XML-RPC

eXtensible Markup Language Remote Procedure Call

A protocol that enables software running on different operating systems and environments to make remote procedure calls over the internet using HTTP as the transport protocol and XML for encoding the data. As an example, here’s how it works in the WordPress context:

1. A client application sends an XML request to a WordPress site
2. The WordPress site processes the request and sends back an XML response

Let me show you an example of XML-RPC communication with WordPress.

<?xml version="1.0"?>
<methodCall>
  <methodName>wp.getPosts</methodName>
  <params>
    <param>
      <value>
        <struct>
          <member>
            <name>blog_id</name>
            <value><int>1</int></value>
          </member>
          <member>
            <name>username</name>
            <value><string>admin</string></value>
          </member>
          <member>
            <name>password</name>
            <value><string>mypassword123</string></value>
          </member>
          <member>
            <name>number</name>
            <value><int>5</int></value>
          </member>
        </struct>
      </value>
    </param>
  </params>
</methodCall>

<?xml version="1.0"?>
<methodResponse>
  <params>
    <param>
      <value>
        <array>
          <data>
            <value>
              <struct>
                <member>
                  <name>post_id</name>
                  <value><string>123</string></value>
                </member>
                <member>
                  <name>post_title</name>
                  <value><string>Hello World!</string></value>
                </member>
                <member>
                  <name>post_content</name>
                  <value><string>Welcome to WordPress...</string></value>
                </member>
              </struct>
            </value>
          </data>
        </array>
      </value>
    </param>
  </params>
</methodResponse>

While XML-RPC was widely used in WordPress for remote management and third-party application integration, modern WordPress development has largely shifted towards using the REST API, as it’s more secure and easier to work with. However, XML-RPC is still supported for backward compatibility.

• Abbreviation: XML-RPC