// LookupUserHashes makes query on the grid to get availabilty information for given UserHash values.
func (t *telegraph) lookupUserHashes(userHashes []string) (*LookupResponse, error) {
defer t.waitGroup.Done()
var p ProtocolMessage
var l protocol.LookupUserHashesMsg
var wg sync.WaitGroup
var lr lookupResponse
// Send LookupUserHashesMsg to all the connected Newton nodes and wait for response.
hosts := t.pool.GetActiveConnections()
if len(hosts) == 0 {
return nil, ErrNoActiveConnection
}
for _, h := range hosts {
mID, c, err := t.messageStore.NewMessage()
if err != nil {
return nil, err
}
l = protocol.LookupUserHashesMsg{
Action: protocol.LookupUserHashes,
Version: protocol.Version,
UserHashes: userHashes,
MessageID: mID,
}
m, err := pool.MsgToByte(l)
if err != nil {
return nil, err
}
p = ProtocolMessage{
Data: m,
Connection: h,
}
t.protocolOutput <- p
// Listen for the response
wg.Add(1)
go lr.waitForResponse(&wg, h, c)
}
// Wait for all gorutines to complete. It will takes 1 second at max.
wg.Wait()
// Prepare a response message and return it
r := &LookupResponse{
UserClientItems: lr.UserClientItems,
Pending: lr.Pending,
Timeouts: lr.Timeouts,
}
return r, nil
}
func (d *dispatcher) prepareMessage(userHash string, clientID uint32, messageType int, data []byte) ([]byte, error) {
sm := protocol.SendMessageMsg{
Action: protocol.SendMessage,
Version: protocol.Version,
UserHash: userHash,
MessageType: websocket.BinaryMessage,
ClientID: clientID,
Body: hex.EncodeToString(data),
}
m, err := pool.MsgToByte(sm)
if err != nil {
return nil, err
}
return m, nil
}