Define multiple versions for an operation

Specify which API versions an operation applies to using the WSVersion attribute.

You can maintain multiple versions of the same operation when changes are not backward compatible. Each version is implemented as a separate function, with a unique WSVersion value.

The following example shows an operation (prices_v1v2) that is available in two versions: v1 and v2.

Multiple versions

IMPORT com

PUBLIC DEFINE userError RECORD ATTRIBUTES(WSError = "User error")
  message STRING
END RECORD

PUBLIC FUNCTION prices_v1v2(nb INTEGER ATTRIBUTES(WSParam))
  ATTRIBUTES (WSGet,WSPath = "/prices/{nb}",
               WSDescription = "Returns the price of an item for API v1 and v2",
               WSThrows = "404:item not found", 
               WSVersion = "v1,v2") 
  RETURNS (INTEGER)
   DEFINE price DECIMAL(10,2)
    TRY
      SELECT unit_price INTO price FROM unit_pricing
        WHERE unit_id = nb
      IF sqlca.sqlcode = 100 THEN
        CALL com.WebServiceEngine.SetRestError(404,NULL)
      END IF
    CATCH
      LET userError.message = SFMT(" - SQL error:%1 [%2]",
                                   sqlca.sqlcode, SQLERRMESSAGE)
      CALL com.WebServiceEngine.SetRestError(505,userError)
    END TRY
    RETURN price
END FUNCTION

When generating the OpenAPI document, GWS includes this operation in any version where it is declared. In this example, the operation appears in both v1 and v2:

http://myhost/gas/ws/r/myGroup/myXcf/myService?openapi.json&version=v1
http://myhost/gas/ws/r/myGroup/myXcf/myService?openapi.json&version=v2