Add test for resolver and fix implementation

pkg/attestation/resolvers/txt/resolver.go

@@ -3,6 +3,7 @@ package txt
 import (
 	"bufio"
 	"io"
+	"strings"
 
 	"github.com/package-url/packageurl-go"
 
@@ -26,9 +27,24 @@ func (r *Resolver) Resolve(rc io.Reader) ([]attestation.Attestation, error) {
 		}
 		atts = append(atts, attestation.Attestation{
 			PURL: purl,
-			Type: attestation.SBOM,
+			Type: getType(purl),
 		})
 	}
 
 	return atts, nil
 }
+
+func getType(p packageurl.PackageURL) attestation.Type {
+	if attType, ok := p.Qualifiers.Map()["attestation_type"]; ok {
+		switch strings.ToLower(attType) {
+		case "provenance":
+			return attestation.Provenance
+		case "sbom":
+			return attestation.SBOM
+		default:
+			return attestation.Unknown
+		}
+	}
+
+	return attestation.Unknown
+}

pkg/attestation/resolvers/txt/resolver_test.go

@@ -0,0 +1,38 @@
+package txt_test
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/philips-labs/fatt/pkg/attestation/resolvers/txt"
+)
+
+func TestResolve(t *testing.T) {
+	assert := assert.New(t)
+
+	purlsFile := `pkg:docker/philips-labs/fatt@sha256:6cc65b2c82c2baa3391890abb8ab741efbcbc87baff3b06d5797afacb314ddd9?repository_url=ghcr.io&attestation_type=sbom
+pkg:docker/philips-labs/fatt@sha256:6cc65b2c82c2baa3391890abb8ab741efbcbc87baff3b06d5797afacb314ddd9?repository_url=ghcr.io&attestation_type=provenance
+pkg:docker/philips-labs/fatt@sha256:6cc65b2c82c2baa3391890abb8ab741efbcbc87baff3b06d5797afacb314ddd9?repository_url=ghcr.io
+pkg:nuget/philips-labs/fatt@sha256:6cc65b2c82c2baa3391890abb8ab741efbcbc87baff3b06d5797afacb314ddd9?repository_url=nuget.org&attestation_type=provenance
+pkg:nuget/philips-labs/fatt@sha256:823413cc65b2c82c2baa3391890abb8ab741e87baff3b06d5797afacb314ddd9?repository_url=nuget.org&attestation_type=sbom`
+
+	r := &txt.Resolver{}
+	atts, err := r.Resolve(strings.NewReader(purlsFile))
+	assert.NoError(err)
+	assert.Len(atts, 5)
+
+	assert.Equal("SBOM", atts[0].Type.String())
+	assert.Equal("Provenance", atts[1].Type.String())
+	assert.Equal("Unknown", atts[2].Type.String())
+	assert.Equal("Provenance", atts[3].Type.String())
+	assert.Equal("SBOM", atts[4].Type.String())
+
+	purlsFile = `pkg:docker/philips-labs/fatt@sha256:6cc65b2c82c2baa3391890abb8ab741efbcbc87baff3b06d5797afacb314ddd9?repository_url=ghcr.io&attestation_type=sbom
+	ghcr.io/philips-labs/fatt@sha256:6cc65b2c82c2baa3391890abb8ab741efbcbc87baff3b06d5797afacb314ddd9`
+	atts, err = r.Resolve(strings.NewReader(purlsFile))
+	assert.Error(err)
+	assert.EqualError(err, "scheme is missing")
+	assert.Len(atts, 0)
+}