mirror of
https://github.com/netbirdio/netbird.git
synced 2024-12-15 19:31:06 +01:00
97 lines
2.1 KiB
Go
97 lines
2.1 KiB
Go
package dialer
|
|
|
|
import (
|
|
"context"
|
|
"errors"
|
|
"net"
|
|
"time"
|
|
|
|
log "github.com/sirupsen/logrus"
|
|
)
|
|
|
|
var (
|
|
connectionTimeout = 30 * time.Second
|
|
)
|
|
|
|
type DialerFn interface {
|
|
Dial(ctx context.Context, address string) (net.Conn, error)
|
|
Protocol() string
|
|
}
|
|
|
|
type dialResult struct {
|
|
Conn net.Conn
|
|
Protocol string
|
|
Err error
|
|
}
|
|
|
|
type RaceDial struct {
|
|
log *log.Entry
|
|
serverURL string
|
|
dialerFns []DialerFn
|
|
}
|
|
|
|
func NewRaceDial(log *log.Entry, serverURL string, dialerFns ...DialerFn) *RaceDial {
|
|
return &RaceDial{
|
|
log: log,
|
|
serverURL: serverURL,
|
|
dialerFns: dialerFns,
|
|
}
|
|
}
|
|
|
|
func (r *RaceDial) Dial() (net.Conn, error) {
|
|
connChan := make(chan dialResult, len(r.dialerFns))
|
|
winnerConn := make(chan net.Conn, 1)
|
|
abortCtx, abort := context.WithCancel(context.Background())
|
|
defer abort()
|
|
|
|
for _, dfn := range r.dialerFns {
|
|
go r.dial(dfn, abortCtx, connChan)
|
|
}
|
|
|
|
go r.processResults(connChan, winnerConn, abort)
|
|
|
|
conn, ok := <-winnerConn
|
|
if !ok {
|
|
return nil, errors.New("failed to dial to Relay server on any protocol")
|
|
}
|
|
return conn, nil
|
|
}
|
|
|
|
func (r *RaceDial) dial(dfn DialerFn, abortCtx context.Context, connChan chan dialResult) {
|
|
ctx, cancel := context.WithTimeout(abortCtx, connectionTimeout)
|
|
defer cancel()
|
|
|
|
r.log.Infof("dialing Relay server via %s", dfn.Protocol())
|
|
conn, err := dfn.Dial(ctx, r.serverURL)
|
|
connChan <- dialResult{Conn: conn, Protocol: dfn.Protocol(), Err: err}
|
|
}
|
|
|
|
func (r *RaceDial) processResults(connChan chan dialResult, winnerConn chan net.Conn, abort context.CancelFunc) {
|
|
var hasWinner bool
|
|
for i := 0; i < len(r.dialerFns); i++ {
|
|
dr := <-connChan
|
|
if dr.Err != nil {
|
|
if errors.Is(dr.Err, context.Canceled) {
|
|
r.log.Infof("connection attempt aborted via: %s", dr.Protocol)
|
|
} else {
|
|
r.log.Errorf("failed to dial via %s: %s", dr.Protocol, dr.Err)
|
|
}
|
|
continue
|
|
}
|
|
|
|
if hasWinner {
|
|
if cerr := dr.Conn.Close(); cerr != nil {
|
|
r.log.Warnf("failed to close connection via %s: %s", dr.Protocol, cerr)
|
|
}
|
|
continue
|
|
}
|
|
|
|
r.log.Infof("successfully dialed via: %s", dr.Protocol)
|
|
|
|
abort()
|
|
hasWinner = true
|
|
winnerConn <- dr.Conn
|
|
}
|
|
close(winnerConn)
|
|
}
|