Generating custom command not streaming output

[jakubzak]

I have created following custom command:

@Configuration(streaming=True)
class GenerateTextCommand(GeneratingCommand):

  count = Option(require=True, validate=validators.Integer(0))
  text = Option(require=True)

  def generate(self):
    for i in range(1, self.count + 1):
       sleep(5)
       yield {'id': i, '_time': time.time(), '_raw': unicode(i) + '. ' + self.text}

dispatch(GenerateTextCommand, sys.argv, sys.stdin, sys.stdout, __name__)

and I have prepared configuration in commands.conf:

[teststream]
filename = testStream.py
chunked = true

My expectation is that if I execute this command in Search command line in Splunk UI:

| teststream count=4 text="asdf"

It will print out each 5 seconds asdf text 4 times. Instead of it it generates 4 events and prints it after 20 seconds. Timestamps shows that generation time is strictly by "my rules" - new message each 5 seconds.

Is my understanding of "output streaming" from custom command incorrect or am I doing something wrong?

Thanks for help

Jakub