// SendGroup triggers a group of parallel tasks
func (server *Server) SendGroup(group *Group) ([]*backends.AsyncResult, error) {
// Make sure result backend is defined
if server.backend == nil {
return nil, errors.New("Result backend required")
}
asyncResults := make([]*backends.AsyncResult, len(group.Tasks))
var wg sync.WaitGroup
wg.Add(len(group.Tasks))
errorsChan := make(chan error)
// Init group
server.backend.InitGroup(group.GroupUUID, group.GetUUIDs())
for i, signature := range group.Tasks {
go func(s *signatures.TaskSignature, index int) {
defer wg.Done()
// Set initial task states to PENDING
if err := server.backend.SetStatePending(s); err != nil {
errorsChan <- err
return
}
// Publish task
if err := server.broker.Publish(s); err != nil {
errorsChan <- fmt.Errorf("Publish Message: %v", err)
return
}
asyncResults[index] = backends.NewAsyncResult(s, server.backend)
}(signature, i)
}
done := make(chan int)
go func() {
wg.Wait()
done <- 1
}()
select {
case err := <-errorsChan:
return asyncResults, err
case <-done:
return asyncResults, nil
}
}
// SendTask publishes a task to the default queue
func (server *Server) SendTask(signature *signatures.TaskSignature) (*backends.AsyncResult, error) {
// Make sure result backend is defined
if server.backend == nil {
return nil, errors.New("Result backend required")
}
// Auto generate a UUID if not set already
if signature.UUID == "" {
signature.UUID = fmt.Sprintf("task_%v", uuid.New())
}
// Set initial task state to PENDING
if err := server.backend.SetStatePending(signature); err != nil {
return nil, fmt.Errorf("Set State Pending: %v", err)
}
if err := server.broker.Publish(signature); err != nil {
return nil, fmt.Errorf("Publish Message: %v", err)
}
return backends.NewAsyncResult(signature, server.backend), nil
}