ReadMessage - 6.3

Talend Data Mapper User Guide

EnrichVersion
6.3
EnrichProdName
Talend Big Data Platform
Talend Data Fabric
Talend Data Management Platform
Talend Data Services Platform
Talend MDM Platform
Talend Real-Time Big Data Platform
task
Design and Development
EnrichPlatform
Talend Studio

Name

ReadMessage

Purpose

Reads a message from an enclosing ESB into a map element.

Description

The ReadMessage function may be used only as an I/O expression. Specify it as the I/O expression of the element to contain the data to be read. The contents of message are read during the map execution populating the values of the element containing the I/O expression and any subordinate elements.

Reading Message Properties - if you want to access properties that are associated with the message, they can be read into map elements. To do this the first child map element must specify the ReadMessageProperties I/O function, inherit from the /Builtin/Structures/Properties structure, and must be a loop. When the message is read, the property elements of this structure are populated with the property names and values.

You may use this function in multiple map elements in order to read multiple messages. You may not however nest the use of this function. In other words, if a map element contains an I/O expression, no subordinate map element may contain an I/O expression. See the discussion on Input/Output for further details.

Return Type

N/A (this function may be used only as an I/O expression)

Property

Representation

The representation type to select when processing this message. This is used if multiple representations are available in the structure controlling the I/O (the structure inheriting this element).

Property

Endpoint

The endpoint name that is meaningful to the enclosing ESB to identify where to get the message.

Property

Offset

The byte offset into the contents to start reading at. If not specified, 0 is assumed.

Property

Length

The number of bytes of content to read. If not specified all of the bytes are read.

Argument

Offset (Integer)

The byte offset into the contents to start reading at. If not specified, 0 is assumed.

Argument

Length (Integer)

The number of bytes of content to read. If not specified all of the bytes are read.