Message Enricher in Mule

  Message Enricher in Mule

One common scenario involves the need to enrich an incoming message with information that isn’t provided by the source system. You can use a content enricher if the target system needs more information than the source system can provide.

Consider a message from a source system contains a zip code but the target system needs the two letter state. A message enricher can be used to lookup the state using the zip code from an enrichment resource. The enricher calls out to the enrichment resource with the current message (containing the zip code) then enriches the current message with the result.

This is a very simple flow with one-way inbound and outbound endpoints, and which acts as part of an order processing pipeline. This flow uses an enricher to add a state flow variable to the current message with the state that the stateLookup endpoint returns. The ‘target’ attribute defines how the current message is enriched using a MessageEnricher which uses the same syntax as expression evaluators.


Here we are using Message Enricher in mule 3 in Anypoint studio 6.2

Message Enricher modifies some part of payload without affecting whole payload.

for eg. if i have 3 attributes id, name and age and name and i want to modify the attribute name from the value coming from database then in this case we can use message enricher.

We are using MYSQL db with same schema and table that i used in database connector tutorial.

Here is flow of message enricher, We are giving input by POST request which transformed into java array by transform message 1 and then message enricher modifies original payload by database output provided bt transform message 2.


sublow is connected by main flow via flow reference.




There are two main fields are there in message enricher : Source & Target

Source : It is the attribute or data which will merge with original payload like in our case NAME attribute coming from db is Source.


Target : It is the attribute which will change. Like in our case name attribute of original payload.

path : /message

url : http://localhost:8085/api/message

method : POST

 input :

Output :

Project XML code :


<?xml version="1.0" encoding="UTF-8"?>
<mule xmlns:db="http://www.mulesoft.org/schema/mule/db" xmlns:metadata="http://www.mulesoft.org/schema/mule/metadata" xmlns:json="http://www.mulesoft.org/schema/mule/json" xmlns:tracking="http://www.mulesoft.org/schema/mule/ee/tracking"
xmlns:dw="http://www.mulesoft.org/schema/mule/ee/dw" xmlns:http="http://www.mulesoft.org/schema/mule/http"
xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation"
xmlns:spring="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
http://www.mulesoft.org/schema/mule/ee/dw http://www.mulesoft.org/schema/mule/ee/dw/current/dw.xsd
http://www.mulesoft.org/schema/mule/ee/tracking http://www.mulesoft.org/schema/mule/ee/tracking/current/mule-tracking-ee.xsd
http://www.mulesoft.org/schema/mule/db http://www.mulesoft.org/schema/mule/db/current/mule-db.xsd
http://www.mulesoft.org/schema/mule/json http://www.mulesoft.org/schema/mule/json/current/mule-json.xsd">
    <http:listener-config name="HTTP_Listener_Configuration" host="0.0.0.0" port="8085" basePath="/api" doc:name="HTTP Listener Configuration"/>
    <db:mysql-config name="MySQL_Configuration" host="localhost" port="3306" user="root" password="********" database="demodata" doc:name="MySQL Configuration"/>
<flow name="mainFlow">
<http:listener config-ref="HTTP_Listener_Configuration"
path="/message" doc:name="HTTP" />
        <dw:transform-message metadata:id="bc275a92-358b-44ae-8e1b-04c92d823991" doc:name="Transform Message 1">
            <dw:input-payload mimeType="application/json"/>
            <dw:set-payload><![CDATA[%dw 1.0
%output application/java
---
payload map ((payload01 , indexOfPayload01) -> {
name: payload01.name,
age: payload01.age,
city: payload01.city
})]]></dw:set-payload>
        </dw:transform-message>

        <foreach doc:name="For Each">
            <enricher doc:name="Message Enricher">
                <flow-ref name="subFlow" doc:name="subFlow"/>
                <enrich source="#[payload.NAME]" target="#[payload.name]"/>

            </enricher>
        </foreach>
        <json:object-to-json-transformer doc:name="Object to JSON"/>
        <set-payload value="#[payload]" doc:name="Set Payload"/>

</flow>
<sub-flow name="subFlow">
        <db:select config-ref="MySQL_Configuration" doc:name="Database">
            <db:parameterized-query><![CDATA[select NAME from info where ID=1]]></db:parameterized-query>
        </db:select>
        <dw:transform-message doc:name="Transform Message 2">
            <dw:set-payload><![CDATA[%dw 1.0
%output application/java
---
{
NAME : payload[0].NAME
}]]></dw:set-payload>
        </dw:transform-message>
</sub-flow>
</mule>