LightningMessageChannel (Beta)

Represents the metadata associated with a Lightning Message Channel. A Lightning Message Channel represents a secure channel to communicate across UI technologies (Lightning Web Components, Aura Components, and Visualforce). This type extends the Metadata metadata type and inherits its fullName field.

As a beta feature, LightningMessageChannel is a preview and isn’t part of the “Services” under your master subscription agreement with Salesforce. Use this feature at your sole discretion, and make your purchase decisions only on the basis of generally available products and features. Salesforce doesn’t guarantee general availability of this feature within any particular time frame or at all, and we can discontinue it at any time. LightningMessageChannel is for evaluation purposes only, not for production use. It’s offered as is and isn’t supported, and Salesforce has no liability for any harm or damage arising out of or in connection with it. All restrictions, Salesforce reservation of rights, obligations concerning the Services, and terms for related Non-Salesforce Applications and Content apply equally to your use of this feature. You can provide feedback and suggestions in the Trailblazer Community.

Note

File Suffix and Directory Location

LightningMessageChannel components have the suffix .messageChannel and are stored in the messageChannels folder.

Version

LightningMessageChannel components are available in API version 47.0 and later.

Fields

Field Name	Field Type	Description
description	string	The description of the Lightning Message Channel.
isExposed	boolean	Indicates whether a Lightning Message Channel is exposed to components in other namespaces (`true`) or not (`false`). The default value is `false`. If you set `isExposed` to `true` on a Message Channel that is in a managed package or referenced by another Message Channel component, you cannot change it to `false`. Other orgs or components already rely on your Message Channel, which can cause their code to break.
lightningMessageFields	LightningMessageField[]	A list of message payload fields for a given Lightning Message Channel.
masterLabel	string	Required. The label for a Lightning Message Channel.

LightningMessageField

Represents a message payload field for a given Lightning Message Channel.

Field Name	Field Type	Description
description	string	The description for a Lightning Message Field.
fieldName	string	Required. Unique identifier of the Lightning Message Field.

Declarative Metadata Sample Definition

Here’s a simple example of a LightningMessageChannel component.

1<?xml version="1.0" encoding="UTF-8"?>
2<LightningMessageChannel xmlns="http://soap.sforce.com/2006/04/metadata">
3    <masterLabel>SampleMessageChannel</masterLabel>
4    <isExposed>true</isExposed>
5    <description>This is a sample Lightning Message Channel.</description>
6</LightningMessageChannel>

The following is an example of a LightningMessageChannel component with LightningMessageFields.

1<?xml version="1.0" encoding="UTF-8"?>
2<LightningMessageChannel xmlns="http://soap.sforce.com/2006/04/metadata">
3    <masterLabel>SampleMessageChannel</masterLabel>
4    <isExposed>true</isExposed>
5    <description>This is a sample Lightning Message Channel.</description>
6    <lightningMessageFields>
7        <fieldName>recordId</fieldName>
8        <description>This is the record Id that changed</description>
9    </lightningMessageFields>
10    <lightningMessageFields>
11        <fieldName>recordData</fieldName>
12        <description>The current data representing the record that changed</description>
13    </lightningMessageFields>
14</LightningMessageChannel>

The following is an example package.xml that references the previous definition.

1<?xml version="1.0" encoding="UTF-8"?>
2<Package xmlns="http://soap.sforce.com/2006/04/metadata">
3    <types>
4        <members>*</members>
5        <name>LightningMessageChannel</name>
6    </types>
7    <version>47.0</version>
8</Package>

Wildcard Support in the Manifest File

This metadata type supports the wildcard character * (asterisk) in the package.xml manifest file. For information about using the manifest file, see Deploying and Retrieving Metadata with the Zip File.

Metadata API Developer Guide