Customize XML serialization with WSName and XMLName

Use XML serialization attributes to customize serialization at runtime and improve the readability of the XML output.

Formatting XML output with WSName and XMLName

This sample REST function returns a list of users to the client in XML format. The function's return value defines a dynamic array of profileType that is set with the following attributes:

WSName="All_users_list" sets the root node for the output to <All_users_list>.
WSMedia = "application/xml" sets the output to XML.
XMLName="User" maps each element of the profileType record with the <User> tag.
The XMLOptional attribute specifies that <User> elements with NULL values are omitted from the XML document. For other options of working with NULL values, see the XMLNillable attribute.

If you do not use the WSName and XMLName attributes to format the XML output, names derived from DVM names such as "rv0", "rv1", and so on are used.

TYPE profileType RECORD
     id INTEGER,
     name VARCHAR(100),
     email VARCHAR(255),
     ccode VARCHAR(3)
     # ...
   END RECORD

PUBLIC FUNCTION getUsersList()
  ATTRIBUTES (WSGet,
              WSPath = "/users/xml",
              WSDescription="Get list of users and output in XML format"
              )
  RETURNS (
    DYNAMIC ARRAY ATTRIBUTES(WSName = "All_users_list",
                            WSMedia = "application/xml") OF profileType
                            ATTRIBUTES(XMLName = "User", XMLOptional)
          )

    DEFINE usersList DYNAMIC ARRAY OF profileType
    DEFINE i INTEGER = 1

    # code to get users
     DECLARE userCurs CURSOR FOR SELECT * FROM users ORDER BY users.name
     FOREACH userCurs INTO arr[i].*
       LET i = i+1
     END FOREACH
     CALL arr.deleteElement(arr.getLength())
     # Remove the empty element implied by reference in FOREACH loop

  RETURN usersList
END FUNCTION

The output in the XML document contains the tags specified by the attributes WSName and XMLName: If the output is viewed in an XML viewer, it would display as shown.

<All_users_list>
  <User>
    ... record content
  </User>
  <User>
    ... record content
  </User>
  ...
</All_users_list>