Hello Apache Beam community.
I'm asking because while creating a beam pipeline in Python, ReadFromKafka is
not working.
My code looks like this
```
@beam.ptransform_fn
def LogElements(input):
def log_element(elem):
print(elem)
return elem
return (
input | 'DoLog' >> Map(log_element)
)
if __name__ == '__main__':
consumer_config = {
'bootstrap.servers': '<bootstrap_server>'
}
with beam.Pipeline(options=PipelineOptions(['--streaming'])) as p:
(
p | ReadFromKafka(consumer_config=consumer_config,
topics=['input_topic'])
| "ToLines" >> beam.Map(lambda x: "%s %s" %
(x[0].decode("utf-8"), x[1].decode("utf-8")))
| 'Logging' >> LogElements()
)
```
This is a simple pipeline that simply subscribes to a topic in Kafka and
outputs to the console.
I've seen in the documentation that using ReadFromKafka in Python creates an
external java processor.
We also confirmed that it creates a process in VisualVM just fine.
However, I'm not sure why I'm not getting messages from Kafka.
* I checked the `_really_start_process` method of the `SubprocessServer` class
in subprocess_server.py to get the logs from the external java process.
