Create interface for GRPC server which encompasses the GRPC HealthSer…

…ver (#1334)

Signed-off-by: Priya Wadhwa <priya@chainguard.dev>

pkg/server/grpc_server.go

@@ -22,6 +22,8 @@ import (
 	"errors"
 	"fmt"
 
+	health "google.golang.org/grpc/health/grpc_health_v1"
+
 	ctclient "github.com/google/certificate-transparency-go/client"
 	certauth "github.com/sigstore/fulcio/pkg/ca"
 	"github.com/sigstore/fulcio/pkg/challenges"
@@ -32,21 +34,17 @@ import (
 	"github.com/sigstore/fulcio/pkg/log"
 	"github.com/sigstore/sigstore/pkg/cryptoutils"
 	"google.golang.org/grpc/codes"
-	health "google.golang.org/grpc/health/grpc_health_v1"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/status"
 )
 
-type GRPCCAServer struct {
-	fulciogrpc.UnimplementedCAServer
+type GRPCCAServer interface {
+	fulciogrpc.CAServer
 	health.HealthServer
-	ct *ctclient.LogClient
-	ca certauth.CertificateAuthority
-	identity.IssuerPool
 }
 
-func NewGRPCCAServer(ct *ctclient.LogClient, ca certauth.CertificateAuthority, ip identity.IssuerPool) *GRPCCAServer {
-	return &GRPCCAServer{
+func NewGRPCCAServer(ct *ctclient.LogClient, ca certauth.CertificateAuthority, ip identity.IssuerPool) GRPCCAServer {
+	return &grpcaCAServer{
 		ct:         ct,
 		ca:         ca,
 		IssuerPool: ip,
@@ -57,7 +55,14 @@ const (
 	MetadataOIDCTokenKey = "oidcidentitytoken"
 )
 
-func (g *GRPCCAServer) CreateSigningCertificate(ctx context.Context, request *fulciogrpc.CreateSigningCertificateRequest) (*fulciogrpc.SigningCertificate, error) {
+type grpcaCAServer struct {
+	fulciogrpc.UnimplementedCAServer
+	ct *ctclient.LogClient
+	ca certauth.CertificateAuthority
+	identity.IssuerPool
+}
+
+func (g *grpcaCAServer) CreateSigningCertificate(ctx context.Context, request *fulciogrpc.CreateSigningCertificateRequest) (*fulciogrpc.SigningCertificate, error) {
 	logger := log.ContextLogger(ctx)
 
 	// OIDC token either is passed in gRPC field or was extracted from HTTP headers
@@ -231,7 +236,7 @@ func (g *GRPCCAServer) CreateSigningCertificate(ctx context.Context, request *fu
 	return result, nil
 }
 
-func (g *GRPCCAServer) GetTrustBundle(ctx context.Context, _ *fulciogrpc.GetTrustBundleRequest) (*fulciogrpc.TrustBundle, error) {
+func (g *grpcaCAServer) GetTrustBundle(ctx context.Context, _ *fulciogrpc.GetTrustBundleRequest) (*fulciogrpc.TrustBundle, error) {
 	trustBundle, err := g.ca.TrustBundle(ctx)
 	if err != nil {
 		return nil, handleFulcioGRPCError(ctx, codes.Internal, err, retrieveTrustBundleCAError)
@@ -255,7 +260,7 @@ func (g *GRPCCAServer) GetTrustBundle(ctx context.Context, _ *fulciogrpc.GetTrus
 	return resp, nil
 }
 
-func (g *GRPCCAServer) GetConfiguration(ctx context.Context, _ *fulciogrpc.GetConfigurationRequest) (*fulciogrpc.Configuration, error) {
+func (g *grpcaCAServer) GetConfiguration(ctx context.Context, _ *fulciogrpc.GetConfigurationRequest) (*fulciogrpc.Configuration, error) {
 	cfg := config.FromContext(ctx)
 	if cfg == nil {
 		err := errors.New("configuration not loaded")
@@ -267,10 +272,10 @@ func (g *GRPCCAServer) GetConfiguration(ctx context.Context, _ *fulciogrpc.GetCo
 	}, nil
 }
 
-func (g *GRPCCAServer) Check(_ context.Context, _ *health.HealthCheckRequest) (*health.HealthCheckResponse, error) {
+func (g *grpcaCAServer) Check(_ context.Context, _ *health.HealthCheckRequest) (*health.HealthCheckResponse, error) {
 	return &health.HealthCheckResponse{Status: health.HealthCheckResponse_SERVING}, nil
 }
 
-func (g *GRPCCAServer) Watch(_ *health.HealthCheckRequest, _ health.Health_WatchServer) error {
+func (g *grpcaCAServer) Watch(_ *health.HealthCheckRequest, _ health.Health_WatchServer) error {
 	return status.Error(codes.Unimplemented, "unimplemented")
 }