Ignore extra layers for --layer

Author: Priya Wadhwa

cmd/root.go

@@ -210,7 +210,7 @@ func getImageForName(imageName string) (pkgutil.Image, error) {
 
 func includeLayers() bool {
 	for _, t := range types {
-		if t == "file-layer" {
+		if t == "layer" {
 			return true
 		}
 	}

differs/differs.go

@@ -42,14 +42,14 @@ type Analyzer interface {
 }
 
 var Analyzers = map[string]Analyzer{
-	"history":    HistoryAnalyzer{},
-	"metadata":   MetadataAnalyzer{},
-	"file":       FileAnalyzer{},
-	"file-layer": FileLayerAnalyzer{},
-	"apt":        AptAnalyzer{},
-	"rpm":        RPMAnalyzer{},
-	"pip":        PipAnalyzer{},
-	"node":       NodeAnalyzer{},
+	"history":  HistoryAnalyzer{},
+	"metadata": MetadataAnalyzer{},
+	"file":     FileAnalyzer{},
+	"layer":    FileLayerAnalyzer{},
+	"apt":      AptAnalyzer{},
+	"rpm":      RPMAnalyzer{},
+	"pip":      PipAnalyzer{},
+	"node":     NodeAnalyzer{},
 }
 
 func (req DiffRequest) GetDiff() (map[string]util.Result, error) {

differs/file_diff.go

@@ -19,8 +19,7 @@ package differs
 import (
 	pkgutil "github.com/GoogleContainerTools/container-diff/pkg/util"
 	"github.com/GoogleContainerTools/container-diff/util"
-	"io/ioutil"
-	"os"
+	"github.com/sirupsen/logrus"
 )
 
 type FileAnalyzer struct {
@@ -81,23 +80,10 @@ func (a FileLayerAnalyzer) Name() string {
 // FileDiff diffs two packages and compares their contents
 func (a FileLayerAnalyzer) Diff(image1, image2 pkgutil.Image) (util.Result, error) {
 	var dirDiffs []util.DirDiff
-	// This path to an empty dir will be used for diffing in cases
-	// where one image has more layers than the other
-	emptyPath, err := ioutil.TempDir("", "")
-	if err != nil {
-		return &util.MultipleDirDiffResult{}, err
-	}
-	defer os.RemoveAll(emptyPath)
 
 	// Go through each layer of the first image...
 	for index, layer := range image1.Layers {
-		// ...if there is no corresponding layer in the second image, diff with the empty dir
 		if index >= len(image2.Layers) {
-			diff, err := diffImageFiles(layer.FSPath, emptyPath)
-			if err != nil {
-				return &util.MultipleDirDiffResult{}, err
-			}
-			dirDiffs = append(dirDiffs, diff)
 			continue
 		}
 		// ...else, diff as usual
@@ -109,16 +95,12 @@ func (a FileLayerAnalyzer) Diff(image1, image2 pkgutil.Image) (util.Result, erro
 		dirDiffs = append(dirDiffs, diff)
 	}
 
-	// check if there are any additional layers in image2...
-	if len(image2.Layers) > len(image1.Layers) {
-		// ... and diff any additional layers with the empty dir
-		for index := len(image1.Layers); index < len(image2.Layers); index++ {
-			layer2 := image2.Layers[index]
-			diff, err := diffImageFiles(emptyPath, layer2.FSPath)
-			if err != nil {
-				return &util.MultipleDirDiffResult{}, err
-			}
-			dirDiffs = append(dirDiffs, diff)
+	// check if there are any additional layers in either image
+	if len(image1.Layers) != len(image2.Layers) {
+		if len(image1.Layers) > len(image2.Layers) {
+			logrus.Infof("%s has additional layers, please use container-diff analyze to view the files in these layers", image1.Source)
+		} else {
+			logrus.Infof("%s has additional layers, please use container-diff analyze to view the files in these layers", image2.Source)
 		}
 	}
 	return &util.MultipleDirDiffResult{
@@ -138,8 +120,7 @@ func (a FileLayerAnalyzer) Analyze(image pkgutil.Image) (util.Result, error) {
 		if err != nil {
 			return util.FileLayerAnalyzeResult{}, err
 		}
-		directoryEntry := pkgutil.GetDirectoryEntries(layerDir)
-		directoryEntries = append(directoryEntries, directoryEntry)
+		directoryEntries = append(directoryEntries, pkgutil.GetDirectoryEntries(layerDir))
 	}
 
 	return &util.FileLayerAnalyzeResult{

tests/file_layer_diff_expected.json

@@ -24,16 +24,6 @@
             }
           ],
           "Mods": null
-        },
-        {
-          "Adds": null,
-          "Dels": [
-            {
-              "Name": "/third",
-              "Size": 6
-            }
-          ],
-          "Mods": null
         }
       ]
     }

tests/integration_test.go

@@ -114,7 +114,7 @@ func TestDiffAndAnalysis(t *testing.T) {
 			subcommand:   "diff",
 			imageA:       diffLayerBase,
 			imageB:       diffLayerModifed,
-			differFlags:  []string{"--type=file-layer"},
+			differFlags:  []string{"--type=layer"},
 			expectedFile: "file_layer_diff_expected.json",
 		},
 		{
@@ -206,7 +206,7 @@ func TestDiffAndAnalysis(t *testing.T) {
 			description:  "file layer analysis",
 			subcommand:   "analyze",
 			imageA:       diffLayerBase,
-			differFlags:  []string{"--type=file-layer"},
+			differFlags:  []string{"--type=layer"},
 			expectedFile: "file_layer_analysis_expected.json",
 		},
 		{