Mule Runtime Engine 4.4.0 Release Notes

Mule runtime engine (Mule) is a lightweight integration engine that runs Mule applications and supports domains and policies.

October 5, 2021

What’s New

Mule 4.4.0 includes important enhancements and fixes.

Enhancements

  • Correlation ID Management

    Mule 4.4 enables you to modify the correlation ID associated with a Mule event. You can also change the algorithm Mule uses to generate each correlation ID.

    See Correlation ID for additional information and configuration instructions.

  • Improved Logging Capabilities

    Mule 4.4 incorporates the Mule Tracing module, which you can use to add, remove, and clear variables from the logging context for a given Mule event.

    See MDC Logging for additional information and configuration instructions.

  • Feature Flagging Mechanism

    Mule 4.4 incorporates a feature flagging mechanism, which enables you to disable certain features that change core functionality in Mule to avoid backward compatibility issues.

    The following are the feature flags introduced in this release and its corresponding fixed issue ID:

    Feature Flag Issue ID

    HONOUR_RESERVED_PROPERTIES_PROPERTY

    MULE-17659

    HANDLE_SPLITTER_EXCEPTION_PROPERTY

    DW-383

    BATCH_FIXED_AGGREGATOR_TRANSACTION_RECORD_BUFFER_PROPERTY

    MULE-19218

    COMPUTE_CONNECTION_ERRORS_IN_STATS_PROPERTY

    MULE-19020

    TO_STRING_TRANSFORMER_TRANSFORM_ITERATOR_ELEMENTS_PROPERTY

    MULE-19323

    ENABLE_POLICY_ISOLATION_PROPERTY

    MULE-19226

    ENTITY_RESOLVER_FAIL_ON_FIRST_ERROR_PROPERTY

    EE-7827

    ENABLE_PROFILING_SERVICE_PROPERTY

    MULE-19588

    SET_VARIABLE_WITH_NULL_VALUE_PROPERTY

    MULE-19443

    See Feature Flagging for a detailed description of each feature flag and configuration instructions.

Bundled Components

  • Runtime Manager Agent plugin version 2.4.21

  • Dataweave version 2.4.0

Fixed Issues

Mule Runtime Issue ID

The tooling service in Anypoint Studio now properly propagates metadata for DataWeave Intersection types.

SE-22333

Mule runtime engine uses the correct version of the disruptor.

SE-19387

Fixed a metaspace memory leak in Anypoint Connector for Database (Database Connector).

SE-15818

HTTP requests with OAuth now use a valid token.

SE-15667

Console logs do not produce repeated log messages for the completion of a single batch job.

SE-11533

Fixed the Illegal reflective access warnings for OpenJDK 11.

SE-13349

After a connection is re-established, SFTP files are now picked up properly.

MULE-18294/SE-13897

In Azure Service Bus Connector, when a flow is stopped, the message listener now stops polling.

SE-17389

API Manager now properly handles connection pool exhaustion and no longer shows APIs in INACTIVE state.

SE-15351

Anypoint Connector for NetSuite (NetSuite Connector) no longer makes excessive getServerTime calls.

SE-15200

An application no longer fails to deploy if it uses the same custom name space as an applied custom policy.

SE-15056

Applications using Anypoint Connector for Database (Database Connector) under heavy load no longer show StackOverflow errors.

SE-14663

Mule no longer produces an exception related to class loading when the class exists as a dependency and is configured as a shared library.

SE-14245

When an encoded slash is sent as the value of a URI parameter, the associated listener is now found.

SE-14046

Mule 4 no longer fails to stream the complete payload to the client.

SE-14012

The ErrorType no longer changes when entering an Error Handler scope.

SE-13673

Proxies no longer experience outages during redeployment in Anypoint Runtime Fabric configured with two replicas and rolling update.

SE-13596

DataWeave Issue ID

Added the writeDeclaredNamespaces XML writer property to write all declared namespaces in the root element.

DW-16

Added the writeDeclaration YAML writer property to avoid writing the header declaration.

DW-162

Added a new Strings module for easier string data management.

DW-406

Added the constant folding functionality so that DataWeave replaces operations involving constant values with the actual result. For example, 1024*8 is replaced at compile time with the resulting value 8192.

DW-427

Added flow retyping to the type system, which enables better accuracy within flow-control structures featuring checks that involve typing.

DW-438

Added code inspectors so that quick fixes are suggested with best practices, such as replacing null checks with a default expression, or replacing sizeOf() == 0 with isEmpty().

DW-33/DW-632

Added an inspection to replace using with do blocks.

DW-771

Improved error messages when creating Java objects.

