Skip to content

Content Enricher

This page explains how you can implement a sample scenario of the Content Enricher EIP using the WSO2 Micro Integrator.

Introduction to Content Enricher

The Content Enricher EIP facilitates communication with another system if the message originator does not have all the required data items available. It accesses an external data source to augment a message with missing information.

Info

For more information, see the Content Enricher documentation.

Data enricher

Sample scenario

This example scenario depicts a stock quote service. The client sends a stock quote request to the WSO2 MI with only an identity number. But to provide a stock quote, the sample Axis2 server at the backend needs to map the identity number with a corresponding name, which is in an external source. The values are stored as local entries. When the request arrives, the identity will be analyzed using the Switch mediator. Sequentially, the identity number will be replaced with the local entry using the Enrich mediator.

The diagram below depicts how to simulate the example scenario using the WSO2 MI.

Content enricher

Before digging into implementation details, let's take a look at the relationship between the example scenario and the Content Enricher EIP by comparing their core components.

Content Enricher EIP Content Enricher Sample Scenario
Basic Message Stock Quote Request from Stock Quote Client
Enricher Enrich Mediator
Resource Local Registry
Enriched Message Enriched Stock Quote Request from the WSO2 MI

Synapse configuration of the artifacts

Given below is the synapse configuration of this sample.

<?xml version="1.0" encoding="UTF-8"?>
<proxy name="ContentEnrichProxy" startOnLoad="true" transports="http https" xmlns="http://ws.apache.org/ns/synapse">
    <target>
        <inSequence>
            <switch source="//m1:symbol" xmlns:m1="http://services.samples/xsd">
                <case regex="1">
                    <enrich description="">
                        <source clone="true" key="Location1" type="inline"/>
                        <target action="replace" xpath="//m1:symbol/text()" xmlns:m1="http://services.samples/xsd"/>
                    </enrich>
                </case>
                <case regex="2">
                    <enrich description="">
                        <source clone="true" key="Location2" type="inline"/>
                        <target action="replace" xpath="//m1:symbol/text()" xmlns:m1="http://services.samples/xsd"/>
                    </enrich>
                </case>
                <default></default>
            </switch>
            <call>
                <endpoint key="SimpleStockEp"/>
            </call>
            <respond/>
        </inSequence>
        <faultSequence/>
    </target>
</proxy>

<?xml version="1.0" encoding="UTF-8"?>
<localEntry key="Location1" xmlns="http://ws.apache.org/ns/synapse">
    <![CDATA[IBM]]>
</localEntry>

<?xml version="1.0" encoding="UTF-8"?>
<localEntry key="Location2" xmlns="http://ws.apache.org/ns/synapse">
    <![CDATA[WSO2]]>
</localEntry>

<?xml version="1.0" encoding="UTF-8"?>
<endpoint name="SimpleStockEp" xmlns="http://ws.apache.org/ns/synapse">
    <address uri="http://localhost:9000/services/SimpleStockQuoteService">
        <suspendOnFailure>
            <initialDuration>-1</initialDuration>
            <progressionFactor>1</progressionFactor>
        </suspendOnFailure>
        <markForSuspension>
            <retriesBeforeSuspension>0</retriesBeforeSuspension>
        </markForSuspension>
    </address>
</endpoint>

Let's investigate the elements of the configuration in detail. - enrich - The enrich mediator is used for message enrichment. In this configuration, it retrieves content from a local registry entry (via source) and replaces certain elements in the message (via target). - source - The source element in the enrich mediator defines where the content for enrichment originates. The location in which you can find the source configuration. In this example, it is a simple inline text string located in the local registry entry. - target - The target element in the enrich mediator specifies where the source configuration should be applied. This is specified using an XPath expression. - localEntry - The localEntry element represents entries in the local registry. In this example, Location1 contains IBM, and Location2 contains WSO2.

Set up the sample scenario

Follow the below instructions to simulate this sample scenario.

  1. Install WSO2 Micro Integrator.

    Info

    Follow the Install the Micro Integrator Runtime documentation for more information.

  2. Launch Visual Studio Code with the Micro Integrator for VS Code extension (MI for VS Code) installed.

    Info

    Follow the Install Micro Integrator for VS Code documentation for a complete installation guide.

  3. Download the backend service.

  4. Extract the downloaded zip file.

  5. Open a terminal, and navigate to the axis2Server/bin/ directory inside the extracted folder.

  6. Execute the following command to start the axis2server with the SimpleStockQuote backend service:

    sh axis2server.sh

    axis2server.bat

  7. Download the artifacts of the sample.

    Download ZIP

  8. Import the artifacts to WSO2 MI.

    Click File -> Open Folder -> Select the extracted ZIP file to import the downloaded ZIP file.

  9. Start the project in the WSO2 MI server.

    For instructions, go to Build and Run Documentation.

Execute the sample

Send the following request to the above proxy service.

POST /services/ContentEnrichProxy HTTP/1.1
Host: localhost:8290
Content-Type: text/xml
soapAction: urn:getQuote

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://services.samples" xmlns:xsd="http://services.samples/xsd">
   <soapenv:Header/>
   <soapenv:Body>
      <ser:getQuote>
         <ser:request>
            <xsd:symbol>2</xsd:symbol>
         </ser:request>
      </ser:getQuote>
   </soapenv:Body>
</soapenv:Envelope>

Analyze the output

A message similar to the one below appears in the simple axis2server.

Tue Aug 13 21:10:16 IST 2024 samples.services.SimpleStockQuoteService :: Generating quote for : WSO2

You can view the response as follows.

<?xml version='1.0' encoding='UTF-8'?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
    <soapenv:Header/>
    <soapenv:Body>
        <ns:getQuoteResponse xmlns:ns="http://services.samples">
            <ns:return xmlns:ax21="http://services.samples/xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="ax21:GetQuoteResponse">
                <ax21:change>-2.8978741189955097</ax21:change>
                <ax21:earnings>-9.939907930800844</ax21:earnings>
                <ax21:high>-158.8567947828041</ax21:high>
                <ax21:last>162.024543774764</ax21:last>
                <ax21:lastTradeTimestamp>Tue Aug 13 21:10:16 IST 2024</ax21:lastTradeTimestamp>
                <ax21:low>-158.4099442705978</ax21:low>
                <ax21:marketCap>3.952813978268175E7</ax21:marketCap>
                <ax21:name>WSO2 Company</ax21:name>
                <ax21:open>168.644570459495</ax21:open>
                <ax21:peRatio>-18.634969373595844</ax21:peRatio>
                <ax21:percentageChange>-1.590623198106395</ax21:percentageChange>
                <ax21:prevClose>182.18482683047569</ax21:prevClose>
                <ax21:symbol>WSO2</ax21:symbol>
                <ax21:volume>18487</ax21:volume>
            </ns:return>
        </ns:getQuoteResponse>
    </soapenv:Body>
</soapenv:Envelope>