go-emlid/reach/client/socketio/client.go

package socketio

import (
	"sync"

	gosocketio "forge.cadoles.com/Pyxis/golang-socketio"
	"forge.cadoles.com/Pyxis/golang-socketio/transport"
	"github.com/pkg/errors"
)

type Channel = gosocketio.Channel

const (
	OnDisconnection = gosocketio.OnDisconnection
	OnConnection    = gosocketio.OnConnection
	OnError         = gosocketio.OnError
)

type Client struct {
	conn     *gosocketio.Client
	mutex    sync.RWMutex
	endpoint string
	opts     *Options
}

func (c *Client) Connect() error {
	c.mutex.Lock()
	defer c.mutex.Unlock()

	var err error
	var wg sync.WaitGroup

	wg.Add(1)

	transport := &transport.WebsocketTransport{
		PingInterval:   c.opts.PingInterval,
		PingTimeout:    c.opts.PingTimeout,
		ReceiveTimeout: c.opts.ReceiveTimeout,
		SendTimeout:    c.opts.SendTimeout,
		BufferSize:     c.opts.BufferSize,
	}

	conn, err := gosocketio.Dial(c.endpoint, transport)
	if err != nil {
		return errors.Wrap(err, "error while connecting to endpoint")
	}

	c.conn = nil

	cleanup := func() {
		conn.Off(gosocketio.OnError)
		conn.Off(gosocketio.OnConnection)
	}

	err = conn.On(gosocketio.OnConnection, func(h *Channel) {
		cleanup()
		wg.Done()
	})
	if err != nil {
		return errors.Wrap(err, "error while attaching to connection event")
	}

	err = conn.On(gosocketio.OnError, func(h *Channel) {
		cleanup()
		err = errors.Errorf("an unknown error occured")
		wg.Done()
	})
	if err != nil {
		return errors.Wrap(err, "error while attaching to error event")
	}

	wg.Wait()

	c.conn = conn

	return err
}

func (c *Client) Close() {
	c.mutex.Lock()
	defer c.mutex.Unlock()

	if c.conn == nil {
		return
	}
	c.conn.Close()
	c.conn = nil
}

func (c *Client) Alive() bool {
	c.mutex.RLock()
	defer c.mutex.RUnlock()

	if c.conn == nil {
		return false
	}

	return c.conn.IsAlive()
}

// Emit a new event with the given data
func (c *Client) Emit(event string, data any) error {
	c.mutex.RLock()
	defer c.mutex.RUnlock()

	if err := c.conn.Emit(event, data); err != nil {
		return errors.Wrapf(err, "error while emitting '%s' event", event)
	}
	return nil
}

type Handler func(ch *Channel, data any)

// On binds and event handler to the given event
func (c *Client) On(event string, handler Handler) error {
	c.mutex.RLock()
	defer c.mutex.RUnlock()

	return c.conn.On(event, handler)
}

// Off remove the handler bound to the given event
func (c *Client) Off(event string) {
	c.mutex.RLock()
	defer c.mutex.RUnlock()

	c.conn.Off(event)
}

func NewClient(endpoint string, funcs ...OptionFunc) *Client {
	opts := NewOptions(funcs...)
	client := &Client{
		endpoint: endpoint,
		opts:     opts,
	}
	return client
}