Sample Five: RESTDataSource

' SBM ModScript Example: RESTDataSource.tscm

/*  ModScript Example: RESTDataSource.tscm
    -----------------------------------
    Use a RESTDataSource object. These can be created in Composer and bound to a URL, 
    or bound to an endpoint that can have a different URL per runtime environment.

    Requirement: Deploy a RESTDataSource named "JSONPlaceHolder1" pointing to the 
    "https://jsonplaceholder.typicode.com/users" service.

    Logic: Read a row from TS_RESTDATASOURCE, , invoke it via Get, parse the JSON into 
    an object, process the object */

var restSource = Ext.CreateAppRecord(Ext.TableId("TS_RESTDATASOURCE")); 
//This is a REST Data Source
restSource.Read("JSONPlaceHolder1");

var result = "";
try {
	restSource.Get(result);
} catch(e) {}

var resultObj = from_json(result);

//Ext.WriteStream(result &&& "</br>"); 
// writing the JSON out might help you understand what you are parsing

/* Sometimes, you can get lost in your JSON object; do I have a map, a vector, 
or perhaps a string or integer? Printing out the data type of what "from_json" 
created might guide you in the code to write to process that 
object: Ext.WriteStream( resultObj.get_type_info().name() );
*/

Ext.WriteStream( "<dl>" );
for(entry : resultObj) {
  Ext.WriteStream( "<dt>${entry["username"]}</dt>"); 
  // ChaiScript supports in-string script processing. 
  →Here, we evaluate "entry["username"]", which looks in the map for the 
		→username value and returns it
  for(value : entry) {
      Ext.WriteStream("<dd>${value.first()}: ");
      if(value.second().is_type(Map_type)) { 
	  // we can check if we got a map object using this call. 
			→Another version that does the same thing: 
   →value.second().get_type_info().name() == "Map"
          Ext.WriteStream("<dl>");
          for(inner : value.second()) {
              if(inner.second().is_type(Map_type)) { 
              // OK, we could process this map, too, but you get the idea
                 continue;
              }
              Ext.WriteStream("<dd>${inner.first()}: ${inner.second()}</dd>");
          }
          Ext.WriteStream("</dl>");
      } else {
          Ext.WriteStream(value.second());
      }
      Ext.WriteStream("</dd>");
  }
} 
Ext.WriteStream( "</dl>" );