My talk at Google DevFest Switzerland, Fribourg, Oct 2017. https://devfest.ch/schedule/day1?sessionId=118 Abstract: Modern businesses have data at their core, and this data is changing continuously. How can we harness this torrent of information in real-time? The answer is stream processing, and the technology that has since become the core platform for streaming data is Apache Kafka. Among the thousands of companies that use Kafka to transform and reshape their industries are the likes of Netflix, Uber, PayPal, and AirBnB, but also established players such as Goldman Sachs, Cisco, and Oracle. Unfortunately, today’s common architectures for real-time data processing at scale suffer from complexity: there are many technologies that need to be stitched and operated together, and each individual technology is often complex by itself. This has led to a strong discrepancy between how we, as engineers, would like to work vs. how we actually end up working in practice. In this session we talk about how Apache Kafka helps you to radically simplify your data architectures. We cover how you can now build normal applications to serve your real-time processing needs — rather than building clusters or similar special-purpose infrastructure — and still benefit from properties such as high scalability, distributed computing, and fault-tolerance, which are typically associated exclusively with cluster technologies. We discuss common use cases to realize that stream processing in practice often requires database-like functionality, and how Kafka allows you to bridge the worlds of streams and databases when implementing your own core business applications (inventory management for large retailers, patient monitoring in healthcare, fleet tracking in logistics, etc), for example in the form of event-driven, containerized microservices. We will also give a brief shout-out to the recently launched KSQL, a streaming SQL engine for Apache Kafka.

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Rethinking Stream Processing
with Apache Kafka:
Applications vs. Clusters,
Streams vs. Databases
Michael G. Noll, Confluent
@miguno
Google GDG DevFest Switzerland, October 28-29, 2017

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0.11 Exactly-once
semantics
0.10 Data processing (Streams API)
0.9 Data integration (Connect API)
Intra-cluster
replication
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2012 2014 2015 2016 2017
Cluster mirroring0.7
2013
Apache Kafka: birthed as a messaging system, now a streaming platform

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,

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(Does NOT run inside
the Kafka brokers!)

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(Does NOT run inside
the Kafka brokers!)

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http://docs.confluent.io/current/streams/kafka-streams-examples/docs/index.html

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Before

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Before
With Kafka’s
Streams API

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KStream<Integer, Integer> input =
builder.stream("numbers-topic");
// Stateless computation
KStream<Integer, Integer> doubled =
input.mapValues(v -> v * 2);
// Stateful computation
KTable<Integer, Integer> sumOfOdds = input
.filter((k,v) -> v % 2 != 0)
.selectKey((k, v) -> 1)
.groupByKey()
.reduce((v1, v2) -> v1 + v2, "sum-of-odds");
class PrintToConsoleProcessor
implements Processor<K, V> {
@Override
public void init(ProcessorContext context) {}
@Override
void process(K key, V value) {
System.out.println("Got value " + value);
}
@Override
void punctuate(long timestamp) {}
@Override
void close() {}
}

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Linux Windows

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http://www.confluent.io/blog/introducing-kafka-streams-stream-processing-made-simple
https://kafka.apache.org/documentation/streams#streams_duality

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…and many more…

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…and many more…

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Kafka 1.0*
2016 2017
First release of Kafka’s
Streams API (0.10.0)
today
Kafka Streams API in the wild In production at LINE Corp., Japan
220+ million active users, processing millions of msg/s
“Applying Kafka Streams for internal message delivery pipeline”
https://engineering.linecorp.com/en/blog/detail/80

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49. 49Supported since Apache Kafka 0.11 (June 2017)

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…and more…

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$ curl -sXGET http://localhost:7070/kafka-music/charts/top-five
[
{
"artist": "Subhumans",
"album": "Live In A Dive",
"name": "All Gone Dead",
"plays": 126
},
{
"artist": "Wheres The Pope?",
"album": "PSI",
"name": "Fear Of God",
"plays": 115
},
...
]

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https://kafka.apache.org/documentation/streams
http://docs.confluent.io/current/streams/
https://www.confluent.io/downloads/

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KSQL: a Streaming SQL Engine for Apache Kafka™ from Confluent
ü No coding required, all you need is SQL
ü No separate processing cluster required
ü Powered by Kafka: elastic, scalable,
distributed, battle-tested
CREATE TABLE possible_fraud AS
SELECT card_number, count(*)
FROM authorization_attempts
WINDOW TUMBLING (SIZE 5 SECONDS)
GROUP BY card_number
HAVING count(*) > 3;
CREATE STREAM vip_actions AS
SELECT userid, page, action
FROM clickstream c
LEFT JOIN users u
ON c.userid = u.userid
WHERE u.level = ‘Platinum’;
KSQL is the simplest way to process streams of data in real-time
ü Perfect for streaming ETL, anomaly detection,
event monitoring, and more
ü Part of Confluent Open Source
https://github.com/confluentinc/ksql