java


using kafka-streams to conditionally sort a json input stream


I am new to developing kafka-streams applications. My stream processor is meant to sort json messages based on a value of a user key in the input json message.
Message 1: {"UserID": "1", "Score":"123", "meta":"qwert"}
Message 2: {"UserID": "5", "Score":"780", "meta":"mnbvs"}
Message 3: {"UserID": "2", "Score":"0", "meta":"fghjk"}
I have read here Dynamically connecting a Kafka input stream to multiple output streams that there is no dynamic solution.
In my use-case I know the user keys and output topics that I need to sort the input stream. So I am writing separate processor applications specific to each user where each processor application matches a different UserID.
All the different stream processor applications read from the same json input topic in kafka but each one only writes the message to a output topic for a specific user if the preset user condition is met.
public class SwitchStream extends AbstractProcessor<String, String> {
#Override
public void process(String key, String value) {
HashMap<String, String> message = new HashMap<>();
ObjectMapper mapper = new ObjectMapper();
try {
message = mapper.readValue(value, HashMap.class);
} catch (IOException e){}
// User condition UserID = 1
if(message.get("UserID").equals("1")) {
context().forward(key, value);
context().commit();
}
}
public static void main(String[] args) throws Exception {
Properties props = new Properties();
props.put(StreamsConfig.APPLICATION_ID_CONFIG, "sort-stream-processor");
props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(StreamsConfig.KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
props.put(StreamsConfig.VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
TopologyBuilder builder = new TopologyBuilder();
builder.addSource("Source", "INPUT_TOPIC");
builder.addProcessor("Process", SwitchStream::new, "Source");
builder.addSink("Sink", "OUTPUT_TOPIC", "Process");
KafkaStreams streams = new KafkaStreams(builder, props);
streams.start();
}
}
Question 1:
Is it possible to achieve the same functionality easily using the High-Level Streams DSL instead if the Low-Level Processor API? (I admit I found it harder understand and follow the other online examples of the High-Level Streams DSL)
Question 2:
The input json topic is getting input at a high rate 20K-25K EPS. My processor applications don't seem to be able to keep pace with this input stream. I have tried deploying multiple instances of each process but the results are nowhere close to where I want them to be. Ideally each processor instance should be able to process 3-5K EPS.
Is there a way to improve my processor logic or write the same processor logic using the high level streams DSL? would that make a difference?
You can do this in high-level DSL via filter() (you effectively implemented a filter as you only return a message if it's userID==1). You could generalize this filter pattern, by using KStream#branch() (see the docs for further details: http://docs.confluent.io/current/streams/developer-guide.html#stateless-transformations). Also read the JavaDocs: http://kafka.apache.org/0102/javadoc/index.html?org/apache/kafka/streams
KStreamBuilder builder = new KStreamBuilder();
builder.stream("INPUT_TOPIC")
.filter(new Predicate() {
#Overwrite
boolean test(String key, String value) {
// put you processor logic here
return message.get("UserID").equals("1")
}
})
.to("OUTPUT_TOPIC");
About performance. A single instance should be able to process 10K+ records. It's hard to tell without any further information what the problem might be. I would recommend to ask at Kafka user list (see http://kafka.apache.org/contact)

Related Links

How to remove an unknown enum key on Jackson deserialization?
Using Swagger annotations to document request body of array type
Apache Storm: What does the OutputCollector.fail() method do?
Ignoring FileNotFoundExceptions in jsp's (Weblogic)
twitter4j group direct message
How to specify SSL/TLS version on Java LDAP connection?
Actions aren't showing on Toolbar with “ifRoom”
How Can I validate the credentials in my database using Spring security and Restful web services?
How to force compile error with aspectJ pointcut mismatch
Why do we use this code in JAVA? [duplicate]
Generic Header and Footer in spring batch for all file formats
How actually applicationServlet manages context varibles?
How to modify date format?
JHipster backend - Social login
How to track downloading of file with Web Automation and Selenium?
Cassandra UDT mapping issue

Categories

HOME
sendgrid
gitlab
debugging
mockito
dictionary
vmware
webpack-2
disassembler
fingerprint
ojdbc
azure-storage-tables
cross-validation
basic
medical
quickbooks
etl
vb.net-2010
usergrid
quickfix
ghc
google-cloud-speech
physics-engine
tibco-mdm
assistant
atlassian-crucible
quote
calibre
force-layout
revolution-slider
file-format
main
lto
dynamics-crm-2013
hilbert-curve
xenforo
az-application-insights
ansible-playbook
splice
quadratic-programming
heightmap
outlook-api
node-sass
boost-multi-index
ionicons
alphabet
tizen-native-app
rdfs
sqlclient
hittest
synchronous
topbeat
xcb
android-fonts
trash
pcf
testng-dataprovider
asp.net5
two-factor-authentication
historian
unity-networking
jms2
atk4
sframe
cakephp-3.1
graph-api-explorer
notify
qpainter
android-imagebutton
socketexception
markers
sgen
ccss
easy-install
eventual-consistency
cassini-dev
armcc
jspinclude
jquery-ui-layout
rfc1123
appendto
krl
mysql-error-1005
blitz++
dmx512
gamma
mozilla-prism
mirah
bespin
database-management
nintendo-ds
simpletest
wsdl.exe

Resources

Mobile Apps Dev
Database Users
javascript
java
csharp
php
android
MS Developer
developer works
python
ios
c
html
jquery
RDBMS discuss
Cloud Virtualization
Database Dev&Adm
javascript
java
csharp
php
python
android
jquery
ruby
ios
html
Mobile App
Mobile App
Mobile App