OSB-12c : JSON Message Type

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It is easy for humans to read and write.

We can use RESTful services in order to read JSON files.

In below example a sample REST service is created in OSB-12c and this service takes input and return response in JSON format.

·         Create REST adapter to take input.

Create sample HTTP based REST service and add some logic in it.

Create new folder inside MessageType_Service

File -> New -> Folder -> JSON_MessageTypeServices

Create sub folders as mentioned below

Create few more extra folders like WSDL,WADL,XSDs inside Resources

Create a REST based adapter in design view

Design View (right click on Proxy Service Module) -> REST

Specify proper name for REST binding

Add a method. Let Method name be as ‘ExecuteRest’.

Click on radio button of ‘JSON’ and ‘XML’.

This indicates that input to REST adapter can be in format of JSON or XML.

Specify HTTP verb as GET and Response as JSON

HTTP Verb: GET

Response Type: JSON

Cross check whether all configurations are done and click on ‘Finish’ button.

Method: ExecuteRest

Resource Path: /

HTTP Verb: GET

Complete: yes

Once REST adapter configuration is done, we can see error in SampleRestProxy(This proxy will get created during configuration of REST adapter).

This is expected as we have not targeted any of other resources like BusinessService or ProxyServices to this proxy.

Create new pipeline with help of WADL which is got created while creation of REST adapter and add some logic to it.

Service Name: RestServicePipeline

Service Type: REST

Uncheck radio button for ‘Expose as proxy service’.

Select the WADL ‘SampleRestService.wadl’ which is got created while creation of REST adapter.

Add pipeline pair and request and response stages in ‘RestServicePipeline.pipeline’

Add a assign activity and include some logic into it.

In this example value of user-metadata from $inbound is concatenated with string ‘Value of ID:’

concat (‘Value of ID :’ ,$inbound/ctx:transport/ctx:request/tp:user-metadata/@value)

And assign this to a variable called ‘AssignedRequest’.

Create new nXSD schema which is used to convert XML to JSON.

Resources -> XSDs (Right Click) -> New -> nXSD schema

A pop-up window of Native Format builder will open

Specify proper name for nXSD schema

Name: XMLtoJSON.xsd

Choose type as ‘JSON Interchange Format’

Specify sample structure of JSON

{

“Response” : “Value of ID =”

}

When we click on next we can see xsd structure for JSON.

Click on Finish button to complete Native Builder format activity.

You can locate XMLtoJSON.xsd got created inside ‘XSDs’ folder.

Add a nXSD translate activity to convert XML to native (JSON) format.

Right Click in response pipeline -> Insert Into -> nXSD translate

Specify below values in nXSD translate activity

Translate: XML to native

Input: Add some logic like mentioned below

<Root-Element xmlns="http://TargetNamespace.com/ServiceName">

 <Response>{$AssignedRequest}</Response>

</Root-Element>

nXSD schema: Select XMLtoJSON.xsd schema (nXSD schema)

Output: contents of body

Deploy the service into local standalone weblogic server.

We can see deployed services in sbconsole

Run RestService

Pass value of ID

Accept: application/json

ID : <Some value>

Hit Execute button.

We can see that response is in JSON format.