implement a text presenter

Signed-off-by: Alfredo Deza <adeza@anchore.com>

imgbom/presenter/text/presenter.go

@@ -0,0 +1,56 @@
+package text
+
+import (
+	"fmt"
+	"io"
+	"text/tabwriter"
+
+	"github.com/anchore/imgbom/imgbom/pkg"
+	stereoscopeImg "github.com/anchore/stereoscope/pkg/image"
+)
+
+// Presenter holds the Present method to produce output
+type Presenter struct{}
+
+// NewPresenter is a constructor for a Presenter
+func NewPresenter() *Presenter {
+	return &Presenter{}
+}
+
+// Present is a method that is in charge of writing to an output buffer
+func (pres *Presenter) Present(output io.Writer, img *stereoscopeImg.Image, catalog *pkg.Catalog) error {
+	tags := make([]string, len(img.Metadata.Tags))
+	for idx, tag := range img.Metadata.Tags {
+		tags[idx] = tag.String()
+	}
+
+	// init the tabular writer
+	w := new(tabwriter.Writer)
+	w.Init(output, 0, 8, 0, '\t', tabwriter.AlignRight)
+
+	fmt.Fprintln(w, "[Image]")
+
+	for idx, l := range img.Layers {
+		fmt.Fprintln(w, " Layer:\t", idx)
+		fmt.Fprintln(w, " Digest:\t", l.Metadata.Digest)
+		fmt.Fprintln(w, " Size:\t", l.Metadata.Size)
+		fmt.Fprintln(w, " MediaType:\t", l.Metadata.MediaType)
+		fmt.Fprintln(w)
+		w.Flush()
+	}
+
+	// populate artifacts...
+	for p := range catalog.Enumerate() {
+		fmt.Fprintln(w, fmt.Sprintf("[%s]", p.Name))
+		fmt.Fprintln(w, " Version:\t", p.Version)
+		fmt.Fprintln(w, " Type:\t", p.Type.String())
+		if p.Metadata != nil {
+			fmt.Fprintf(w, " Metadata:\t%+v\n", p.Metadata)
+		}
+		fmt.Fprintln(w, " Found by:\t", p.FoundBy)
+		fmt.Fprintln(w)
+		w.Flush()
+	}
+
+	return nil
+}

imgbom/presenter/text/presenter_test.go

@@ -0,0 +1,74 @@
+package text
+
+import (
+	"bytes"
+	"flag"
+	"testing"
+
+	"github.com/anchore/go-testutils"
+	"github.com/anchore/imgbom/imgbom/pkg"
+	"github.com/anchore/stereoscope/pkg/file"
+	"github.com/sergi/go-diff/diffmatchpatch"
+)
+
+var update = flag.Bool("update", false, "update the *.golden files for json presenters")
+
+type PackageInfo struct {
+	Name    string
+	Version string
+}
+
+func TestTextPresenter(t *testing.T) {
+	pres := NewPresenter()
+	var buffer bytes.Buffer
+
+	catalog := pkg.NewCatalog()
+	img, cleanup := testutils.GetFixtureImage(t, "docker-archive", "image-simple")
+	defer cleanup()
+
+	// populate catalog with test data
+	catalog.Add(pkg.Package{
+		Name:    "package-1",
+		Version: "1.0.1",
+		Source: []file.Reference{
+			*img.SquashedTree().File("/somefile-1.txt"),
+		},
+		FoundBy: "dpkg",
+		Type:    pkg.DebPkg,
+	})
+	catalog.Add(pkg.Package{
+		Name:    "package-2",
+		Version: "2.0.1",
+		Source: []file.Reference{
+			*img.SquashedTree().File("/somefile-2.txt"),
+		},
+		FoundBy:  "dpkg",
+		Metadata: PackageInfo{Name: "package-2", Version: "1.0.2"},
+		Type:     pkg.DebPkg,
+	})
+
+	// stub out all the digests so that they don't affect tests comparisons
+	// TODO: update with go-testutils feature when issue #1 is resolved
+	for _, l := range img.Layers {
+		l.Metadata.Digest = "sha256:ad8ecdc058976c07e7e347cb89fa9ad86a294b5ceaae6d09713fb035f84115abf3c4a2388a4af3aa60f13b94f4c6846930bdf53"
+	}
+
+	// run presenter
+	err := pres.Present(&buffer, img, catalog)
+	if err != nil {
+		t.Fatal(err)
+	}
+	actual := buffer.Bytes()
+	if *update {
+		testutils.UpdateGoldenFileContents(t, actual)
+	}
+
+	var expected = testutils.GetGoldenFileContents(t)
+
+	if !bytes.Equal(expected, actual) {
+		dmp := diffmatchpatch.New()
+		diffs := dmp.DiffMain(string(actual), string(expected), true)
+		t.Errorf("mismatched output:\n%s", dmp.DiffPrettyText(diffs))
+	}
+
+}

imgbom/presenter/text/test-fixtures/snapshot/TestTextPresenter.golden

@@ -1,28 +1,22 @@
 [Image]
  Layer:		 0
- Digest:	 sha256:056c0789fa9ad629ceae6d09713fb035f84115af3c4a88a43aa60f13bc683053
+ Digest:	 sha256:ad8ecdc058976c07e7e347cb89fa9ad86a294b5ceaae6d09713fb035f84115abf3c4a2388a4af3aa60f13b94f4c6846930bdf53
  Size:		 22
  MediaType:	 application/vnd.docker.image.rootfs.diff.tar.gzip
 
  Layer:		 1
- Digest:	 sha256:b461c48116592c570a66fed71d5b09662a8172e168b7938cf317af47872cdc9b
+ Digest:	 sha256:ad8ecdc058976c07e7e347cb89fa9ad86a294b5ceaae6d09713fb035f84115abf3c4a2388a4af3aa60f13b94f4c6846930bdf53
  Size:		 16
  MediaType:	 application/vnd.docker.image.rootfs.diff.tar.gzip
 
- Layer:		 2
- Digest:	 sha256:00b80053e05c01da485015610d288ce3185fac00d251e2ada02b45a7a7c5f589
- Size:		 27
- MediaType:	 application/vnd.docker.image.rootfs.diff.tar.gzip
-
 [package-1]
  Version:	 1.0.1
  Type:		 deb
- Metadata:	 <nil>
  Found by:	 dpkg
 
 [package-2]
  Version:	 2.0.1
  Type:		 deb
- Metadata:	 {package-2 1.0.2}
+ Metadata:	{Name:package-2 Version:1.0.2}
  Found by:	 dpkg