Download - Event Driven Architectures with Camel
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Event Driven Architectures with
Camel
Gnanaguru Sattanathan
Twitter:@gnanagurus
Website: bushorn.com
Prajod Vettiyattil
Twitter: @prajods
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What this session is about
Application Integration
Apache Camel
Event Driven Architectures with Camel
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Application Integration
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Integration
Middleware
JMS, RMI,
JDBC, FTP,
SNMP, TCP
https, SFTP, SNMP,
TCP, CORBA
1. Enterprise Service Bus 2. Integration Framework
1. Validate, Enrich, Route, Transform
2. Diverse protocol support
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The Chameleon
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Camel is a reptile !
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The Chameleon
It can change color with the container
Camel
JVM
Camel
Tomcat
Camel
JBoss
Camel
Websphere
Camel
Oracle
Fusion
Camel
Jetty
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Apache Camel
• Integration framework
• Multiple deployment options
• Feature rich
• Simple to program
• Unique scalability features
• Apache License
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Apache Camel: Components
• More than 100 readymade components
• Covering
– PaaS & Public Clouds
– Social Networks
– Devices
– Almost all standard protocols
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Apache Camel: Components
AWS HDFS
FILE JDBC
AMQP
JMS
MQTT
MongoDB
NETTY
RMI
WebSockets Zoo Keeper
JGroups
ActiveMQ
NMR Smooks
Esper
XSLT
Velocity
Streams
SSH
SQL
TCP
SMTP SMPP SOLR
UDP
XQuery
SIP
SFTP
Cache Hazelcast
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Coding with Camel
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Camel – Code your way
JAVA
SPRING
GROOVY
SCALA
Domain Specific Language
(DSL)
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A simple file integration
File System
Input
Directory
Output
Directory
File
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Simple file integration:
Sample Code
<route>
<from uri="file://d:\Input"/>
<to uri="file://d:\Output"/>
</route>
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using Spring XML
Message Broker
( ActiveMQ)
File System – Message Broker
Integration
File System
Input
Directory
Output
Queue
File
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File System to Message Broker Integration:
Sample Code
<route>
<from uri="file://d:\Input"/>
<to uri="activemq:queue:Output"/>
</route>
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using Spring XML
Tra
nsfo
rmer
Message Broker
( ActiveMQ)
Adding a simple transformation
File System
Input
Directory
Output
Queue
File
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A simple transformation:
Sample Code
<route>
<from uri="file://d:\Input"/>
<to uri="xslt:file://d:\transform.xsl"/>
<to uri="activemq:queue:Output"/>
</route>
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using Spring XML
A simple Twitter application
Message Broker
( ActiveMQ) Twitter.com
Tweets Tweets
Queue
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Tweets
A simple Twitter application:
Sample Code
<route>
<from uri="twitter://search
?type=direct
&keywords=JUDCON”/>
<to uri="activemq:queue:Output"/>
</route>
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Event Driven Architectures with
Camel
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Event Driven Architecture
• EDA • A software architecture pattern • Event: Significant change in state • Parts of the architecture
– Event source – Event channel – Event processor
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EDA
Source
1
Event
Processor 1
Source
2
Event
Processor 2
Source
3
Event
Processor 3
Source
4
Source
5 Source
6 So
urc
es
C
han
nels
P
rocesso
rs
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Staged
Event Driven Architecture(SEDA)
• EDA
– Direct and tight coupling of sources and processors
– Event processor may get swamped with events • Reduces performance • Possible loss of messages
• SEDA – EDA decomposed into stages and connected with
queues
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SEDA: one view
Source
1
Event
Processor 1
Source
2
Event
Processor 2
Source
3
Event
Processor 3
Source
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Source
5 Source
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Channels
Sta
ge 1
C
han
nels
usin
g Q
ueu
es
Sta
ge 2
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SEDA: another view
Source
1
Source
2
Queue Processor
1
Processor
2
Processor
3 Queue
Queue
Stage 2 Channels using
Queues
Stage 1 Channels using
Queues
Stage 3
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SEDA with Camel
• SEDA
– Scalability feature in Camel
– Uses thread pools and internal queues
– Enables parallel processing
– Avoids waiting threads
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Camel with SEDA: comparison
Normalize
Enrich
Split
Route
Waiting thread without SEDA
Th
read 1
Receive Receive
Validate
Normalize
Enrich
Route
Parallel processing with SEDA
Th
read 1
Th
read 2
T
hre
ad 3
SEDA Queue 1
SEDA Queue 2
Split
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Validate
• Impact
– significant reduction in thread
consumption
• For 100 concurrent requests
– Without SEDA: 100 threads; With SEDA: 30 threads
Camel as a part of EDA • Camel as
– Event channel
– Event processor
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Camel
Camel as Event Channel
• SEDA queues
• VM queues
• Multi-threaded flow
• Load balanced flow
• Asynchronous API
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Camel as Event Processor
• Not ideal as the final Event Processor
• Can be used as an intermediate Event processor
• Routing based on events
• Transformation of events
• Combining simple events
• Event auditing, logging
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Camel and the Actor Model
with Akka • Actor Model
– Actors
• Similar to objects, many other features
• Mailbox, behavior/s, internal state
– No shared state
– Messages between actors
– Locking and Threads are abstracted
– Each actor instance runs in its own thread
• Akka-Camel
– Integrate Akka to other applications
– Two way: Akka to Camel and Camel to Akka
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Actor
Mailbox State
Behavior
Summary
• Camel
– Integration Framework
– Simplicity and flexibility
– Components
• EDA with Camel
– SEDA
– SEDA within Camel
– Camel as part of SEDA
• Akka and Camel for EDA
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Questions
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Gnanaguru Sattanathan
Twitter:@gnanagurus
Website: bushorn.com
Prajod Vettiyattil
Twitter: @prajods
Our Open Source Middleware Group on LinkedIn
http://tinyurl.com/be6e93q