DW-565

Improved performance on floating point number parsing by identifying in advance if the number has a floating point or not.

SE-20614

Extended the common subexpression elimination process to work with index selectors.

SE-19934

Added functions that work with null values to the Core, Arrays, and String modules.

DW-425

Improved JSON performance by copying bytes from input to output directly during JSON-to-JSON data transformations.

DW-230

Improved YAML support of scalar types, string quotations, custom tags, and comment retention.

DW-687

Added the filterTree function to the Tree module to be able to filter any data structure.

DW-160

Added validations for index tokens in CSV format.

DW-577

Added support for the Java classes OptionalInt, OptionalDouble and OptionalLong.

DW-628

Added support for file:/example/file.txt as a valid URL.

DW-195

Added warning when using the design-time only format application/dw without dataOnly mode.

DW-873

Added experimental run and eval functions to dynamically execute scripts.

DW-170

Added the concept of optional function parameters in the type system.

DW-874

Improved CSV streaming to avoid unnecessary processing.

DW-876

Improved the mapObject function to avoid unnecessary processing.

DW-535

Improved the flatten function to avoid unnecessary processing.

DW-509

Improved code validation. Now an error returns when a variable is using the same name as an input.

DW-522

Improved the precision of math operations and added a property to retain the previous behavior: com.mulesoft.dw.math.exact_precision.

SE-16452

Improved handling of big XML files to fix potential I/O exceptions.

DW-250

Fixed error locations when scripts feature dynamic string selectors.

DW-875

Fixed a false negative error message when using multiple union types.

DW-297

The write function return types are now consistent with input types.

DW-298

The update operator no longer fails when working with repeated keys and attributes.

DW-306

Processing of XML documents with comments and streaming enabled now works as expected.

DW-307

DataWeave no longer fails to parse a single key-value pair with a conditional and parentheses.

DW-309

The type system now validates overloaded functions as parameters.

DW-316

Parallel processing on ndjson now works as expected.

DW-325

Fixed a materialization and streaming failure.

DW-368

Fixed the behavior of the slice function.

DW-409/DW-410

Fixed the ability to import namespaces from external modules.

DW-414

DataWeave now produces the error Division by Zero when dividing by 0.0 instead of an internal exception.

DW-415

DataWeave now properly validates that do blocks do not contain any reserved word declaration.

DW-416

Running flatten on flatten no longer causes loss of values.

DW-691

The update operator now works when no attribute is defined.

DW-216

Improved handling of binary data to prevent running out of memory when calculating sizes of processed data.

SE-16559

The com.mulesoft.dw.coercionexception.verbose property no longer logs data from coercion exceptions.

SE-15487

Using nested binary functions no longer produces a StackOverflow error.

SE-16092

DataWeave no longer returns UnsupportedOperationException when parsing an invalid script.

DW-294

Fixed a potential IndexOutOfBoundException when using overloaded functions with four parameters.

DW-159

Added support for dumping Flat File and Avro schemas when com.mulesoft.dw.dump_files is enabled.

DW-137

Known Issues

Issue ID

Mule AS2 Connector 5.x is not compatible with Mule 4.4. For any applications that use this version of the connector, upgrade the connector to the latest version available in Exchange.

EE-8071

WSDL Proxies on version 1.1.1 and 1.1.2 are not compatible with Mule 4.4. Before you upgrade to 4.4, upgrade the WSDL Proxies to a newer version.

EE-8070

Mule SAP Connector 5.3.4 is not compatible with Mule 4.4. For any applications that use this version of the connector, upgrade the connector to the latest version available in Exchange.

EE-8061

Upgrade

If you are upgrading to Mule 4.4 from an earlier Mule 4.x version, see Upgrading Mule Runtime Engine (Versions 4.x to 4.n) for upgrade instructions.

To ensure optimal performance with Mule 4.4 and avoid unexpected issues, update the following modules and extensions to their latest version at the time of this release:

Module or Extension Version

APIkit for Mule 4

1.5.5

APIkit for SOAP

1.2.9

Spring module

1.3.6

MUnit plugin

2.3.6

Module Testing Framework (mtf-tools)

1.1.1

Considerations for Mule Extensions Developers

If you update the version of your parent pom.xml file to 1.4.0 or later when you build a Mule extension, ensure that the dependencies in your pom.xml file do not override dependencies defined in the parent pom.xml file and declare only the dependencies you need. If you need to declare a dependency that is already declared in the parent pom.xml file, do not specify a version so it uses the version from the parent pom.xml file.

Was this article helpful?

💙 Thanks for your feedback!