ESB braindump

ESB braindump.md

ESB

An Enterprise Service Bus (ESB) is fundamentally an architecture. It is a set of rules and principles for integrating numerous applications together over a bus-like infrastructure.

Agile Integration

The approach that allows those microservices to be droppped into the architecture seamlessly or to be removed or updated without distrupting other services.

3 Pillars of Agile Integration

1. Distributed Integration (Flexibility) - 3 types
   1. Fuse on KARAF
   2. Fuse on EAP
   3. Fuse on Spring Boot
2. microServices Containers (Scalability)
3. API's (Re-Usability)

Red Hat Fuse

An open source integration platform based on Apache Camel

3 Product Distributions for Fuse 7.x

1. Fuse Standalone (Classic Integration)
2. Fuse on OpenShift (Cloud Native Integration)
3. Fuse Online - iPaas (Ad Hoc Integration)

Apache Camel

A versatile open-source integration framework based on known Enterprise Integration Patterns (EIP).

Apache Camel supports two alternative Domain Specific Languages (DSL) for defining routes: a Java DSL and a Spring XML DSL. The basic building blocks for defining routes are endpoints and processors, where the behavior of a processor is typically modified by expressions or logical predicates.

1. camel-examples
2. Data Transformation: XML to JSON And JSON to XML

Apache Maven

A tool that can now be used for building and managing any java-based project, and it is based in POM (Project Object Model)

POM

A building bock in maven, it is a xml file which constains information and configuration of the project like defendencies and goals.

CodeReady Studio

A set of Eclipse-based development tools. It contains plug-ins that integrate with Eclipse to extend the existing functinality of the integrated development environment (IDE).

Issues and Solutions

• log4j:WARN No appenders could be found for logger (org.eclipse.aether.internal.impl.DefaultLocalRepositoryProvider). log4j:WARN Please initialize the log4j system properly.

• pom.xml when adding restlet as consumer

  • Missing artifact org.restlet.jee:org.restlet:jar:2.3.12 Maven Repo
    • Solution: add entries below on pom.xml above </dependecies>

      <!-- https://mvnrepository.com/artifact/org.restlet.jee/org.restlet -->
      <dependency>
        <groupId>org.restlet.jee</groupId>
        <artifactId>org.restlet</artifactId>
        <version>2.3.12</version>
      </dependency>
      

  • Missing artifact org.restlet.jee:org.restlet.ext.httpclient:jar:2.3.12 Maven Repo
    • Solution: add entries below on pom.xml above </dependecies>

      <!-- https://mvnrepository.com/artifact/org.restlet.jee/org.restlet.ext.httpclient -->
      <dependency>
        <groupId>org.restlet.jee</groupId>
        <artifactId>org.restlet.ext.httpclient</artifactId>
        <version>2.3.12</version>
      </dependency>
      

  • Additonal step aside from the two above dependecies, add entries below on pom.xml below <repositories>

    <!-- https://mvnrepository.com/artifact/org.restlet.jee/org.restlet and org.restlet.ext.httpclient -->
    <repository>
      <id>maven.restlet.org</id>
      <name>maven.restlet.org</name>
      <url>http://maven.restlet.org</url>
    </repository>
    

  • Run on fuse console

    admin@root()> features:install camel-restlet
    

    • To solved below issues;
      • fuse console

        246 │ GracePeriod │  80 │ 1.0.0.SNAPSHOT                  │ Empty Camel Blueprint Exam
        

      • /fuse-karaf-7.6.0.fuse-760025-redhat-00001/data/log/fuse.log

        INFO  | FelixStartLevel      | o.a.a.b.c.BlueprintContainerImpl | 51 - org.apache.aries.blueprint.core - 1.10.2 | Blueprint bundle blueprint-restlet-api/1.0.0.SNAPSHOT is waiting for dependencies [(&(component=restlet)(objectClass=org.apache.camel.spi.ComponentResolver))]
        

• blueprint.xml - No grammar constraints (DTD or XML Schema) referenced in the document.

  • Solution: Just Ignore the Warnings => https://www.programmersought.com/article/20302346083/

pom.xml adjustment for Restlet;
Replace;

  </dependencies>
  <repositories>

With;

	<!-- https://mvnrepository.com/artifact/org.restlet.jee/org.restlet -->
	<dependency>
	  <groupId>org.restlet.jee</groupId>
	  <artifactId>org.restlet</artifactId>
	  <version>2.3.12</version>
	</dependency>
        <!-- https://mvnrepository.com/artifact/org.restlet.jee/org.restlet.ext.httpclient -->
	<dependency>
	  <groupId>org.restlet.jee</groupId>
	  <artifactId>org.restlet.ext.httpclient</artifactId>
	  <version>2.3.12</version>
	</dependency>
  </dependencies>
  <repositories>
	<!-- https://mvnrepository.com/artifact/org.restlet.jee/org.restlet and org.restlet.ext.httpclient -->
	<repository>
	  <id>maven.restlet.org</id>
	  <name>maven.restlet.org</name>
	  <url>http://maven.restlet.org</url>
       </repository>