camel-spring-boot-course

Project for course about Apache Camel + Spring Boot.

OBS: In case that don’t work, check routes with .noAutoStartup() pipeline or with @Component commented

Camel is an Open Source integration framework that empowers you to quickly and easily integrate various systems consuming or producing data.

Topic Reference	Reference
Why Camel?	https://camel.apache.org/manual/latest/faq/why-the-name-camel.html
Camel Examples	https://github.com/apache/camel-examples/tree/master/examples
Camel Spring Boot Configuration	https://camel.apache.org/camel-spring-boot/latest/spring-boot.html
Complete Spring Boot Starters List	https://camel.apache.org/camel-spring-boot/latest/list.html
Camel Spring Boot Examples	https://github.com/apache/camel-spring-boot-examples
Enterprise Integration Patterns	https://camel.apache.org/components/latest/eips/enterprise-integrationpatterns.html

Apache Camel

Architecture:

• Camel Context
  • Endpoint: Reference to a queue, database or file
  • Route: Endpoints + Processor(s) + Transformer(s)
  • Components: Extensions (Kafka, JSON, JMS, etc)
  • Transformation
    • Data format transformation: XML to JSON
    • Data type transformation: String to CurrencyConversionBean
• Message: Body + Headers + Attachments
• Exchange: Request + Response
  • Exchange ID
  • Message Exchange Pattern (MEP): InOnly/InOut
  • Input Message and (optional) Output Message

Integration Examples

Some examples

Active MQ

• add dependency to project:

  <dependency>
    <groupId>org.apache.camel.springboot</groupId>
    <artifactId>camel-activemq-starter</artifactId>
    <version>${camel.version}</version>
  </dependency>
  

• run docker run -p 61616:61616 -p 8161:8161 rmohr/activemq
• add to file application.properties: spring.activemq.broker-url=tcp://localhost:61616
• interface access: http://localhost:8161 with user/password -> admin/admin

Kafka

• add dependency to project:

  <dependency>
    <groupId>org.apache.camel.springboot</groupId>
    <artifactId>camel-kafka-starter</artifactId>
    <version>${camel.version}</version>
  </dependency>
  

• use the ./docker-compose.yaml file
• run docker-compose up on docker-compose directory
• add to file application.properties: camel.component.kafka.brokers=localhost:9092
• edit /etc/hosts and add unknown host created. Ex: 127.0.0.1 458077ddabfc

Rest API

• add dependency to project:

  <dependency>
    <groupId>org.apache.camel.springboot</groupId>
    <artifactId>camel-http-starter</artifactId>
    <version>${camel.version}</version>
  </dependency>
  

• create class with @RestController in service B and add config restConfiguration().host("localhost").port(8000);
• create class RestApiRoute.java in service A with to("rest:METHOD:/PATH")

Examples Routes / Controllers / Processors / Beans / Strategies

Microservice A

• ActiveMqSenderRouter
• AggregateRouter
• DynamicRoutingRouter
• FileRouter
• KafkaSenderRouter
• MulticastRouter
• RestApiRouter
• RoutingSlipRouter
• SplitRouter
• TimerRouter

Microservice B

• ActiveMqReceiverRouter
• KafkaReceiverRouter

Creating Key Store

Command to create:

keytool -genseckey -alias myDesKey -keypass someKeyPassword -keystore myDesKey.jceks -storepass someKeystorePassword -v -storetype JCEKS -keyalg DES

OBS: put myDesKey.jceks in your src/main/resources directory

Crypto data class: MyCryptoData