How to access a property in dataweave ?110

 How to access a property in dataweave ?

There are two main ways to access a property in DataWeave:

1. Using the p function:

This is the recommended approach for accessing properties defined in a properties file or retrieved from the Mule application context. The p function belongs to the dw::Mule module, which is imported by default in DataWeave scripts.

Here's the syntax:

<property_value> = p('propertyName')

Example:

%dw 2.0
---
name = p('app.name')
message = "Welcome to " ++ name
---

2. Using context variables:

This method involves storing the property value in a Mule application context variable and then referencing it within your DataWeave script.

Here's a breakdown of the steps:

• Set the Context Variable: In your Mule flow configuration, define a context variable and assign the desired property value to it.

• Access the Variable: Within your DataWeave script, use the variable name to access the stored property value.

Example:

• Flow Configuration:

XML

<flow name="access-property">
  <set-variable value="value of your property" name="myProperty" />
  <transform message="#[payload]" doc:name="DataWeave Transformation">
    <script type="text/mule-dataweave">
      %dw 2.0
      ---
      message = "Value from property: " ++ myProperty
      ---
    </script>
  </transform>
</flow>

• DataWeave Script:

message = "Value from property: " ++ myProperty

Choosing the Right Method:

• p function: This is generally the preferred approach as it directly retrieves the property value without requiring additional configuration within the flow.

• Context variables: This method might be useful if you need to access the property value in multiple places within your flow or perform additional processing on it before using it in DataWeave.

Remember that security best practices dictate avoiding storing sensitive information directly in property files. Consider using secure alternatives like the Mule registry or environment variables for such cases.