Creating JSON request for REST web services

PeopleSoft provides Document technology to be used to generate JSON request messages but in my experience they are very restrictive especially when working on integrating with 3rd party web services. So following is what I did to generate a JSON request message to post to a 3rd party REST web service. 

The request that I have to generate is in the following form.
[
   {
      "attrib1":"value1",
      "attrib2":"value2",
      "attrib3":{
         "attrib3_1":"values3_1",
         "attrib3_2":"values3_2",
         "attrib3_3":"values3_3",
         "attrib3_4":"values3_4"
      }
   }
]

I am running PT 8.57.x and at this time its not possible to build a document with the root node as an array as shown in the example below. Also I have nested compounds which is also a challenge, the parent compound does not have a label where as the child does. 
So to build something like above I am using the CreateJsonBuilder API provided by PeopleSoft.

Local JsonBuilder &jbldr = CreateJsonBuilder();
Local JsonArray &jArray;

Local string &json;
Local message &request, &response;
Local boolean &bRet;

&jbldr.StartArray(""); /* no label */
 &jbldr.StartObject(""); /* no label */
  &jbldr.AddProperty("attrib1", "value1");
  &jbldr.AddProperty("attrib2", "value2");
   &jbldr.StartObject("attrib3"); /* need a label */
    &jbldr.AddProperty("attrib3_1", "value3_1");
    &jbldr.AddProperty("attrib3_2", "value3_2");
    &jbldr.AddProperty("attrib3_3", "value3_3");
    &jbldr.AddProperty("attrib3_4", "value3_4");
   &jbldr.EndObject("attrib3"); /* closing out the compound or JSONObject */
 &jbldr.EndObject("");
&jbldr.EndArray("");


/* this will return the array just like what I want */
&jArray = &jbldr.GetRootNode().GetJsonObject().GetJsonArray("");
&json = &jArray.ToString();

Created a basic non-rowset based message and assigned that as the request message in my service operation. Use this method to set the content for the message segment for a non-rowset-based message only.

&bRet = &request.SetContentString(&json);
&response = %IntBroker.SyncRequest(&request);

That's it, works like a charm.

PeopleSoft RESTful Webservice

Here is my initial exposure to creating a RESTful webservice in PeopleSoft. I am running HR 9.1 on PT 8.53.x. 
The requirement is to provide a list of locations based on a region input and then provide a list of employees in that region/location combination.
Here is the flow.

This is accomplished by creating a provider service using the GET method.
I am assuming the basic IB setup is in place, which is essentially making sure the local gateway is up and running and under Service configuration, the REST target location is provided. 

Navigate to PeopleTools > Documents > Document Builder.
First create a document with 2 primitives called as "REGION" and  "LOCATION".
We could have just created a non-rowset based message, but document object provides the flexibility to exchange data in XML or JSON format whereas non-rowset based message would be just XML.
Both primitives will be of the type string, sub-type = None. Adjust the length appropriately, in my case region is just a 1 char code and location is 10 chars.

Now create a response document. This document will have 2 collections one for the location data and the other for the employee data. Under each collection I added a compound child which is essentially a view (record) that I created which will return the appropriate data elements. 
LOC_RESPONSE  -- root element
      LOC_DATA -- collection
            LOC_DTL_VW -- compound
      EMP_DATA -- collection 
            EE_LIST_VW -- compound 

When the compound child is created behind the scenes PeopleSoft creates another document. So make sure the naming of each type is appropriate otherwise it can get pretty confusing. 

Now I created another document which I am going to use for handling fault, this has only one primitive in it of the type text.

After each document is created and saved, verify the document using the "Validate" and "Document Tester" options available on the page.

From the document now create messages, so navigate to PeopleTools > Integration Broker > Integration Setup > Messages. Add new messages of type document. You can keep the document name and message name same. Did this for all the three documents that I created in the earlier step. Once in just click save. The page looks similar to the document builder page, with the addition of the metadata reference section visible at the top of the page. No additional work is required here.

