Mule Integration
There are two primary ways you can use MQL inside of Mule.
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Transformations - the <mql:transform> element allows you to perform a filter/join/transformation in a flow.
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Query service - the <mql:query-service> element easily builds a RESTful service for you from a query
When using MQL inside of Mule, there are several special variables you can use:
| Name | Description |
|---|---|
payload |
The current Mule message payload |
mule |
An object that allows you to do joins using mule endpoints. |
Any message property name |
Refer to any message property inline. For example, from payload where SomeProperty = 'foo' |
To use the Mule integration, be sure to declare the MQL namespace in your Mule config file:
<?xml version="1.0" encoding="UTF-8"?><mule xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:spring="http://www.springframework.org/schema/beans" xmlns:mql="http://www.mulesoft.org/schema/mule/mql" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/3.1/mule.xsd http://www.mulesoft.org/schema/mule/mql http://www.mulesoft.org/schema/mule/mql/3.1/mule-mql.xsdTransformations
The <mql:transform> element allows you to perform a filter/join/transformation in a flow. For example:
<mql:transform query="from payload as p select new { name = p.firstName + ' ' + p.lastName }" />The <mql:transform> element takes an optional type argument which specifies how you want to process the Mule payload.
| Type | Description |
|---|---|
POJO |
The input type is a POJO that requires no transformation |
JSON |
The input type is JSON and should be transformed into a set of objects MQL can recognize. |
AUTO |
Auto detect the input type based on the Content-Type header and the data type of the Mule payload. This is the default value. |
For example:
<mql:transform type="POJO" query="from payload as p select new { name = p.firstName + ' ' + p.lastName }" />Query service
The <mql:query-service> element easily builds a Mule service for you on a particular endpoint. With this, you can easily build RESTful JSON services. For example, this will query an object and return the data as JSON:
<mql:query-service name="Users" address="http://localhost:9002/users" query="from userManager.users as user select new { name = user.name, email = user.email, company = sfuser[0].?Company, mobile = sfuser[0].?MobilePhone }"/>You can also build services which process POJOs:
<mql:query-service name="Users" address="vm://users" type="POJO" query="from userManager.users as user select new { name = user.name, email = user.email, company = sfuser[0].?Company, mobile = sfuser[0].?MobilePhone }"/>Mule Client
Sometimes, you want to query an endpoint for data within a query. You can do this as part of a from statement or a join. For example, this query will join data from an endpoint:
<flow name="join"> <inbound-endpoint address="vm://join" exchange-pattern="request-response" /> <mql:transform query="from payload as p join mule.send('vm://locationService', p.geoIp) as location select new { name = firstName + ' ' + lastName, location = location }" /></flow>This code will query the vm://locationService endpoint with the property "geoIp" on each object. The result will be stored in the location variable for use in the select statement.