The Mock component in MUnit allows you to define mocked behavior for a message processor. You can modify how a specific message processor responds when called with particular attributes. The example shows using Mock to replace the "Set Payload" processor with one that returns "Good Morning!" instead of "Hi", and asserting the payload is now "Good Morning!".

1. How to use Mock component in
MUnit
04-04-2017

2. Abstract
• The Mock feature provided by MUnit allows
you to define mocked behavior for a message
processor. In this case, MUnit replaces the
normal behavior of the message processor
with the behavior you define. Thus you can
modify how a specific message processor
responds when it is called with a particular set
of attributes.

4. • .mflow
• <?xml version="1.0" encoding="UTF-8"?>
• <mule 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:listener-config name="HTTP_Listener_Configuration" host="localhost" port="8089"
doc:name="HTTP Listener Configuration"/>
• <flow name="MockFlow">
• <http:listener config-ref="HTTP_Listener_Configuration" path="/" doc:name="HTTP"/>
• <set-payload value="Hi" doc:name="Set Payload"/>
• <logger message="------#[payload]----" level="INFO" doc:name="Logger"/>
• </flow>
• </mule>

6. • <?xml version="1.0" encoding="UTF-8"?>
• <mule xmlns:mock="http://www.mulesoft.org/schema/mule/mock" xmlns="http://www.mulesoft.org/schema/mule/core"
xmlns:doc="http://www.mulesoft.org/schema/mule/documentation" xmlns:munit="http://www.mulesoft.org/schema/mule/munit"
xmlns:spring="http://www.springframework.org/schema/beans" xmlns:core="http://www.mulesoft.org/schema/mule/core"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.mulesoft.org/schema/mule/munit
http://www.mulesoft.org/schema/mule/munit/current/mule-munit.xsd
• 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/mock http://www.mulesoft.org/schema/mule/mock/current/mule-mock.xsd">
• <munit:config name="munit" doc:name="MUnit configuration"/>
• <spring:beans>
• <spring:import resource="classpath:Mock.xml"/>
• </spring:beans>
• <munit:test name="Mock-test-suite-MockFlowTest" description="Test">
• <mock:when messageProcessor=".*:.*" doc:name="Mock">
• <mock:with-attributes>
• <mock:with-attribute name="doc:name" whereValue="#['Set Payload']"/>
• </mock:with-attributes>
• <mock:then-return payload="Good Morning!"/>
• </mock:when>
• <flow-ref name="MockFlow" doc:name="MockFlow"/>
• <munit:assert-on-equals expectedValue="Good Morning!" actualValue="#[payload]" doc:name="Assert Equals"/>
• </munit:test>
• </mule>

7. • Output:

8. • Reference:
https://docs.mulesoft.com/munit/v/1.1.1/mock
-message-processor