Async Scope in Mule






Async Scope in Mule


The Async scope is a branch processing block that executes simultaneously with the main flow. The main flow continues to execute while it initiates and processes the Async scope. The flow does not have to pause until the last message processor embedded in the asynchronous flow has completed its task.

Async can be useful for executing time-consuming operations that do not require you to send a response back to the initiating flow (such as printing a file or connecting to a mail server).

To facilitate simultaneous branch processing, the Async scope sends one copy of the message it has received to the first embedded message processor in its own processing block. At the same time, it sends another copy of the message to the next message processor in the main flow.


Async scope processes the nested list of message processors asynchronously using a thread pool.

flow of async scope :




Here in above flow, since we applied async scope in subflow it processes asynchronously in a separate thread while parent flow execute in separate thread.
So parent flow will not wait for child flow to execute and continue its processing irrespective of child flow.

URL : http://localhost:8085/api/async

Method : POST

Input :




Output :


Logger output in console :




XML project code :



<?xml version="1.0" encoding="UTF-8"?> <mule xmlns:file="http://www.mulesoft.org/schema/mule/file" xmlns:db="http://www.mulesoft.org/schema/mule/db" xmlns:http="http://www.mulesoft.org/schema/mule/http" xmlns:scripting="http://www.mulesoft.org/schema/mule/scripting" 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/db http://www.mulesoft.org/schema/mule/db/current/mule-db.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/scripting http://www.mulesoft.org/schema/mule/scripting/current/mule-scripting.xsd http://www.mulesoft.org/schema/mule/file http://www.mulesoft.org/schema/mule/file/current/mule-file.xsd"> <http:listener-config name="HTTP_Listener_Configuration" host="0.0.0.0" port="8085" basePath="/api" doc:name="HTTP Listener Configuration"/> <file:connector name="File" writeToDirectory="src/main/resources/child" autoDelete="false" streaming="false" validateConnections="true" doc:name="File"/> <file:connector name="File1" writeToDirectory="src/main/resources/parent" autoDelete="false" streaming="false" validateConnections="true" doc:name="File"/> <flow name="test_asyncFlow"> <http:listener config-ref="HTTP_Listener_Configuration" path="/async" doc:name="HTTP"/> <async doc:name="Async"> <flow-ref name="test_asyncFlow1" doc:name="test_asyncFlow1"/> </async> <file:outbound-endpoint path="src/main/resources/parent" outputPattern="parent.json" connector-ref="File1" responseTimeout="10000" doc:name="File"/> <logger message="Parent flow completed" level="INFO" doc:name="Logger"/> </flow> <flow name="test_asyncFlow1"> <logger message="In Child Flow" level="INFO" doc:name="Logger"/> <scripting:component doc:name="Groovy"> <scripting:script engine="Groovy"><![CDATA[sleep(20000);]]></scripting:script> </scripting:component> <file:outbound-endpoint path="src/main/resources/child" outputPattern="child.json" connector-ref="File" responseTimeout="10000" doc:name="File"/> <logger message="Child flow completed" level="INFO" doc:name="Logger"/> </flow> </mule>