func (vs *viewState) startConn() {
certpool := x509.NewCertPool()
if !certpool.AppendCertsFromPEM(comm.CA()) { // Add CA public cert.
panic("failed to add cert")
}
creds := credentials.NewTLS(&tls.Config{
RootCAs: certpool,
})
errClosed := errors.New("closed")
backer := backoff.New(time.Millisecond*500, time.Millisecond*10)
do := func() error {
conn, err := grpc.Dial(fmt.Sprintf("%s:%d", comm.Host(), comm.Port()),
grpc.WithTimeout(time.Second*3),
grpc.FailOnNonTempDialError(true),
grpc.WithTransportCredentials(creds),
)
if err != nil {
return err
}
defer conn.Close()
client := comm.NewGarageClient(conn)
ctx := context.TODO()
noop := &comm.Noop{}
_, err = client.Ping(ctx, noop)
if err != nil {
return err
}
vs.mu.Lock()
vs.connErr = nil
vs.pingOk = true
vs.mu.Unlock()
ticker := time.NewTicker(time.Millisecond * 1500)
defer ticker.Stop()
for {
select {
case <-vs.onClose:
return errClosed
case tm := <-vs.toggle:
if tm.Add(time.Second * 4).Before(time.Now()) {
continue
}
_, err = client.Toggle(ctx, noop)
if err != nil {
return err
}
case <-ticker.C:
_, err = client.Ping(ctx, noop)
if err != nil {
return err
}
vs.mu.Lock()
vs.pingOk = true
vs.mu.Unlock()
}
}
}
for {
err := do()
if err == errClosed {
return
}
if err != nil {
vs.mu.Lock()
vs.connErr = err
vs.pingOk = false
vs.mu.Unlock()
time.Sleep(backer.Duration())
continue
}
backer.Reset()
continue
}
}
"github.com/TheThingsNetwork/ttn/utils/backoff"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials"
)
// KeepAlive indicates the keep-alive time for the Dialer
var KeepAlive = 10 * time.Second
// MaxRetries indicates how often clients should retry dialing a component
var MaxRetries = 100
// DialOptions to use in TTN gRPC
var DialOptions = []grpc.DialOption{
WithTTNDialer(),
grpc.WithBlock(),
grpc.FailOnNonTempDialError(true),
}
func dial(address string, tlsConfig *tls.Config, fallback bool) (conn *grpc.ClientConn, err error) {
ctx := log.Get().WithField("Address", address)
opts := DialOptions
if tlsConfig != nil {
tlsConfig.ServerName = strings.SplitN(address, ":", 2)[0] // trim the port
opts = append(opts, grpc.WithTransportCredentials(credentials.NewTLS(tlsConfig)))
} else {
opts = append(opts, grpc.WithInsecure())
}
conn, err = grpc.Dial(
address,
opts...,
)
