Reading Attachments in Mule
This article takes a look at reading attachments in Mule and also explores the configuration as well as the attachment metadata.
Join the DZone community and get the full member experience.
Join For Free
Let's say there is a requirement to handle a multipart request. As the request is received by Mule, the attachments are saved in an object called InboundAttchments, which is part of Mule Message.
Configuration
- Create a Mule flow with an HTTP listener.
- First, to read the total attachments received. Drop a logger after HTTP and write
#[message.inboundAttachments.size()]
in the logger message. - To read the contents of attachment(s). Add a For Each. It will loop over the inbound Attachments object and read them one by one. Give
#[message.inboundAttachments]
against collection in properties tab. - Inside the For Each scope, place a logger to read the contents using
#[message.payloadAs(java.lang.String)]
. Reading the payload using#[payload]
will return an object.
Getting Attachment Metadata
- Attachment Name To get the name of attachment, we can use the variable key, which is auto-generated by Mule inside the For Each scope
#[flowVars.key]
or#[payload.dataSource.part.fileName]
- Attachment size (in Bytes) To get the attachment size, we have to read the payload and use the getBytes method
#[message.payloadAs(java.lang.String).getBytes().length]
or#[payload.dataSource.part.size]
- Content Type To get the content type of the attachment:
#[payload.dataSource.part.contentType]
Flow XML
<?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="0.0.0.0" port="8081" doc:name="HTTP Listener Configuration" />
<flow name="attachmentFlow">
<http:listener config-ref="HTTP_Listener_Configuration"
path="/attachment" doc:name="HTTP" />
<logger
message="Total Attachments: #[message.inboundAttachments.size()]"
level="INFO" doc:name="Total Attachments" />
<foreach collection="#[message.inboundAttachments]" doc:name="For Each">
<logger
message="#["Attachment Name: " +flowVars.key+"\nAttachment Size (in Bytes): "+payload.dataSource.part.size +"\nContent-Type: "+payload.dataSource.part.contentType+"\nAttachmant Data: "+message.payloadAs(java.lang.String)]"
level="INFO" doc:name="Attachment Details" />
</foreach>
</flow>
</mule>
Thanks, and let me know your thoughts in the comments section!
Object (computer science)
Requests
Payload (computing)
Flow (web browser)
Metadata
Requirement
Drops (app)
XML
Opinions expressed by DZone contributors are their own.
Comments