func()

in internal/proxy/proxy.go [735:780]

• 35 lines of code
• 9 McCabe index (conditional complexity)

func (c *Client) serveSocketMount(_ context.Context, s *socketMount) error {
	for {
		cConn, err := s.Accept()
		if err != nil {
			if nerr, ok := err.(net.Error); ok && nerr.Timeout() {
				c.logger.Errorf("[%s] Error accepting connection: %v", s.inst, err)
				// For transient errors, wait a small amount of time to see if it resolves itself
				time.Sleep(10 * time.Millisecond)
				continue
			}
			return err
		}
		// handle the connection in a separate goroutine
		go func() {
			c.logger.Infof("[%s] Accepted connection from %s", s.inst, cConn.RemoteAddr())

			// A client has established a connection to the local socket. Before
			// we initiate a connection to the Cloud SQL backend, increment the
			// connection counter. If the total number of connections exceeds
			// the maximum, refuse to connect and close the client connection.
			count := atomic.AddUint64(&c.connCount, 1)
			defer atomic.AddUint64(&c.connCount, ^uint64(0))

			if c.conf.MaxConnections > 0 && count > c.conf.MaxConnections {
				c.logger.Infof("max connections (%v) exceeded, refusing new connection", c.conf.MaxConnections)
				if c.connRefuseNotify != nil {
					go c.connRefuseNotify()
				}
				_ = cConn.Close()
				return
			}

			// give a max of 30 seconds to connect to the instance
			ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
			defer cancel()

			sConn, err := c.dialer.Dial(ctx, s.inst, s.dialOpts...)
			if err != nil {
				c.logger.Errorf("[%s] failed to connect to instance: %v", s.inst, err)
				_ = cConn.Close()
				return
			}
			c.proxyConn(s.inst, cConn, sConn)
		}()
	}
}