Json Enrich Mediator

This mediator works with native JSON in WSO2 ESB. Existing mediator does not support JSON manipulations.

Configuring Mediator

Build this repository with maven

Add following .jar files to ESB_HOME/repository/components/dropins

• JsonEnrichMediator-1.0.0.jar
• json-path-2.1.0.jar (external)
• json-smart-2.2.jar (external)

Syntax

<enrich>
    <source [clone=true|false] [type=custom|payload|property|inline] JSONPath="" property="" key="" />
    <target [type=custom|payload|property] [action=set|add|put] JSONPath="" property="" />
</enrich>

The main properties of JsonEnrichMediator are;

• Source
• Target

Source Configurations

The following properties are available:

• clone - By setting the clone configuration, the source value can be cloned or used as a reference during enriching. The default value is false.

  • true
  • false

• type - The type that the mediator uses from the original message to enrich the modified message that passes through the mediator.

  • custom - Custom JSONPath value. JSONPath attribute must specify the JSONPath expression.
  • payload - Complete original message uses for enriching.
  • property - A property in synapse-message-context uses for enriching. property attribute must specify the property name.
  • inline - Specify and inline JSON object or use key attribute a value specified as a local-entry.

• JSONPath - JSONPath expression uses to select the source, if the type is custom. The value should comply with syntax given at here

• property - Name of the property in synapse-message-context that should be used for enriching, if the type is property.

• key - Key value of the inline JSON that should be used for enriching, if the JSON is specified as a local-entry.

Target Configurations

The following properties are available:

• type - The type that the mediator uses from the original message to enrich the modified message that passes through the mediator.

  • custom - Custom JSONPath value. action attribute must specify the action to be used. JSONPath attribute must specify the JSONPath expression.
  • payload - Complete original message needs to replace.
  • property - A new property in synapse-message-context uses as the target. property attribute must specify the property name.

• action - By specifying the action type, the relevant action can be applied to outgoing messages.

  • set - Replaces the value of the property in JSONPath with the source value
  • add - Adds the source value to the JSON array specified by JSONPath.
  • put - Adds a new property to the JSON object specified by JSONPath. property attribute must specify the new property name.

• JSONPath - JSONPath expression uses to select the source, if the type is custom. The value should comply with syntax given at here

• property - Name of the new property should be added, if the type is property or custom (when the action is put).

Examples

Following JSON payload is used as the input

{
	"me": {
		"country": "Sri Lanka",
		"language" : "Sinhala"
	}
}

Example 1: Extracting a value from payload

Extracting a value specified by JSONPath to a synapse-context-property

<jsonEnrich>
    <source type="custom" clone="true" JSONPath="$.me.country"/>
    <target type="property" property="newPlace"/>
</jsonEnrich>

Example 2: Move a value in payload

Cut and paste a value in payload to a new location

<jsonEnrich>
    <source type="custom" clone="false" JSONPath="$.me.country"/>
    <target type="custom" action="put" JSONPath="$" property="country"/>
</jsonEnrich>

Output

{
  "me": {
    "language": "Sinhala"
  },
  "country": "Sri Lanka"
}

Example 3: Replace a property with inline JSON

<jsonEnrich>
    <source type="inline">
        {"name" : "Buddhima"}
    </source>
    <target type="custom" action="set" JSONPath="$.me"/>
</jsonEnrich>

Output

{
  "me": {
    "name": "Buddhima"
  }
}

Future Improvements

• Add "action" support when target type is "property"

If you have suggestions or issues, please mention them at "issues" section at GitHub repository.