WSO2 EI JSONBuilder 配置

Question

I have this xml which needed to be processed and converted to JSON:

<jsonObject>
    <number>1234</number>
    <emptyString/>
    <string>hello</string>
</jsonObject>

When it runs through JsonStreamBuilder like this:

<property name="messageType" scope="axis2" type="STRING" value="application/json"/>

I get JSON like that:

{
  "number":1234,
  "emptyString": null,
  "string":"hello"
}

So I am wondering is there any way that I can configure JsonStreamBuilder to treat empty tag not as null, but as empty string, furthermore I want numbers to be treated as strings as well.

Maybe I can modify the default XML to fit my needs?

BTW I am using WSO2 EI 6.1.1

Answer 1

The default behavior of JsonFormatter is to allow primitive types in the JSON output. This means any content that is a valid number will be represented in the JSON message as a number.

As a solution for this issue, you could disable, the conversion to primitive type after adding below property to the synapse.properties file of EI_HOME/conf directory.

synapse.commons.json.output.autoPrimitive=false 

However, this property is a global property, so it will be effected to all the services (Proxy services and the APIs). So this means any string that is a valid number will not be converted to a number.

According to your issue, you need to disable the conversion of String to Integer. You could solve this, adding below properties into EI_HOME/conf/synapse.properties file also.

synapse.commons.json.output.autoPrimitive=true

synapse.commons.json.output.disableAutoPrimitive.regex=^[1-9]*$

In this case, auto primitive disables for the numbers only.

NOTE : Once autoprimitive is enabled, some fields can be excluded from the auto primitive functionality based on the regular expression defined in the synapse.properties file.

• And the empty tag as the not null issue, you can resolve following the above-mentioned blog post.

Answer 2

This looks like restriction in wso itlsef, documentation states that is desired behavior. To overcome issue have try script mediator WSO2ESB: Property setting not accepting empty value or getting even lower (more complicated) https://medium.com/@lashan/class-mediator-to-handle-null-values-in-json-payload-wso2-ei-34a43246f0f

Answer 3

If you were using a more recent WSO version, there is a solution: https://docs.wso2.com/display/EI630/Working+with+Message+Payloads#WorkingwithMessagePayloads-EmptyXMLelementswiththe'nil'attribute

You can set synapse configs locally with the help of JSON Transform mediator