The Blog covers a basic introduction to the tool Apache Camel and its necessary features.
Let us begin with a basic understanding of the need for the tool Apache Camel.
Introduction to Apache Camel
Technically, Apache Camel is an Integration Framework. In order to understand the tool Apache Camel, it is important to understand the concept of Integration first. Integration, in technical terms, refers to moving the data between various systems such as servers, databases, and cloud apps.
How is Integration performed?
Integration requires an understanding of the protocols, data formats, and API(s) of the systems that are required to be connected. Now since it all has to be done manually it turns out to be a very long and tedious task that requires knowledge, time, and manpower. Thus there was a need for an Integration framework that could greatly help in achieving effective integration in a lesser amount of time and effort. That was when the tool Apache Camel came into the picture.
“Apache Camel is an Integration Framework that includes libraries that help in achieving the development and successful run of the integration within Java only, without having a need to write an integration code.”
How is Apache Camel different from other Frameworks?
Apache is one of the best open-source frameworks that provide the following features:
Apache Camel is based on Enterprise Integration Patterns.
It supports the POJO model, used to plug in JavaBeans at various points.
It’s messaging feature allows easy testing of large distributed and asynchronous systems.
Apache Camel has an easy configuration.
It supports both the pluggable data such as JSON, CDV, and EDI as well as pluggable languages such as Python, SQL, XPath, and XQuery.
It provides Rule-based routing and a Mediation Engine.
Apache Camel Architecture
The Apache Camel Architecture includes an Integration Engine and Router, Processors and Components.
The Components module depicted in the camel architecture provides an interface of endpoints to connect external world with the tool. Endpoints further contain their specific URI(s) such as jms: OrderQueue and file:/Order.
The Processors module depicted in the camel architecture helps to manipulate the message and transfer them between the various endpoints and is an essential aspect of the Apache Camel Architecture.
Integration Engine and Router have a set of Processors and Endpoint wired together. Engines use DSL(s) to wire them together . Filters help to filter the message in order to allow user-defined criteria to filter the messages. For writing the integration rules, we may make use of languages such as Java, Scala, Groovy, or XML.
Main Parts that constitute up Apache Camel:
The main parts of the tool are :
An Integration Engine(that runs the integrations).
A Specialized Language(In which integration running instructions are specified like what data to pull or what data to push at a location).
Components(that connect to web services or FTP services or apps.) and other than that there are also some built set of patterns that can be used in integration flows. It is based on enterprise integration patterns.
Components in Apache Camel
Bean Component: The bean component is to used bind beans to camel message exchanges, it contains bean:beanID where beanId is name of bean as specified in the registry.
Direct Component: Direct component synchrornously invokes an endpoint, and helps to basically direct the other parts.
File Component: File component provides an access to the file system.It helps to save messages to a local disk. URI format is either file:directoryName[?options] or file://directoryName[?options].
Log Component: It allows you to log messages to underlying log mechanism. You may use log4j, logback ,java.util.logging for logging.
SEDA Component: It asynchronously calls another endpoint in same CamelContext. In order to call across the CamelContext we make use of VM component.
Timer Component: It sends the messages at regular intervals and is very useful in testing camel applications.You can set interval at which messages are to be sent.
CamelContext in Apache Camel
The Registry module is the JNDI registry which holds the names of various Javabeans that your application uses. if you use camel with OSGI container, then it becomes OSGI registry. If you use Camel in Spring, it will become Spring ApplicationContext.
The Typeconverter contains various loaded type converters that convert the input from one format to another. You may use built in type converters or specify your own type conversions.
The Component module contains components used in the applications, you can load the components by auto-delivery on classpath.
The Data Formats module contains the loaded data formats.
The Language formats module represents the loaded languages.
Routes: The router defines the rule for moving a message to locations. The route begins from an endpoint and finishes at one or more endpoints. you may configure any number of routes within a single configure method.
Conclusion
The blog efficiently discusses the concept of integration, Introduction to Apache camel along with the detailed working of the architecture of Apache Camel. It also describes the components and endpoints involved in the Apache camel, which makes it different from other Integration Frameworks.
References:
To know more about the Apache Camel, you can visit this link: https://camel.apache.org/
To read more tech blogs, feel free to visit https://blog.knoldus.com/