create the dpkg analyzer

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

imgbom/analyzer/dpkg/analyzer.go

@@ -0,0 +1,60 @@
+package dpkg
+
+import (
+	"strings"
+
+	"github.com/anchore/imgbom/imgbom/pkg"
+	"github.com/anchore/stereoscope/pkg/file"
+	"github.com/anchore/stereoscope/pkg/tree"
+)
+
+type Analyzer struct {
+	selectedFiles []file.Reference
+}
+
+func NewAnalyzer() *Analyzer {
+	return &Analyzer{}
+}
+
+func (a *Analyzer) SelectFiles(trees []*tree.FileTree) []file.Reference {
+	files := make([]file.Reference, 0)
+	for _, tree := range trees {
+		// TODO: extract into function/slice/etc
+		file := tree.File("/var/lib/dpkg/status")
+		if file != nil {
+			files = append(files, *file)
+		}
+	}
+
+	a.selectedFiles = files
+
+	return files
+}
+
+func (a *Analyzer) Analyze(contents map[file.Reference]string) ([]pkg.Package, error) {
+	packages := make([]pkg.Package, 0)
+	for _, reference := range a.selectedFiles {
+		content, ok := contents[reference]
+		if !ok {
+			// TODO: this needs handling
+			panic(reference)
+		}
+
+		entries, err := ParseEntries(strings.NewReader(content))
+		if err != nil {
+			// TODO: punt for now, we need to handle this
+			panic(err)
+		}
+		for _, entry := range entries {
+			packages = append(packages, pkg.Package{
+				Name:     entry.Package,
+				Version:  entry.Version,
+				Type:     pkg.DebPkg,
+				Source:   []file.Reference{reference},
+				Metadata: entry,
+			})
+		}
+
+	}
+	return packages, nil
+}