Initial QSfera import

Server/pkg/service/grpc/client.go

@@ -0,0 +1,103 @@
+package grpc
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"errors"
+	"os"
+
+	mgrpcc "github.com/go-micro/plugins/v4/client/grpc"
+	mtracer "github.com/go-micro/plugins/v4/wrapper/trace/opentelemetry"
+	"github.com/qsfera/server/pkg/registry"
+	"github.com/qsfera/server/pkg/shared"
+	"go-micro.dev/v4/client"
+	"go.opentelemetry.io/otel/trace"
+	"go.opentelemetry.io/otel/trace/noop"
+)
+
+// ClientOptions represent options (e.g. tls settings) for the grpc clients
+type ClientOptions struct {
+	tlsMode string
+	caCert  string
+	tp      trace.TracerProvider
+}
+
+// Option is used to pass client options
+type ClientOption func(opts *ClientOptions)
+
+// WithTLSMode allows setting the TLSMode option for grpc clients
+func WithTLSMode(v string) ClientOption {
+	return func(o *ClientOptions) {
+		o.tlsMode = v
+	}
+}
+
+// WithTLSCACert allows setting the CA Certificate for grpc clients
+func WithTLSCACert(v string) ClientOption {
+	return func(o *ClientOptions) {
+		o.caCert = v
+	}
+}
+
+// WithTraceProvider allows to set the trace Provider for grpc clients
+func WithTraceProvider(tp trace.TracerProvider) ClientOption {
+	return func(o *ClientOptions) {
+		if tp != nil {
+			o.tp = tp
+		} else {
+			o.tp = noop.NewTracerProvider()
+		}
+	}
+}
+
+func GetClientOptions(t *shared.GRPCClientTLS) []ClientOption {
+	opts := []ClientOption{
+		WithTLSMode(t.Mode),
+		WithTLSCACert(t.CACert),
+	}
+	return opts
+}
+
+func NewClient(opts ...ClientOption) (client.Client, error) {
+	var options ClientOptions
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	reg := registry.GetRegistry()
+	var tlsConfig *tls.Config
+	cOpts := []client.Option{
+		client.Registry(reg),
+		client.Wrap(mtracer.NewClientWrapper(
+			mtracer.WithTraceProvider(options.tp),
+		)),
+	}
+	switch options.tlsMode {
+	case "insecure":
+		tlsConfig = &tls.Config{
+			InsecureSkipVerify: true,
+		}
+		cOpts = append(cOpts, mgrpcc.AuthTLS(tlsConfig))
+	case "on":
+		tlsConfig = &tls.Config{
+			MinVersion: tls.VersionTLS12,
+		}
+		// Note: If caCert is empty we use the system's default set of trusted CAs
+		if options.caCert != "" {
+			certs := x509.NewCertPool()
+			pemData, err := os.ReadFile(options.caCert)
+			if err != nil {
+				return nil, err
+			}
+			if !certs.AppendCertsFromPEM(pemData) {
+				return nil, errors.New("could not initialize client, adding CA cert failed")
+			}
+			tlsConfig.RootCAs = certs
+		}
+		cOpts = append(cOpts, mgrpcc.AuthTLS(tlsConfig))
+		// case "off":
+		// default:
+	}
+
+	return mgrpcc.NewClient(cOpts...), nil
+}