Now navigate to PeopleTools > Integration Broker > Integration Setup > Services and create a REST service. Make sure the "REST Service Type" check-box and the "Is Provider" check-box is checked. Save the service. 
Now select the REST method, in my case "Get", provide a service operation name and click on Add. The REST method is appended to the service operation name.

the REST Base URL will be grayed out and would be auto-populated with the setup info and service name. Under the URI section I have the following indexes.

1. Locations/?region={REGION}
2. Locations/{REGION}/?location={LOCATION}

Document Template - lookup the request document that was created in the first step above. This is the document which has the 2 primitives defined. The primitive name should match what is provided in the curly brackets under the URI section. 

Make the service operation active. Generate any-to-local routing.
Associate the response and fault messages appropriately. In my case the data exchange would be done in JSON format, so under content type I selected "application/json".

Provide service operation security. Verify routing info. Enable logging if required. Doesn't help much in case of JSON messages though.

For the handler section we need to write application package peoplecode for the OnRequest method.  
Following is the basic structure.

import PS_PT:Integration:IRequestHandler;

class Locations implements PS_PT:Integration:IRequestHandler

   method Locations();

   method OnRequest(&MSG As Message) Returns Message;

   method OnError(&request As Message) Returns string;

end-class;

/* constructor */

method Locations

end-method;

method OnRequest

   /+ &MSG as Message +/

   /+ Returns Message +/

   /+ Extends/implements PS_PT:Integration:IRequestHandler.OnRequest +/

   /* Variable Declaration */

  

End-method;

method OnError

   /+ &request as Message +/

   /+ Returns String +/

   /+ Extends/implements PS_PT:Integration:IRequestHandler.OnError +/

End-method;

Once the service operation is saved, a WADL has to be generated. So navigate back to services and click on the "Provide Web Service" link and step through the wizard.

Once this is done you can test it from an utility like SOAPUI (yes can be used to test RESTful web services) or plain browser or via PeopleTools > Integration Broker > Services Utilities > Provider REST Template.

So the call to this service would be like so.
http://servername/PSIGW/RESTListeningConnector/Locations.v1/Locations/?region=A
which will return all locations in region A and,


http://servername/PSIGW/RESTListeningConnector/Locations.v1/Locations/A/?location=XYZ01
which will return employees in region A and Location XYZ01. Location XYZ01 is returned by the first call.

Output 1:

<?xml version="1.0"?> 
<data psnonxml="Yes"> 
  <![CDATA[
{"LOC_RESPONSE": {
"LOC_DATA": [
{
"ADDRESS1": "1 Palace Dr",
"CITY": "",
"DESCR": "My Location",
"DESCRSHORT": "My Location",
"EFFDT": "2010-08-02",
"EFF_STATUS": "A",
"EXTENSION": "",
"FAX": "",
"LOCATION": "XYZ01",
"MESSAGE_TEXT2": "",
"PHONE": "",
"POSTAL": "",
"STATE": ""
},
{
"ADDRESS1": "100 Main Street",
"CITY": "",
"DESCR": "New Location",
"DESCRSHORT": "New Location",
"EFFDT": "2011-08-02",
"EFF_STATUS": "A",
"EXTENSION": "",
"FAX": "",
"LOCATION": "ABC01",
"MESSAGE_TEXT2": "",
"PHONE": "",
"POSTAL": "",
"STATE": ""
}
],"EMP_DATA": {"DEPTNAME": "","EMAIL_ADDR": "","NAME": "","PHONE": "","TITLE": ""}}
} ]]> 
</data>

Output 2:

<?xml version="1.0"?> 
<data psnonxml="Yes"> 
  <![CDATA[{"LOC_RESPONSE": {
"EMP_DATA": [
{
    "DEPTNAME": "My Location Dept",
"EMAIL_ADDR": "jon.doe@company.com",
"NAME": "Doe,Jon",
"PHONE": "123456789",
"TITLE": "Managing Director"
},
{
    "DEPTNAME": "My Location Dept",
"EMAIL_ADDR": "jane.doe@company.com",
"NAME": "Doe,Jane",
"PHONE": "123456789",
"TITLE": "Managing Director"
}
]}
} ]]> 

</data>