1. XML-RPC

2. General Procedure Call
Procedures or functions normally exist within the same machine / same memory space as the main function
Memory space
Main function
Sub-function 1
Sun-function 2
Sub-function 3

3. Remote Procedure Call (RPC)
Procedures are not reside in the same memory space or same machine as the main function
Computer 1
Computer 2
Network
Remote procedure
Main function

4. Remote Procedure Call (RPC)
Characteristics
It is a protocol the enable a program to request a service which is located in another computer (make a remote function call) in the network the same way as calling local functions
Synchronous operation
Resource sharing is the main goal
Utilize client/server model
No compatibility between RPC from different language

5. XML-RPC
Use XML to format request message (function call) and response message (return value)
Break the language boundary
Utilize HTTP
Founded ~1998

6. XML-RPC Technical XML-RPC Data model XML-RPC Request structure
XML-RPC Response structure

7. XML-RPC Data Model 6 basic types
int or i4 : 32-bit integer
double : 64-bit floating point
boolean : 1 (true) or 0 (false)
string
datetime.iso8601 : YYYYMMDDTHH:MM:SS
base64 : base64 encoding
Basic types are always enclosed in <value>

8. Basic Type examples
<value><int>100</int></value>
<value><double>3.14</double></value>
<value><boolean>1</boolean></value>
<value><string>an example</string></value>
<value><datetime.iso8601> T09:00:00 </datetime.iso8601></value>

9. XML-RPC Data Model 2 complex types Arrays Structs
Array can contain mixtures of different types
Structs

10. Complex type example
<value> <array> <data> <value><int>10</int><value> <value><int>20</int><value> </data> </array> </value>

11. Complex type example
<value> <array> <data> <value><int>10</int><value> <value><string>abcd</string><value> </data> </array> </value>

12. Complex type example
<value> <array> <data> <value><int>10</int><value> <value><int>20</int><value> </data> </array> </value> <value><int>30</int><value> <value><int>40</int><value>

13. Complex type example
<value> <struct> <member> <name>firstname</name> <value><string>John</string></value> </member> <name>lastname</name> <value><string>Doe</string></value> </struct> </value>

14. XML-RPC Request Structure
<?xml version=“1.0” ?> <methodCall> <methodName>…………..</methodName> <params> <param> <value>……</value> </param> …. </params> </methodCall>
Use HTTP POST method

15. XML-RPC Response Structure
<?xml version=“1.0” ?> <methodResponse> <params> <param> <value>……</value> </param> </params> </methodResponse>
Only one <param> is allowed
If it is a void function -> modify it to return value for example return 1 if successfully execute
Return value is required

16. XML-RPC Response Structure
<?xml version=“1.0” ?> <methodResponse> <fault> <value>……</value> </fault> </methodResponse>

17. XML-RPC Example - Function

18. XML-RPC Example - Server

19. XML-RPC Example - Client