Rename GetCertificate to Certificate

Getters should not be prefixed with `Get` per standard Go practices (cited by Effective Go). This PR renames `GetCertificate` to `Certificate`.

Signed-off-by: Cody Soyland <codysoyland@github.com>

pkg/bundle/bundle_test.go

@@ -814,7 +814,7 @@ func TestVerificationContent(t *testing.T) {
 			}
 			require.NoError(t, gotErr)
 			if tt.wantCertificate {
-				require.NotNil(t, got.GetCertificate())
+				require.NotNil(t, got.Certificate())
 				return
 			}
 			if tt.wantPublicKey {

pkg/bundle/verification_content.go

@@ -52,7 +52,7 @@ func (c *Certificate) ValidAtTime(t time.Time, _ root.TrustedMaterial) bool {
 	return !(c.certificate.NotAfter.Before(t) || c.certificate.NotBefore.After(t))
 }
 
-func (c *Certificate) GetCertificate() *x509.Certificate {
+func (c *Certificate) Certificate() *x509.Certificate {
 	return c.certificate
 }
 
@@ -83,7 +83,7 @@ func (pk *PublicKey) ValidAtTime(t time.Time, tm root.TrustedMaterial) bool {
 	return verifier.ValidAtTime(t)
 }
 
-func (pk *PublicKey) GetCertificate() *x509.Certificate {
+func (pk *PublicKey) Certificate() *x509.Certificate {
 	return nil
 }
 

pkg/fulcio/certificate/summarize_test.go

@@ -30,7 +30,7 @@ func TestSummarizeCertificateWithActionsBundle(t *testing.T) {
 		t.Fatalf("failed to get verification content: %v", err)
 	}
 
-	leaf := vc.GetCertificate()
+	leaf := vc.Certificate()
 
 	if leaf == nil {
 		t.Fatalf("expected verification content to be a certificate chain")
@@ -79,7 +79,7 @@ func TestSummarizeCertificateWithOauthBundle(t *testing.T) {
 		t.Fatalf("failed to get verification content: %v", err)
 	}
 
-	leaf := vc.GetCertificate()
+	leaf := vc.Certificate()
 
 	if leaf == nil {
 		t.Fatalf("expected verification content to be a certificate chain")
@@ -108,7 +108,7 @@ func TestSummarizeCertificateWithOtherNameSAN(t *testing.T) {
 		t.Fatalf("failed to get verification content: %v", err)
 	}
 
-	leaf := vc.GetCertificate()
+	leaf := vc.Certificate()
 
 	if leaf == nil {
 		t.Fatalf("expected verification content to be a certificate chain")

pkg/verify/interface.go

@@ -63,7 +63,7 @@ type SignedEntity interface {
 type VerificationContent interface {
 	CompareKey(any, root.TrustedMaterial) bool
 	ValidAtTime(time.Time, root.TrustedMaterial) bool
-	GetCertificate() *x509.Certificate
+	Certificate() *x509.Certificate
 	HasPublicKey() (PublicKeyProvider, bool)
 }
 

pkg/verify/signature.go

@@ -94,7 +94,7 @@ func VerifySignatureWithArtifactDigest(sigContent SignatureContent, verification
 }
 
 func getSignatureVerifier(verificationContent VerificationContent, tm root.TrustedMaterial) (signature.Verifier, error) {
-	if leafCert := verificationContent.GetCertificate(); leafCert != nil {
+	if leafCert := verificationContent.Certificate(); leafCert != nil {
 		// TODO: Inspect certificate's SignatureAlgorithm to determine hash function
 		return signature.LoadVerifier(leafCert.PublicKey, crypto.SHA256)
 	} else if pk, ok := verificationContent.HasPublicKey(); ok {

pkg/verify/signed_entity.go

@@ -508,7 +508,7 @@ func (v *SignedEntityVerifier) Verify(entity SignedEntity, pb PolicyBuilder) (*V
 
 	// If the bundle was signed with a long-lived key, and does not have a Fulcio certificate,
 	// then skip the certificate verification steps
-	if leafCert := verificationContent.GetCertificate(); leafCert != nil {
+	if leafCert := verificationContent.Certificate(); leafCert != nil {
 		if policy.WeExpectSigningKey() {
 			return nil, errors.New("expected key signature, not certificate")
 		}
@@ -719,7 +719,7 @@ func (v *SignedEntityVerifier) VerifyObserverTimestamps(entity SignedEntity, log
 			return nil, err
 		}
 
-		if leafCert := verificationContent.GetCertificate(); leafCert != nil {
+		if leafCert := verificationContent.Certificate(); leafCert != nil {
 			verifiedTimestamps = append(verifiedTimestamps, TimestampVerificationResult{Type: "LeafCert.NotBefore", URI: "", Timestamp: leafCert.NotBefore})
 		} else {
 			// no cert? use current time