Contact Free trial Login

Mule Runtime 4.0 Release Notes

June 26, 2017

Mule 4 beta evolves Mule 3 significantly to enable developers to accomplish common tasks in fewer steps, learn fewer concepts to be successful, simplify upgrades, and support for new web based tools, such as the Flow Designer in Design Center.

This initial release includes:

  • Simplified Event and Message Model.

  • DataWeave 2.0: the new Mule expression language.

  • Simplified Connectors and Modules Experience.

  • Simplified Error Handling and new Try Scope.

  • Transparent streaming of payloads.

  • Ability to enrich Events directly from connectors/modules.

  • Self tuning, non blocking execution engine.

  • Classloader Isolation for Mule runtime, Applications, and connectors.

For a detailed overview of what’s new in Mule 4, please see the What’s New in Mule 4 guide.

DataWeave 2.0 New Features

The DataWeave language entirely replaces everything that Mule Expression Language does, as the default expression language in all Mule components. It has the following improvements over older versions of the language:

  • Importing of external modules with custom and specialized functions.

  • Block comments can be added over multiple lines.

  • Improved error messages with call values and stacktrace.

  • Type checking.

  • Type inference, which makes typing optional.

  • Various syntax changes.

Known Issues

Issue Description


Test connectivity failure causes deployment failure


Live view for flow designer does not work correctly with <try>


No DataSense support for JMS


deleteAfterRetrieve only deletes half of the listed emails


File/FTP read and list should not receive a MediaType as parameter


Db connector bulk-insert operation throws a NPE when bulkInputParameters is null


@Query text does not allow for dynamic values.


Expression language does not suppot accessing system properties


HTTP proxy performance is slow


HTTP Listener source allows config-ref as optional


Scatter-gather router does not handle errors correctly and invokes error handler multiple times


OAuth operations are always executed in a blocking manner


When an app with OAuth Client Credentials doens’t can connect at deployment it doesn’t show the HTTP requester response as in 3.x


NPE when trying to serialize a MultiPartPayload


JMS Publish/consume operation should be non-blocking


When filter throws exception, the handler loses the reference to the filter


ParameterGroup’s order are not populated automatically is a value was not configured manually


HTTP does not support multiple headers/query params (same name)


MuleArtifactClassLoader dispose fail


JAXBMarshallerTransformer fails to transform to byte array


Transformation service must always update message once payload has been consumed


Expression referencing an XML payload fails to resolve


Transform Message - Invalid property 'resource' of bean class

We use cookies to make interactions with our websites and services easy and meaningful, to better understand how they are used and to tailor advertising. You can read more and make your cookie choices here. By continuing to use this site you are giving us your consent to do this.