service: replace cmd with NewFlagSet, add internal service version metadata interceptors

client: add NewFlagSet, add missing Options interface methods

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

client/flags.go

@@ -0,0 +1,43 @@
+package client
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/caitlinelfring/go-env-default"
+	"github.com/spf13/pflag"
+)
+
+var u = strings.ToUpper
+
+func NewFlagSet() (*pflag.FlagSet, Option) {
+	const (
+		addr   = "address"
+		secure = "secure"
+		// caCert     = "ca-cert"
+		// clientCert = "client-cert"
+		// clientKey  = "client-key"
+	)
+	var (
+		optAddress string
+		optSecure  bool
+		// optCACert  string
+		// optCert    string
+		// optKey     string
+	)
+	flags := pflag.NewFlagSet("gRPC", pflag.ContinueOnError)
+	flags.StringVar(&optAddress, addr, env.GetDefault(u(addr), "0.0.0.0:0"), "Bind address for the server. 127.0.0.1:9090"+flagEnv(addr))
+	flags.BoolVar(&optSecure, secure, env.GetBoolDefault(u(secure), true), "Generate self signed certificate if none provided"+flagEnv(secure))
+	// flags.StringVar(&optCACert, caCert, "", "Path to Root CA certificate"+flagEnv(optCACert))
+	// flags.StringVar(&optCert, clientCert, "", "Path to Server certificate"+flagEnv(clientCert))
+	// flags.StringVar(&optKey, clientKey, "", "Path to Server key"+flagEnv(clientKey))
+	return flags, func(o *options) {
+		o.addr = optAddress
+		o.secure = optSecure
+
+	}
+}
+
+func flagEnv(name string) string {
+	return fmt.Sprintf(" [$%s]", strings.Replace(u(name), "-", "_", -1))
+}