Adobe 38039927 Extended User Guide - Page 265

ADOBE FIREWORKS CS3 261 Extending Guide Data type Node name server obj object string string void void Example Description The server object data type. The value attribute is set to the object ID. The class attribute is optional. The server always specifies the object class when sending replies to the client. The client, however, is not required to specify the class when sending server object nodes to the server. The class attribute tells the client what properties and methods are available on an object. A string data type. It can contain a UTF-8-encoded string. If you include special characters, you must "escape" them (indicate that they are part of the string) according to the method described in the XML Data Model (from http://www.w3.org/XML/Datamodel.html). Most XML writing packages automatically do this. No value; no type. Cannot have any attributes or subelements. Parameters Parameters are simply data nodes with an order attribute. The order attribute identifies the order in which the parameters should be processed for the server. In this way, the RPC client can use any XML client library to build parameters in any order, and the RPC server retains the correct parameter order. The first parameter should have the order attribute set to 0; the second, to 1; and so on, as in this example: The set operation requires only one parameter, and the func operation may have zero or more parameters. RPC server XML replies After the RPC server processes an XML request, it packages the result as an XML fragment and sends it back to the client. If an error occurred during processing, the server returns an error code in the result XML. Otherwise, the reply node contains a single data node with the result of the operation. If the request doesn't require a return value, the reply node contains either a single void data node or no children nodes. For example, here is a successful reply: Here is a successful reply with a server object: Note: When the server returns a server object, it automatically retains the object on the client's behalf. That is, the object returned to the client is not destroyed until the client releases it with a release request, or until the client disconnects from the server. Therefore, the client should release a server object as soon as the client has finished sending requests related to that object (when the client is done "using" the object). Error codes If the server encounters an error when processing a request, the reply node (with the node name return) contains at most one error attribute, as in this example: