Scopes

In WSO2 Micro Integrator scopes refer to the different layers where the properties can be set when mediating messages.

default scope

When the scope of a property is default, its value is available throughout the mediation flow. In addition to the user-defined properties, you can retrieve the following special properties from the default scope. Generic Properties are available in the default scope.

Property name	Return value
To	Incoming URL as a string, or empty string («») if a To address is not defined.
From	From address as a string, or empty string («») if a From address is not defined.
Action	SOAP Addressing Action header value as a string, or empty string («») if an Action is not defined.
FaultTo	SOAP FaultTo header value as a string, or empty string («») if a FaultTo address is not defined.
ReplyTo	ReplyTo header value as a string, or empty string («») if a ReplyTo address is not defined.
MessageID	A unique identifier (UUID) for the message as a string, or empty string («») if a MessageID is not defined. This ID is guaranteed to be unique.
FAULT	TRUE if the message has a fault, or empty string if the message does not have a fault.
MESSAGE_FORMAT	Returns pox, get, soap11, or soap12 depending on the message. If a message type is unknown this returns soap12
OperationName	Operation name corresponding to the message. A proxy service with a WSDL can have different operations. If the WSDL is not defined, WSO2 MI defines a fixed operation called mediate.

Examples:

<property name="PROPERTY_1" value="VALUE_1" scope="default" type="STRING"/>
<property name="PROPERTY_2" expression="get-property('PROPERTY_1')"/>

Note

To access a property with the default scope inside the mediate() method of a mediator, you can include the following configuration in a custom mediator created using the Class mediator:

public boolean mediate(org.apache.synapse.MessageContext mc) {  
    // Available throughout the mediation flow  
    String propValue = (String) mc.getProperty("PropName");  
    System.out.println("SCOPE_SYNAPSE : " + propValue);  
    return true;  
}

axis2 scope

When the scope of a property is axis2, its value is available only either throughout the request flow or the response flow for which the property is defined. Axis2 Properties are available in the axis2 scope.

You can retrieve message context properties within the axis2 scope using the following syntax.

get-property('axis2', String propertyName)

Examples:

<property name="PROPERTY_1" value="VALUE_1" scope="axis2" type="STRING"/>
<property name="PROPERTY_2" expression="get-property('axis2',PROPERTY_1')"/>

Note

To access a property with the axis2 scope inside the mediate() method of a mediator, you can include the following configuration in a custom mediator created using the Class mediator:

public boolean mediate(org.apache.synapse.MessageContext mc) {  
    org.apache.axis2.context.MessageContext axis2MsgContext;  
    axis2MsgContext = ((Axis2MessageContext) mc).getAxis2MessageContext();   
    // Available only in the sequence in which the property is defined.  
    String propValue = (String) axis2MsgContext.getProperty("PropName");  
    System.out.println("SCOPE_AXIS2 : " + propValue);  
    return true;  
} 

transport scope

When the scope of a property is transport, it refers to the transport headers of the message. HTTP Transport Properties are available in the axis2 scope.

You can retrieve properties within the transport scope using the following syntax.

get-property('transport', String propertyName)

Examples:

<property name="PROPERTY_1" value="VALUE_1" scope="transport" type="STRING"/>
<property name="PROPERTY_2" expression="get-property('transport',PROPERTY_1')"/>

registry scope

The registry in WSO2 MI allows users to store and manage various resources, such as configuration files, XML schemas, WSDL files, XSLT stylesheets, and other reusable assets. When the scope of a property is registry, it refers to a registry resource or a registry resource property.

You can retrieve properties within the registry using the following syntax.

get-property('registry', String registryPath@propertyName)
get-property('registry', String registryPath)

Examples:

<property name="regProperty" expression="get-property('registry', 'gov:/data/xml/collectionx')"/>
<property name="regResourceProperty" expression="get-property('registry', 'gov:/data/xml/collectionx@abc')"/>

system scope

When the scope of a property is system, it refers to Java System properties. You can retrieve properties in the system scope using the following syntax.

get-property('system', String propertyName)

environment scope

You can retrieve environment variables using the following syntax.

get-property('env', String propertyName)

file scope

You can retrieve properties defined in the file.properties configuration file using the following syntax. Properties in the file are reloaded periodically according to the time interval defined by the file.properties.sync.interval system property in seconds. If this interval is not defined, changes to the properties will not be reloaded automatically during runtime.

get-property('file', String propertyName)

operation scope

You can retrieve a property in the operation context level from the operation scope. The properties within the iterated/cloned message with the operation scope are preserved in the in sequence even if you have configured your API resources to be sent through the fault sequence when faults exist. A given property with the operation scope only exists in a single request and can be accessed by a single resource.

The syntax of the function takes the following format.

get-property('operation', String propertyName)

axis2-client scope

This is similar to the default scope. The difference is that it can be accessed inside the mediate() method of a mediator by including one of the following configurations in a custom mediator, created using the Class mediator:

public boolean mediate(org.apache.synapse.MessageContext mc) {  
    org.apache.axis2.context.MessageContext axis2MsgContext;  
    axis2MsgContext = ((Axis2MessageContext) mc).getAxis2MessageContext();  
    String propValue = (String) axis2MsgContext.getOptions().getProperty("PropName");  
    System.out.println("SCOPE_AXIS2_CLIENT - 1: " + propValue);  
    return true;  
}