analyzer_test: Adding seams for testability

Signed-off-by: Simarpreet Singh <simar@linux.com>

Author: simar7

analyzer/analyzer.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"io"
 	"os"
-	"time"
 
 	"github.com/aquasecurity/fanal/utils"
 
@@ -33,6 +32,10 @@ var (
 	ErrNoPkgsDetected = xerrors.New("No packages detected")
 )
 
+type AnalyzerConfig struct {
+	Extractor extractor.Extractor
+}
+
 type OSAnalyzer interface {
 	Analyze(extractor.FileMap) (OS, error)
 	RequiredFiles() []string
@@ -113,28 +116,19 @@ func RequiredFilenames() []string {
 	return filenames
 }
 
-func Analyze(ctx context.Context, imageName string, opts ...types.DockerOption) (fileMap extractor.FileMap, err error) {
-	// default docker option
-	opt := types.DockerOption{
-		Timeout:  600 * time.Second,
-		SkipPing: true,
-	}
-	if len(opts) > 0 {
-		opt = opts[0]
-	}
-
-	e := docker.NewDockerExtractor(opt)
-	r, err := e.SaveLocalImage(ctx, imageName)
+// TODO: Remove opts as they're no longer needed
+func (ac AnalyzerConfig) Analyze(ctx context.Context, imageName string, opts ...types.DockerOption) (fileMap extractor.FileMap, err error) {
+	r, err := ac.Extractor.SaveLocalImage(ctx, imageName)
 	if err != nil {
 		// when no docker daemon is installed or no image exists in the local machine
-		fileMap, err = e.Extract(ctx, imageName, RequiredFilenames())
+		fileMap, err = ac.Extractor.Extract(ctx, imageName, RequiredFilenames())
 		if err != nil {
 			return nil, xerrors.Errorf("failed to extract files: %w", err)
 		}
 		return fileMap, nil
 	}
 
-	fileMap, err = e.ExtractFromFile(ctx, r, RequiredFilenames())
+	fileMap, err = ac.Extractor.ExtractFromFile(ctx, r, RequiredFilenames())
 	if err != nil {
 		return nil, xerrors.Errorf("failed to extract files from saved tar: %w", err)
 	}

analyzer/analyzer_test.go

@@ -0,0 +1,45 @@
+package analyzer
+
+import (
+	"context"
+	"io"
+	"testing"
+
+	"github.com/aquasecurity/fanal/extractor"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type mockDockerExtractor struct {
+	saveLocalImage  func(ctx context.Context, imageName string) (io.Reader, error)
+	extractFromFile func(ctx context.Context, r io.Reader, filenames []string) (extractor.FileMap, error)
+}
+
+func (mde mockDockerExtractor) Extract(ctx context.Context, imageName string, filenames []string) (extractor.FileMap, error) {
+	panic("implement me")
+}
+
+func (mde mockDockerExtractor) ExtractFromFile(ctx context.Context, r io.Reader, filenames []string) (extractor.FileMap, error) {
+	if mde.extractFromFile != nil {
+		return mde.extractFromFile(ctx, r, filenames)
+	}
+	return extractor.FileMap{}, nil
+}
+
+func (mde mockDockerExtractor) SaveLocalImage(ctx context.Context, imageName string) (io.Reader, error) {
+	if mde.saveLocalImage != nil {
+		return mde.saveLocalImage(ctx, imageName)
+	}
+	return nil, nil
+}
+
+func (mde mockDockerExtractor) ExtractFiles(layer io.Reader, filenames []string) (extractor.FileMap, extractor.OPQDirs, error) {
+	panic("implement me")
+}
+
+func TestAnalyze(t *testing.T) {
+	ac := AnalyzerConfig{Extractor: mockDockerExtractor{}}
+	fm, err := ac.Analyze(context.TODO(), "foo")
+	assert.NoError(t, err)
+	assert.NotNil(t, fm)
+}

extractor/docker/docker.go

@@ -60,19 +60,17 @@ type layer struct {
 	Content io.ReadCloser
 }
 
-type opqDirs []string
-
 type DockerExtractor struct {
 	Option types.DockerOption
 }
 
-func NewDockerExtractor(option types.DockerOption) DockerExtractor {
+func NewDockerExtractor(option types.DockerOption) extractor.Extractor {
 	RegisterRegistry(&gcr.GCR{})
 	RegisterRegistry(&ecr.ECR{})
 	return DockerExtractor{Option: option}
 }
 
