First version

internal/conn/conn.go

@@ -0,0 +1,50 @@
+package conn
+
+import (
+	"context"
+	"io"
+	"net"
+	"time"
+)
+
+type Conn struct {
+	netConn net.Conn
+}
+
+// FromNetConn wraps an existing net.Conn. Useful for tests.
+func FromNetConn(n net.Conn) *Conn { return &Conn{netConn: n} }
+
+func Dial(ctx context.Context, addr string, timeout time.Duration) (*Conn, error) {
+	d := net.Dialer{Timeout: timeout}
+	c, err := d.DialContext(ctx, "tcp", addr)
+	if err != nil {
+		return nil, err
+	}
+	return &Conn{netConn: c}, nil
+}
+
+func (c *Conn) Close() error {
+	if c.netConn == nil {
+		return nil
+	}
+	return c.netConn.Close()
+}
+
+func (c *Conn) Send(ctx context.Context, data []byte, timeout time.Duration) error {
+	if dl, ok := ctx.Deadline(); ok {
+		c.netConn.SetWriteDeadline(dl)
+	} else {
+		c.netConn.SetWriteDeadline(time.Now().Add(timeout))
+	}
+	_, err := c.netConn.Write(data)
+	return err
+}
+
+func (c *Conn) Receive(ctx context.Context, timeout time.Duration) ([]byte, error) {
+	if dl, ok := ctx.Deadline(); ok {
+		c.netConn.SetReadDeadline(dl)
+	} else {
+		c.netConn.SetReadDeadline(time.Now().Add(timeout))
+	}
+	return io.ReadAll(c.netConn)
+}