// Dial is used to create a new outgoing connection
func (l *RaftLayer) Dial(address string, timeout time.Duration) (net.Conn, error) {
conn, err := net.DialTimeout("tcp", address, timeout)
if err != nil {
return nil, err
}
// Check for tls mode
if l.tlsConfig != nil {
// Switch the connection into TLS mode
if _, err := conn.Write([]byte{byte(rpcTLS)}); err != nil {
conn.Close()
return nil, err
}
// Wrap the connection in a TLS client
conn, err = tlsutil.WrapTLSClient(conn, l.tlsConfig)
if err != nil {
return nil, err
}
}
// Write the Raft byte to set the mode
_, err = conn.Write([]byte{byte(rpcRaft)})
if err != nil {
conn.Close()
return nil, err
}
return conn, err
}
// getNewConn is used to return a new connection
func (p *ConnPool) getNewConn(addr net.Addr, version int) (*Conn, error) {
// Try to dial the conn
conn, err := net.DialTimeout("tcp", addr.String(), 10*time.Second)
if err != nil {
return nil, err
}
// Cast to TCPConn
if tcp, ok := conn.(*net.TCPConn); ok {
tcp.SetKeepAlive(true)
tcp.SetNoDelay(true)
}
// Check if TLS is enabled
if p.tlsConfig != nil {
// Switch the connection into TLS mode
if _, err := conn.Write([]byte{byte(rpcTLS)}); err != nil {
conn.Close()
return nil, err
}
// Wrap the connection in a TLS client
tlsConn, err := tlsutil.WrapTLSClient(conn, p.tlsConfig)
if err != nil {
conn.Close()
return nil, err
}
conn = tlsConn
}
// Switch the multiplexing based on version
var session muxSession
if version < 2 {
// Write the Consul multiplex byte to set the mode
if _, err := conn.Write([]byte{byte(rpcMultiplex)}); err != nil {
conn.Close()
return nil, err
}
// Create a multiplexed session
session = &muxadoWrapper{muxado.Client(conn)}
} else {
// Write the Consul multiplex byte to set the mode
if _, err := conn.Write([]byte{byte(rpcMultiplexV2)}); err != nil {
conn.Close()
return nil, err
}
// Setup the logger
conf := yamux.DefaultConfig()
conf.LogOutput = p.logOutput
// Create a multiplexed session
session, _ = yamux.Client(conn, conf)
}
// Wrap the connection
var c *Conn
// Track this connection, handle potential race condition
p.Lock()
defer p.Unlock()
if existing := p.pool[addr.String()]; existing != nil {
c = existing
} else {
c = &Conn{
refCount: 1,
addr: addr,
session: session,
clients: list.New(),
lastUsed: time.Now(),
version: version,
pool: p,
}
p.pool[addr.String()] = c
}
return c, nil
}