First iteration of selfpass gRPC backend, w/ credentials CRUD functional

cmd/server/server.go

@@ -0,0 +1,90 @@
+package main
+
+import (
+	"flag"
+	"io"
+	"net"
+	"os"
+	"os/signal"
+
+	"github.com/go-kit/kit/log"
+	"github.com/mitchell/selfpass/credentials/protobuf"
+	"github.com/mitchell/selfpass/credentials/repositories"
+	"github.com/mitchell/selfpass/credentials/service"
+	"github.com/mitchell/selfpass/credentials/transport"
+	"google.golang.org/grpc"
+)
+
+var logger log.Logger
+
+func main() {
+	var (
+		stop      = make(chan os.Signal)
+		dev       = flag.Bool("dev", false, "enables dev mode logging")
+		port      = flag.String("port", "8080", "specify the port to listen on")
+		tableName = flag.String(
+			"credential-table-name",
+			"selfpass-credential",
+			"specify the credential table name on AWS",
+		)
+	)
+
+	signal.Notify(stop, os.Interrupt)
+	flag.Parse()
+
+	logger = newLogger(os.Stdout, *dev)
+
+	var (
+		db   = repositories.NewDynamoTable(*tableName)
+		svc  = service.NewCredentials(db)
+		gsrv = transport.NewGRPCServer(svc, logger)
+		srv  = grpc.NewServer()
+	)
+	protobuf.RegisterCredentialServiceServer(srv, gsrv)
+
+	addr := "0.0.0.0:" + *port
+	lis, err := net.Listen("tcp", addr)
+	check(err)
+
+	go func() {
+		logger.Log(
+			"message", "serving",
+			"address", addr,
+			"credentialTable", tableName,
+			"dev", dev,
+		)
+		check(srv.Serve(lis))
+	}()
+
+	<-stop
+	logger.Log("message", "gracefully stopping")
+	srv.GracefulStop()
+}
+
+func newLogger(writer io.Writer, dev bool) log.Logger {
+	var l log.Logger
+	writer = log.NewSyncWriter(writer)
+
+	if dev {
+		l = log.NewLogfmtLogger(writer)
+	} else {
+		l = log.NewJSONLogger(writer)
+	}
+	l = log.WithPrefix(l, "caller", log.DefaultCaller, "timestamp", log.DefaultTimestamp)
+
+	lfunc := log.LoggerFunc(func(in ...interface{}) error {
+		if err := l.Log(in...); err != nil {
+			panic(err.Error())
+		}
+		return nil
+	})
+
+	return lfunc
+}
+
+func check(err error) {
+	if err != nil {
+		logger.Log("error", err)
+		os.Exit(1)
+	}
+}