grpcdb: Better readability for docs and constructor names

* Added some docs for NewClient, BindServer, *server.Init
* Security level clarified, whether "secure" for https
or "insecure" for non-https gRPC connections.

grpcdb/client.go

@@ -6,9 +6,19 @@ import (
 	protodb "github.com/tendermint/tmlibs/proto"
 )
 
-func NewClient(serverAddr string, secure bool) (protodb.DBClient, error) {
+// Security defines how the client will talk to the gRPC server.
+type Security uint
+
+const (
+	Insecure Security = iota
+	Secure
+)
+
+// NewClient creates a gRPC client connected to the bound gRPC server at serverAddr.
+// Use kind to set the level of security to either Secure or Insecure.
+func NewClient(serverAddr string, kind Security) (protodb.DBClient, error) {
 	var opts []grpc.DialOption
-	if !secure {
+	if kind == Insecure {
 		opts = append(opts, grpc.WithInsecure())
 	}
 	cc, err := grpc.Dial(serverAddr, opts...)

grpcdb/example_test.go

@@ -12,12 +12,12 @@ import (
 func Example() {
 	addr := ":8998"
 	go func() {
-		if err := grpcdb.BindRemoteDBServer(addr); err != nil {
+		if err := grpcdb.BindServer(addr); err != nil {
-			log.Fatalf("BindRemoteDBServer: %v", err)
+			log.Fatalf("BindServer: %v", err)
 		}
 	}()
 
-	client, err := grpcdb.NewClient(addr, false)
+	client, err := grpcdb.NewClient(addr, grpcdb.Insecure)
 	if err != nil {
 		log.Fatalf("Failed to create grpcDB client: %v", err)
 	}

grpcdb/server.go

@@ -1,8 +1,8 @@
 package grpcdb
 
 import (
-"log"
 	"context"
+	"log"
 	"net"
 	"sync"
 	"time"
@@ -13,7 +13,10 @@ import (
 	protodb "github.com/tendermint/tmlibs/proto"
 )
 
-func BindRemoteDBServer(addr string, opts ...grpc.ServerOption) error {
+// BindServer is a blocking function that sets up a gRPC based
+// server at the address supplied, with the gRPC options passed in.
+// Normally in usage, invoke it in a goroutine like you would for http.ListenAndServe.
+func BindServer(addr string, opts ...grpc.ServerOption) error {
 	ln, err := net.Listen("tcp", addr)
 	if err != nil {
 		return err
@@ -30,11 +33,24 @@ type server struct {
 
 var _ protodb.DBServer = (*server)(nil)
 
+// Init initializes the server's database. Only one type of database
+// can be initialized per server.
+//
+// Dir is the directory on the file system in which the DB will be stored(if backed by disk) (TODO: remove)
+//
+// Name is representative filesystem entry's basepath
+//
+// Type can be either one of:
+//  * cleveldb (if built with gcc enabled)
+//  * fsdb
+//  * memdB
+//  * leveldb
+// See https://godoc.org/github.com/tendermint/tmlibs/db#DBBackendType
 func (s *server) Init(ctx context.Context, in *protodb.Init) (*protodb.Entity, error) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
-log.Printf("in: %+v\n", in)
+	log.Printf("in: %+v\n", in)
 	s.db = db.NewDB(in.Name, db.DBBackendType(in.Type), in.Dir)
 	return &protodb.Entity{TimeAt: time.Now().Unix()}, nil
 }
@@ -45,6 +61,7 @@ func (s *server) Delete(ctx context.Context, in *protodb.Entity) (*protodb.Nothi
 }
 
 var nothing = new(protodb.Nothing)
+
 func (s *server) DeleteSync(ctx context.Context, in *protodb.Entity) (*protodb.Nothing, error) {
 	s.db.DeleteSync(in.Key)
 	return nothing, nil