DataWeaveResource Metadata Type for DataWeave in Apex

Why DataWeaveResource Revolutionizes File & Payload Parsing in Apex#

Available starting in API version 58.0, DataWeaveResource (dw/<ScriptName>.dwl and dw/<ScriptName>.dwl-meta.xml) brings MuleSoft’s DataWeave 2.0 transformation language natively into the Apex runtime.

Instead of writing fragile regexes to parse RFC-4180 CSV files with embedded newlines or walking Dom.Document XML trees that exhaust the 10,000-ms Apex CPU limit, you deploy a declarative .dwl script that transforms CSV, JSON, or XML directly into List<SObject> or Apex DTOs.

SFDX Source Format & Metadata Fields#

Each DataWeaveResource consists of two paired files inside force-app/main/default/dw/:

• dw/<ScriptName>.dwl: The DataWeave 2.0 script (%dw 2.0).
• dw/<ScriptName>.dwl-meta.xml: The metadata companion file.

Real-World Example: Transforming CSV directly to Contact SObjects#

1. DataWeave Script (dw/csvToContacts.dwl)#

%dw 2.0
input records application/csv
output application/apex
---
records map(record) -> {
    FirstName: trim(record.first_name),
    LastName: trim(record.last_name),
    Email: lower(trim(record.email)),
    Department: record.dept default "General"
} as Object {class: "Contact"}

2. Metadata Sidecar (dw/csvToContacts.dwl-meta.xml)#

<?xml version="1.0" encoding="UTF-8"?>
<DataWeaveResource xmlns="http://soap.sforce.com/2006/04/metadata">
    <apiVersion>68.0</apiVersion>
    <isGlobal>false</isGlobal>
</DataWeaveResource>

3. Invoking the DataWeaveResource in Apex#

DataWeave.Script script = new DataWeaveScriptResource.csvToContacts();
DataWeave.Result result = script.execute(new Map<String, Object>{
    'records' => csvFileBodyString
});
List<Contact> contactsToUpsert = (List<Contact>) result.getValue();
upsert contactsToUpsert;

Senior Architect Best Practices & Limits#

• Check FLS / CRUD After output application/apex: Instantiating SObjects inside a .dwl script bypasses UI-level field checks just like new Contact() in Apex. Always run insert as user contactsToUpsert or Security.stripInaccessible() before committing records parsed from external files.

Frequently asked questions

Why should developers use DataWeaveResource in Apex instead of custom CSV or XML parsers?

Parsing large CSV files with escaped commas/newlines or deeply nested XML payloads in native Apex frequently triggers Apex CPU time limits and heap size exceptions. DataWeaveResource offloads data transformation to MuleSoft's compiled DataWeave 2.0 engine.

How do you invoke a DataWeaveResource script from an Apex class?

Salesforce generates a strongly typed class under the DataWeaveScriptResource namespace (such as new DataWeaveScriptResource.csvToContacts()), or you can load it dynamically via DataWeave.Script.createScript('csvToContacts') and call execute(parameters).

Can a DataWeaveResource script output SObject instances directly?

Yes! By setting output application/apex in the .dwl script header and appending as Object {class: 'Account'} (or any custom SObject or Apex class), script.execute() returns a List of SObjects that you can pass directly to Database.insert().

What does the isGlobal field do in a .dwl-meta.xml file?

When isGlobal is set to true in a managed package, the generated DataWeaveScriptResource.ScriptName Apex class is marked global so subscriber org Apex code can instantiate and execute the DataWeave script.