12 Useful list of Predefined variables in Dataweave MuleSoft

List of predefined variables in Dataweave of Mule 4

Here is the list of predefined variables in Dataweave. You cannot use these variables in your Mule event for any other purposes. This list of predefined variables in mule 4 gives us useful information on Mule event, message, server, and others.

app

The Mule artifact in context.

Example: #[app.name] might return your application name.

flow (Deprecated)

The name of the current flow. Because flow names are static, this field is deprecated and only available through the Logger component.

Example: #[flow.name] returns sample_flowName in the Studio console when executed within a Flow with the name sample_flowName.

payload

It gives you the body of the current Mule message object (message) being processed.

Example: #[payload] returns the body of the message.

vars

All variables currently set on the current Mule event flow being processed.

Example: #[vars.varName] returns the value of varName.

attributes

Attributes (metadata) of a Mule Message object (message).

Example: #[attributes] returns message attributes. For an HTTP request, #[attributes.queryParams] returns HTTP queryParams metadata, and #[attributes.version] returns HTTP/1.1

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authentication

Provides access to the authentication information of the Mule application.

Example: #[authentication.properties]

correlationId

The correlationId of the message being processed.

Example: #[correlationId] might return e-fdfjd-324f204-545345-cer34f-323fd3.

dataType

Data type of the message payload.

Example: #[dataType] might return SimpleDataType.

error

Error associated with a Mule message object.

Example: #[error.errorMessage]

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mule 

The Mule instance on which the application is currently running.

Example: #[mule.version] might return 4.3.0.

message

Package (payload and attributes) being processed.

Example: #[message] returns attributes along with the payload

server

The operating system on which the Mule instance is running. Reveals information about both the physical server and the JVM on which Mule runs.

Example: #[server.timeZone] might returns server's timezone