About Mule Configuration

Following is an introduction to configuring Mule via the Spring XML file. For details on this file, see About the XML Configuration File.

Mule Configuration File Overview

A Mule configuration file is a tree, as shown in the following illustration:

Each of these elements provides access to a configuration object within Mule:

Custom Message Processors - Observe a message, or modify either a message or the message flow. Examples include transformers and filters.
Flows - Use message processors to define message flow between a source and a target.
Mule Global Configuration - Global settings, such as the default transaction time-out, that apply to the entire Mule configuration
Connectors - Non-default configuration of any transports used
Endpoints - Define the channel and address or path where messages are sent or received. You can define them globally and use them in multiple flows.
Transformers - Convert data from one format to another. You can define them globally and use them in multiple flows.
Filters - Filter out the messages that don’t match specific criteria. You can define them globally and use them in multiple flows.

Following is an example of a simple Mule configuration file:

Simple Mule Configuration

<mule xmlns="http://www.mulesoft.org/schema/mule/core"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:vm="http://www.mulesoft.org/schema/mule/vm"
      xsi:schemaLocation="
          http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
          http://www.mulesoft.org/schema/mule/vm http://www.mulesoft.org/schema/mule/vm/current/mule-vm.xsd">

    <vm:connector name="vmConnector" queueTimeout="5000"/>

    <vm:endpoint name="CustomerRequests" path="customer.requests"/>
    <vm:endpoint name="CustomerResponses" path="customer.responses"/>

    <custom-transformer name="ThisToThat" class="com.acme.transformer.ThisToThat"/>

    <flow name="myBasicFlow">
        <inbound-endpoint ref="CustomerRequests"/>
        <component class="com.acme.service.BasicService"/>
        <outbound-endpoint ref="CustomerResponses" transformer-refs="ThisToThat"/>
    </flow>
</mule>

Other, more advanced things you may configure at this level:

Security Manager - Authenticates requests based on one or more security providers
Agents - Agents are typically used for cross-cutting concerns such as logging or management
Notifications - Allow you to be notified upon certain lifecycle events
Transaction Management - Mule transactions are configured on inbound endpoints, where an endpoint can be configured to start a new transaction or join an existing one.
Properties - Property placeholders, message properties, and system properties.

Global Configuration Settings

You can configure global configuration settings such as the default transaction timeout and default threading profile in the <configuration> element. For example:

<mule>
...
  <configuration defaultTransactionTimeout="31337">
    <default-threading-profile poolExhaustedAction="RUN"/>
...
  </configuration>

For a list of the available global configuration settings, see Global Settings Configuration Reference.

Accessing the Configuration Programmatically

All Mule configuration is accessible from a single object: org.mule.api.config.MuleConfiguration.

Configurations in a MuleConfiguration are set when a MuleContext is created. The object becomes immutable after it is started and can be accessed using the following:

// implement MuleContextAware to have the reference injected
MuleConfiguration configuration = context.getConfiguration();