/
ping.go
119 lines (99 loc) · 2.41 KB
/
ping.go
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package mtproto
import (
"context"
"github.com/go-faster/errors"
"github.com/gotd/td/bin"
"github.com/gotd/td/crypto"
"github.com/gotd/td/mt"
)
// Ping sends ping request to server and waits until pong is received or
// context is canceled.
func (c *Conn) Ping(ctx context.Context) error {
// Generating random id.
// Probably we should check for collisions here.
pingID, err := crypto.RandInt64(c.rand)
if err != nil {
return err
}
pong := c.pong(pingID)
defer c.removePong(pingID)
if err := c.writeServiceMessage(ctx, &mt.PingRequest{PingID: pingID}); err != nil {
return errors.Wrap(err, "write")
}
select {
case <-pong:
return nil
case <-ctx.Done():
return ctx.Err()
}
}
func (c *Conn) handlePong(b *bin.Buffer) error {
var pong mt.Pong
if err := pong.Decode(b); err != nil {
return errors.Errorf("decode: %x", err)
}
c.log.Debug("Pong")
c.pingMux.Lock()
ch, ok := c.ping[pong.PingID]
if ok {
close(ch)
delete(c.ping, pong.PingID)
}
c.pingMux.Unlock()
return nil
}
func (c *Conn) pingDelayDisconnect(ctx context.Context, delay int) error {
// Generating random id.
// Probably we should check for collisions here.
pingID, err := crypto.RandInt64(c.rand)
if err != nil {
return err
}
pong := c.pong(pingID)
defer c.removePong(pingID)
if err := c.writeServiceMessage(ctx, &mt.PingDelayDisconnectRequest{
PingID: pingID,
DisconnectDelay: delay,
}); err != nil {
return errors.Wrap(err, "write")
}
select {
case <-pong:
return nil
case <-ctx.Done():
return ctx.Err()
}
}
func (c *Conn) pong(pingID int64) chan struct{} {
ch := make(chan struct{})
c.pingMux.Lock()
c.ping[pingID] = ch
c.pingMux.Unlock()
return ch
}
func (c *Conn) removePong(pingID int64) {
c.pingMux.Lock()
delete(c.ping, pingID)
c.pingMux.Unlock()
}
func (c *Conn) pingLoop(ctx context.Context) error {
// If the client sends these pings once every 60 seconds,
// for example, it may set disconnect_delay equal to 75 seconds.
delay := c.pingInterval + c.pingTimeout
ticker := c.clock.Ticker(c.pingInterval)
defer ticker.Stop()
for {
select {
case <-ctx.Done():
return errors.Wrap(ctx.Err(), "ping loop")
case <-ticker.C():
if err := func() error {
ctx, cancel := context.WithTimeout(ctx, c.pingTimeout)
defer cancel()
return c.pingDelayDisconnect(ctx, int(delay.Seconds()))
}(); err != nil {
return errors.Wrap(err, "disconnect (pong missed)")
}
}
}
}