-func applyLayers(layerPaths []string, filesInLayers map[string]extractor.FileMap, opqInLayers map[string]opqDirs) (extractor.FileMap, error) {
+func applyLayers(layerPaths []string, filesInLayers map[string]extractor.FileMap, opqInLayers map[string]extractor.OPQDirs) (extractor.FileMap, error) {
 	sep := "/"
 	nestedMap := nested.Nested{}
 	for _, layerPath := range layerPaths {
@@ -190,7 +188,8 @@ func (d DockerExtractor) Extract(ctx context.Context, imageName string, filename
 
 	ch := make(chan layer)
 	errCh := make(chan error)
-	layerIDs := []string{}
+	var layerIDs []string
+
 	for _, ref := range m.Manifest.Layers {
 		layerIDs = append(layerIDs, string(ref.Digest))
 		go func(d digest.Digest) {
@@ -203,6 +202,7 @@ func (d DockerExtractor) Extract(ctx context.Context, imageName string, filename
 					errCh <- xerrors.Errorf("failed to download the layer(%s): %w", d, err)
 					return
 				}
+
 				rc, err = cache.Set(string(d), rc)
 				if err != nil {
 					log.Print(err)
@@ -218,7 +218,7 @@ func (d DockerExtractor) Extract(ctx context.Context, imageName string, filename
 	}
 
 	filesInLayers := make(map[string]extractor.FileMap)
-	opqInLayers := make(map[string]opqDirs)
+	opqInLayers := make(map[string]extractor.OPQDirs)
 	for i := 0; i < len(m.Manifest.Layers); i++ {
 		var l layer
 		select {
@@ -262,7 +262,7 @@ func (d DockerExtractor) Extract(ctx context.Context, imageName string, filename
 func (d DockerExtractor) ExtractFromFile(ctx context.Context, r io.Reader, filenames []string) (extractor.FileMap, error) {
 	manifests := make([]manifest, 0)
 	filesInLayers := map[string]extractor.FileMap{}
-	opqInLayers := make(map[string]opqDirs)
+	opqInLayers := make(map[string]extractor.OPQDirs)
 
 	tarFiles := make(map[string][]byte)
 
@@ -330,9 +330,9 @@ func (d DockerExtractor) ExtractFromFile(ctx context.Context, r io.Reader, filen
 	return fileMap, nil
 }
 
-func (d DockerExtractor) ExtractFiles(layer io.Reader, filenames []string) (extractor.FileMap, opqDirs, error) {
+func (d DockerExtractor) ExtractFiles(layer io.Reader, filenames []string) (extractor.FileMap, extractor.OPQDirs, error) {
 	data := make(map[string][]byte)
-	opqDirs := opqDirs{}
+	opqDirs := extractor.OPQDirs{}
 
 	tr := tar.NewReader(layer)
 	for {

extractor/docker/docker_test.go

@@ -122,7 +122,7 @@ func TestExtractFiles(t *testing.T) {
 		file      string            // Test input file
 		filenames []string          // Target files
 		FileMap   extractor.FileMap // Expected output
-		opqDirs   opqDirs           // Expected output
+		opqDirs   OPQDirs           // Expected output
 		err       error             // Expected error to occur
 	}{
 		{
@@ -167,7 +167,7 @@ func TestExtractFiles(t *testing.T) {
 				t.Errorf("err: got %v, want %v", v.err, err)
 			}
 			if !reflect.DeepEqual(opqDirs, v.opqDirs) {
-				t.Errorf("opqDirs: got %v, want %v", opqDirs, v.opqDirs)
+				t.Errorf("OPQDirs: got %v, want %v", opqDirs, v.opqDirs)
 			}
 			if !reflect.DeepEqual(fm, v.FileMap) {
 				t.Errorf("FilesMap: got %v, want %v", fm, v.FileMap)

extractor/extractor.go

@@ -6,8 +6,11 @@ import (
 )
 
 type FileMap map[string][]byte
+type OPQDirs []string
 
 type Extractor interface {
 	Extract(ctx context.Context, imageName string, filenames []string) (FileMap, error)
 	ExtractFromFile(ctx context.Context, r io.Reader, filenames []string) (FileMap, error)
+	SaveLocalImage(ctx context.Context, imageName string) (io.Reader, error)
+	ExtractFiles(layer io.Reader, filenames []string) (FileMap, OPQDirs, error)
 }