EXPRESSION

Abstract

The main motto of this PPT is How to use Expression Filter in our applications.

Introduction

  Expression Filter filters against a range of expressions.

Example

.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" version="EE-3.4.0" 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.xsdhttp://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsdhttp://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd"> <flow name="ExpressionFilterFlow1" doc:name="ExpressionFilterFlow1"> <http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8093" path="ExpressionFilter" doc:name="HTTP"/> <logger message="--Entered into the flow" level="INFO" doc:name="Logger"/> <set-payload value="Hello World" doc:name="Set Payload"/> <expression-filter expression="#[message.payload != 'Hello']" doc:name="Expression"/> <logger message="--Success" level="INFO" doc:name="Logger"/> </flow></mule>

Output:INFO 2015-12-13 10:08:59,848 [[ExpressionFilter].config.change.2.thread.1] org.mule.DefaultMuleContext: *********************************************************************** Application: ExpressionFilter ** OS encoding: Cp1252, Mule encoding: UTF-8 ** ** Agents Running: ** Clustering Agent ** JMX Agent ***********************************************************************INFO 2015-12-13 10:08:59,849 [[ExpressionFilter].config.change.2.thread.1] org.mule.module.launcher.MuleDeploymentService: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Started app 'ExpressionFilter' +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++INFO 2015-12-13 10:09:04,493 [[ExpressionFilter].connector.http.mule.default.receiver.02] org.mule.api.processor.LoggerMessageProcessor: --Entered into the flowINFO 2015-12-13 10:09:04,507 [[ExpressionFilter].connector.http.mule.default.receiver.02] org.mule.api.processor.LoggerMessageProcessor: --Success

Flow of execution:1. URL to trigger the service from browserhttp://localhost:8093/ExpressionFilter 2. Expression filter checks whether the given payload not equal to ‘Hello’ or not?, if yes, it will print a message ‘Success’, else it will not go further.

References

https://docs.mulesoft.com/mule-user-guide/v/3.7/filters