protocol: connection helper

Signed-off-by: Maciek Borzecki <maciek.borzecki@gmail.com>

protocol/connection.go

@@ -0,0 +1,59 @@
+//    Licensed under the Apache License, Version 2.0 (the "License");
+//    you may not use this file except in compliance with the License.
+//    You may obtain a copy of the License at
+//
+//        http://www.apache.org/licenses/LICENSE-2.0
+//
+//    Unless required by applicable law or agreed to in writing, software
+//    distributed under the License is distributed on an "AS IS" BASIS,
+//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//    See the License for the specific language governing permissions and
+//    limitations under the License.
+package protocol
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+
+	"github.com/pkg/errors"
+
+	"github.com/bboozzoo/mconnect/logger"
+	"github.com/bboozzoo/mconnect/protocol/packet"
+)
+
+type Connection struct {
+	conn net.Conn
+}
+
+type Configuration struct {
+	Cert     *tls.Certificate
+	Identity *packet.Identity
+}
+
+func Dial(ctx context.Context, where string, conf *Configuration) (*Connection, error) {
+	log := logger.FromContext(ctx)
+
+	dialer := net.Dialer{}
+	conn, err := dialer.DialContext(ctx, "tcp", where)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to dial %s", where)
+	}
+	log.Debugf("connected to %v", conn.RemoteAddr())
+
+	e := packet.NewEncoder(conn)
+	if err := e.Encode(packet.NewIdentity(conf.Identity)); err != nil {
+		return nil, errors.Wrapf(err, "failed to send identity")
+	}
+
+	log.Debugf("identity sent")
+
+	return &Connection{conn: conn}, nil
+}
+
+func (c *Connection) Close() error {
+	if c.conn != nil {
+		c.conn.Close()
+	}
+	return nil
+}