Chapter 29. Ruby

Ruby is a dynamic, open source programming language with a focus on simplicity and productivity. It has an elegant syntax that is natural to read and easy to write. The Ruby support is part of the camel-script module.

To use Ruby in your routes you need to add a dependency on camel-script to your project as shown in Example 29.1, “Adding the camel-script dependency”.

<!-- Maven POM File -->
...
<dependencies>
  ...
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-script</artifactId>
    <version>${camel-version}</version>
  </dependency>
  ...
</dependencies>

To use the ruby() static method in your application code, include the following import statement in your Java source files:

import static org.apache.camel.builder.script.ScriptBuilder.*;

Table 29.1, “Ruby attributes” lists the built-in attributes that are accessible when using Ruby.

The attributes all set at ENGINE_SCOPE.

Example 29.2, “Route using Ruby” shows a route that uses Ruby.

<camelContext>
  <route>
    <from uri="direct:start"/>
    <choice>
      <when>
        <langauge langauge="ruby">$request.headers['user'] == 'admin'</langauge>
        <to uri="seda:adminQueue"/>
      </when>
      <otherwise>
        <to uri="seda:regularQueue"/>
      </otherwise>
    </choice>
  </route>
</camelContext>

To access a property value from the properties component, invoke the resolve method on the built-in properties attribute, as follows:

.setHeader("myHeader").ruby("properties.resolve(PropKey)")

Where PropKey is the key of the property you want to resolve, where the key value is of String type.

For more details about the properties component, see Properties in the Apache Camel Component Reference Guide.