RTI_RJSON Function

The RTI_RJSON function allows you to evaluate a JSON (JavaScript Object Notation) expression. After passing in a JSON expression, you can invoke the function or evaluate the expression, and retrieve results.

RTI_RJSON uses the open source rapidJSON library.

Please include the RTI_RJSON_EQUATES insert in your stored procedures.

rslt = RTI_RJSON(method [, param1 [, param2 [, param3 [, param4 [, param5]]]]])

The function has the following available methods and parameters:

Example 1:

compile function test_rjson( void )

   $insert rti_rJSON_Equates
   $insert rti_SSP_Equates
   $insert logical
   
   json =  '{'
   json := '"results" : ['
   
   json := '{'
   json := '"business_status" : ' : quote( "OPERATIONAL" ) : ","
   json := '"formatted_address" : ' : quote( "1 Park W Blvd #130, Akron, OH 44320, United States" ) : ","
   json := '"geometry" : ' : quote( "2D" )
   json := '},'
   
   json := '{'
   json := '"business_status" : ' : quote( "DEAD" ) : ","
   json := '"formatted_address" : ' : quote( "11 The Yellow Brick Road, Oz" ) : ","
   json := '"geometry" : ' : quote( "weird" )
   json := '}'
   
   json := ']'
   json := '}'
      
   objDoc = rti_rJSON( RJSON_MTD_PARSE$, json ); goSub checkErr
   if objDoc then
      resultsCount = rti_rJSON( RJSON_MTD_GETITEMCOUNT$, objDoc, "results" ); goSub checkErr
      call rti_rJSON( RJSON_MTD_DELETE$, objDoc ); goSub checkErr
      
   end else
      goSub checkErr
   end
   
   return ""
   
   
checkErr:

   if get_Status( errText ) then
      call set_Status( SETSTAT_OK$ )   
      debug
   end

return

Example 2:

Function Google_Maps_Address_latLng_Example(address)
     /*
     **  Example of calling google maps api to get lat_lng of an address
     **
     **  03-17-25  rjc  Created
     */

     #pragma format_indent_comments
     $insert logical
     $insert rti_RJSON_Equates
     $Insert rti_Text_Equates

     Declare Function ole_getwebpage, rti_get_cfg

     retval = null$
     lats = null$
     lngs = null$
     If Assigned(address) Else address = null$
     If address == null$ Then
          Return null$
     End

     apikey = rti_get_cfg("GOOGLE_MAPS_API_KEY")

     * Constuct the URL - use URLENCODE to escape special characters
     geocode_url = "https://maps.googleapis.com/maps/api/geocode/json"
     geocode_url := "?address=":Iconv(address, '[URL_FORMAT]')
     geocode_url := "&key=":apikey

     * CAll Google's API, get a JSON response
     http_method = "GET"
     payload = null$;headers = null$;credentials = null$;timeoutInfo = null$;responseFile = null$
     geocode_json = ole_getwebpage( geocode_url, http_method, payload, credentials, headers, timeoutInfo)

     * Parse the JSON
     hJson = rti_rjson(RJSON_MTD_PARSE$,geocode_json)

     *---
     * Need to parse out location.lat, location.lng
     * This particular google API call returns an array of lat/lng values.
     * I want to make a list of the lats and lngs
     * Below are two equivalent approaches.  Choose one.
     *---

     ***
     * Method 1 - Iterate accross the array using the main JSON object
     ***

     * itemcount on the 'results' item, specify a path relative to the main item

     itemCount = rti_rjson(RJSON_MTD_GETITEMCOUNT$, hJson, "results")

     * We are working with the main hJson object, so spectify full path
     * Array index is 0 based, so subtract 1
     For i = 1 To itemcount
          lats<i> = rti_rjson(RJSON_MTD_GETITEMVALUE$, hJson, "results[" : i - 1 : "].geometry.location.lat")
          lngs<i> = rti_rjson(RJSON_MTD_GETITEMVALUE$, hJson, "results[" : i - 1 : "].geometry.location.lng")
     Next

     *----
     * Method 2 - Alternative approach to iterating across the array
     * get the handle of the results item, specify a path to relative to that item
     *----
     hRslt = rti_rjson(RJSON_MTD_GETITEM$, hJson, "results")

     * Do we have an array [1,2,3]  or object {"one":1,"two":2,"three":3} ?
     itemType  = rti_rjson(RJSON_MTD_GETITEMTYPE$, hRslt)

     * use the appropriate method to get a list of handles for all the children in 'results'
     * itemElements will be an fm delimited array of childitem handles
     itemElements = ""
     If itemType == RJSON_TYPE_ARRAY$ then
          itemElements = rti_rjson(RJSON_MTD_GETARRAYELEMENTS$, hRslt)
     End Else
          itemElements = rti_rjson(RJSON_MTD_GETOBJECTMEMBERS$, hRslt)
     End

     * Get the length or results. Since handle is for 'results', no need to specify a sub path
     * note, could also fieldcount(itemElements)
     itemCount = rti_rjson(RJSON_MTD_GETITEMCOUNT$, hRslt)

     * Iterate across the child items, get the values
     * In this example, hItem is the handle for an element in the array, e.g. results[2], so path is relative to the item, not results[i]
     *
     For i = 1 To itemCount
          * itemElements is a dynamic array of handles
          hItem = itemElements<i>

          lats<i> = rti_rjson(RJSON_MTD_GETITEMVALUE$, hItem, "geometry.location.lat")
          lngs<i> = rti_rjson(RJSON_MTD_GETITEMVALUE$, hItem, "geometry.location.lng")

     Next


     * Release the memory used by the object JSON object

     unused = rti_rjson(RJSON_MTD_DELETE$, hJson)

     * Return lat / lng
     retval = lats:@vm:lngs


Return retval