streamsx.eventstreams 2.0.1

IBM Streams Event Streams integration for IBM Streams topology applications

Overview

Provides functions to read messages from IBM Event Streams as a stream and publish tuples to Event Streams as messages.

IBM® Event Streams is a fully managed, cloud-based messaging service. Built on Apache Kafka, IBM Event Streams is a high-throughput, fault-tolerant, event management platform that helps you build intelligent, responsive, event-driven applications.

You may also review the streamsx.kafka package. to integrate IBM Event Streams cloud service with your IBM Streams topology applications.

Sample

A simple hello world example of a Streams application publishing to a topic and the same application consuming the same topic:

from streamsx.topology.topology import Topology
from streamsx.topology.schema import CommonSchema
from streamsx.topology.context import submit, ContextTypes
import streamsx.eventstreams as eventstreams
import time

def delay(v):
    time.sleep(5.0)
    return True

topology = Topology('EventStreamsHelloWorld')

to_evstr = topology.source(['Hello', 'World!'])
to_evstr = to_evstr.as_string()
# delay tuple by tuple
to_evstr = to_evstr.filter(delay)

# Publish a stream to Event Streams using HELLO topic
eventstreams.publish(to_evstr, topic='HELLO')

# Subscribe to same topic as a stream
from_evstr = eventstreams.subscribe(topology, schema=CommonSchema.String, topic='HELLO')

# You'll find the Hello World! in stdout log file:
from_evstr.print()

# finally submit the topology to a Streaming  Analytics Service instance
submit(ContextTypes.STREAMING_ANALYTICS_SERVICE, topology)

Documentation

• streamsx.eventstreams package documentation