool
 
 var LogLevel string
 
@@ -210,7 +209,6 @@ func (d *diffTypes) Type() string {
 
 func addSharedFlags(cmd *cobra.Command) {
 	cmd.Flags().BoolVarP(&json, "json", "j", false, "JSON Output defines if the diff should be returned in a human readable format (false) or a JSON (true).")
-	cmd.Flags().BoolVarP(&quiet, "quiet", "q", false, "Suppress output to stderr.")
 	cmd.Flags().VarP(&types, "type", "t", "This flag sets the list of analyzer types to use. Set it repeatedly to use multiple analyzers.")
 	cmd.Flags().BoolVarP(&save, "save", "s", false, "Set this flag to save rather than remove the final image filesystems on exit.")
 	cmd.Flags().BoolVarP(&util.SortSize, "order", "o", false, "Set this flag to sort any file/package results by descending size. Otherwise, they will be sorted by name.")

pkg/util/cmd_utils.go renamed to cmd/util/output/output.go

@@ -14,21 +14,24 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package util
+package output
 
 import (
 	"fmt"
+	"github.com/spf13/cobra"
 	"os"
 )
 
-var quiet = false
+var quiet bool
 
+// PrintToStdErr prints to stderr if quiet flag isn't enabled
 func PrintToStdErr(output string, vars ...interface{}) {
 	if !quiet {
 		fmt.Fprintf(os.Stderr, output, vars...)
 	}
 }
 
-func SetQuiet(q bool) {
-	quiet = q
+// AddFlags adds quiet flag to suppress output to stderr
+func AddFlags(cmd *cobra.Command) {
+	cmd.Flags().BoolVarP(&quiet, "quiet", "q", false, "Suppress output to stderr.")
 }

pkg/util/image_prep_utils.go

@@ -25,6 +25,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/GoogleCloudPlatform/container-diff/cmd/util/output"
 	"github.com/GoogleCloudPlatform/container-diff/pkg/cache"
 	"github.com/containers/image/docker"
 	"github.com/containers/image/manifest"
@@ -99,7 +100,7 @@ type ConfigSchema struct {
 }
 
 func getImage(p Prepper) (Image, error) {
-	PrintToStdErr("Retrieving image %s from source %s\n", p.GetSource(), p.Name())
+	output.PrintToStdErr("Retrieving image %s from source %s\n", p.GetSource(), p.Name())
 	imgPath, err := p.GetFileSystem()
 	if err != nil {
 		return Image{}, err