How can to create a JavaScript Hello World in a Mule component

Question

I am trying to build a simple script inside a Mule component but I can't seem to find any documentation on how to get me started.

The JavaScript Component Reference shares no ideas on how to get something simple to run.

Answer 1

Here is a simple example:

You send a JSON encoded array and the script will return you the sum. Simple!

There is the flow:

<flow name="calculateFlow1" doc:name="calculateFlow1">
    <http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8089" doc:name="HTTP"/>
    <byte-array-to-string-transformer doc:name="Byte Array to String"/>
    <scripting:component doc:name="JavaScript">
        <scripting:script engine="JavaScript">
            <scripting:text><![CDATA[
                var a = eval('(' + payload + ')');
                for (var i = 0, sum = 0; i < a.length; sum += a[i++]);
                message.setPayload(sum + "");
                result = message;
        ]]></scripting:text>

        </scripting:script>
    </scripting:component>
</flow>

Variables already given by Mule: message, payload.