MACROMEDIA DREAMWEAVER MX 2004-EXTENDING DREAMWEAVER, Manual

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78 Chapter 3: Cross-Product Extensions
Fireworks RPC transactions pass XML between an RPC client and the Fireworks RPC server
built into Fireworks MX 2004. The RPC client is any supported program that connects to
Fireworks through a TCP stream on port 12124. The Fireworks RPC server is the internal code
that listens on TCP port 12124 and then handles client requests. During the RPC transaction,
information flows from client to server:
Note: The RPC client is not required to disconnect after each XML request. The RPC client can keep
the connection open and send additional XML requests. However, only one XML request can be
outstanding at one time. In other words, the RPC client cannot send a second request until it receives
a reply to the first request.
RPC client XML requests
The XML request contains four pieces of information for Fireworks:
•
The type of operation to perform
•
The name of the operation to perform
•
The object on which the operation is performed
•
Any parameters the operation needs
Note: XML requests are specially formatted XML document fragments, not full XML documents.
XML requests are sent to the server in UTF-8 encoding and terminated with the null (0) character.
Logically, requests contain two parts: the envelope and the parameters. The envelope specifies the
the requested operation (for instance,
get
or
set
) and the object that the operation is performed
on. The parameters (strings, integers, arrays, and so on) specify how the operation happens. The
envelope tag contains the parameter tag, as follows:
< envelope >< parameter /></ envelope >
SERVER
2
Accept TCP connection
4
Process XML request
5
Send XML reply
8
Accept TCP
disconnect
CLIENT
1
Establish TCP connection
on port 12124
3
Send XML request
6
Process XML reply
7
Disconnect TCP
connection