XML-RPC

From Wikipedia, the free encyclopedia

XML-RPC is a remote procedure call protocol which uses XML to encode its calls and HTTP as a transport mechanism. [1]

Contents

[edit] Overview

XML-RPC is a very simple protocol, defining only a handful of data types and commands[2], and the entire description can be printed on two pages of paper. This is in stark contrast to most RPC systems, where the standards documents often run into the hundreds of pages and require considerable software support in order to be used.

[edit] History

XML-RPC was first created by Dave Winer of UserLand Software in 1998 with Microsoft. As new functionality was introduced, the standard evolved into what is now SOAP.

[edit] Usage

Some people still prefer XML-RPC to SOAP because of its simplicity, minimalism, and ease of use.

JSON-RPC is similar to XML-RPC.

[edit] Data types

Name Tag Example Description
array 
<array>
  <data>
    <value><i4>1404</i4></value>
    <value><string>Something here</string></value>
    <value><i4>1</i4></value>
  </data>
</array>
Array of values, storing no keys
base64 
<base64>eW91IGNhbid0IHJlYWQgdGhpcyE=</base64>
Base64-encoded binary data
boolean 
<boolean>1</boolean>
Boolean logical value (0 or 1)
date/time 
<dateTime.iso8601>19980717T14:08:55</dateTime.iso8601>
Date and time in ISO 8601 format
double 
<double>-12.53</double>
Double precision floating point number
integer 
<i4>42</i4>

or

<int>42</int>
Whole number, integer
string 
<string>Hello world!</string>
String of characters. Must follow XML encoding.
struct 
<struct>
  <member>
    <name>foo</name>
    <value><i4>1</i4></value>
  </member>
  <member>
    <name>bar</name>
    <value><i4>2</i4></value>
  </member>
</struct>
Associative array
nil 
<nil/>
Discriminated null value; an XML-RPC extension

[edit] Examples

An example of a typical XML-RPC request would be:

<?xml version="1.0"?>
<methodCall>
  <methodName>examples.getStateName</methodName>
  <params>
    <param>
        <value><i4>40</i4></value>
    </param>
  </params>
</methodCall>

An example of a typical XML-RPC response would be:

<?xml version="1.0"?>
<methodResponse>
  <params>
    <param>
        <value><string>South Dakota</string></value>
    </param>
  </params>
</methodResponse>

A typical XML-RPC fault would be:

<?xml version="1.0"?>
<methodResponse>
  <fault>
    <value>
      <struct>
        <member>
          <name>faultCode</name>
          <value><int>4</int></value>
        </member>
        <member>
          <name>faultString</name>
          <value><string>Too many parameters.</string></value>
        </member>
      </struct>
    </value>
  </fault>
</methodResponse>

[edit] Implementations

[edit] C++

[edit] Java

[edit] Jabber

[edit] Other

[edit] See also

[edit] References

  1. ^ Simon St. Laurent, Joe Johnston, Edd Dumbill. (June 2001) Programming Web Services with XML-RPC. O'Reilly. First Edition.
  2. ^ Dave Winer. (June 15, 1999) XML-RPC Specification UserLand Software, Inc.

[edit] External links