Combining multiple JSON arrays using WSO2 aggregator - wso2

Question

I'm trying to combine two different data sources into a single data feed using WSO2 ESB. Because the different sources have different data formats my approach has been to create a proxy for each endpoint to deal with authorisation and payload formatting so that both return a JSON array. Based on research my assumption was that I could then to use the aggregator mediaor to combine the results. After working through lots of examples I have combined the two arrays successfully however one of the arrays is always duplicated. Can anyone see what I am doing wrong or does anyone have any other suggestions about a better way of achieving the combination of two JSON arrays?
I have set up the following code examples to simulate 2 feeds and then combine with my code:
<?xml version="1.0" encoding="UTF-8"?>
<proxy name="testb_url1" startOnLoad="true" trace="disable"
transports="https http" xmlns="http://ws.apache.org/ns/synapse">
<target>
<inSequence>
<payloadFactory media-type="json">
<format>[
{"id": "1",
"type": "object",
"name": "first"},
{"id": "2",
"type": "object",
"name": "second"}
]
</format>
<args/>
</payloadFactory>
<log level="full"/>
<loopback/>
</inSequence>
<outSequence>
<send/>
</outSequence>
<faultSequence/>
</target>
</proxy>
URL number 2
<?xml version="1.0" encoding="UTF-8"?>
<proxy name="testb_url2" startOnLoad="true" trace="disable"
transports="https http" xmlns="http://ws.apache.org/ns/synapse">
<target>
<inSequence>
<payloadFactory media-type="json">
<format>[
{"id": "10",
"type": "object",
"name": "ten"},
{"id": "11",
"type": "object",
"name": "eleven"}
]
</format>
<args/>
</payloadFactory>
<log level="full"/>
<loopback/>
</inSequence>
<outSequence>
<send/>
</outSequence>
<faultSequence/>
</target>
</proxy>
Code to combine:
<?xml version="1.0" encoding="UTF-8"?>
<proxy name="testb_combine" startOnLoad="true" trace="disable"
transports="https http" xmlns="http://ws.apache.org/ns/synapse">
<target>
<inSequence>
<property name="enclosing_element" scope="default">
<jsonArray xmlns=""/>
</property>
<send>
<endpoint>
<recipientlist>
<endpoint>
<address uri="http://localhost:8280/services/testb_url1/" trace="disable"/>
</endpoint>
<endpoint>
<address uri="http://localhost:8280/services/testb_url2/" trace="disable"/>
</endpoint>
</recipientlist>
</endpoint>
</send>
</inSequence>
<outSequence>
<enrich>
<source clone="true" xpath="$body/jsonArray/jsonElement"/>
<target action="child" xpath="$ctx:enclosing_element"/>
</enrich>
<aggregate>
<completeCondition>
<messageCount min="-1" max="-1"/>
</completeCondition>
<onComplete expression="$body/jsonArray/jsonElement"
enclosingElementProperty="enclosing_element">
<send/>
</onComplete>
</aggregate>
</outSequence>
<faultSequence/>
</target>
</proxy>
And returned results showing data from URL 1 duplicated:
[
{
"id": 1,
"type": "object",
"name": "first"
},
{
"id": 2,
"type": "object",
"name": "second"
},
{
"id": 1,
"type": "object",
"name": "first"
},
{
"id": 2,
"type": "object",
"name": "second"
},
{
"id": 10,
"type": "object",
"name": "ten"
},
{
"id": 11,
"type": "object",
"name": "eleven"
}
]

Answer 1

Remove the enrich mediator in the outsequence and it work like you want:
Proxy service:
<?xml version="1.0" encoding="UTF-8"?>
<proxy xmlns="http://ws.apache.org/ns/synapse"
name="testb_combine"
transports="https http"
startOnLoad="true">
<target>
<inSequence>
<property name="enclosing_element" scope="default">
<jsonArray xmlns=""/>
</property>
<send>
<endpoint>
<recipientlist>
<endpoint>
<address uri="http://localhost:8283/services/testb_url1/"/>
</endpoint>
<endpoint>
<address uri="http://localhost:8283/services/testb_url2/"/>
</endpoint>
</recipientlist>
</endpoint>
</send>
</inSequence>
<outSequence>
<aggregate>
<completeCondition>
<messageCount min="-1" max="-1"/>
</completeCondition>
<onComplete expression="$body/jsonArray/jsonElement"
enclosingElementProperty="enclosing_element">
<send/>
</onComplete>
</aggregate>
</outSequence>
<faultSequence/>
</target>
</proxy>
Response:
[
{
"id": 1,
"type": "object",
"name": "first"
},
{
"id": 2,
"type": "object",
"name": "second"
},
{
"id": 10,
"type": "object",
"name": "ten"
},
{
"id": 11,
"type": "object",
"name": "eleven"
}
]