AppML

AppML was an open source initiative from W3Schools for describing Internet applications. The name is a contraction of Application Markup Language.

AppML used the HTML, CSS, and XML Internet standards to describe applications. AppML was a declarative language, and AppML applications were self-describing.

History

In 1999, the staff at W3Schools began developing AppML.

In September 2000, a development project for a large Norwegian customer was started. The goal of the project was to convert a huge information system from a Windows desktop application to a modern Internet application using only AppML. The new AppML-based system was launched in 2001, several months before schedule, and it was one of the first commercial available AJAX applications. The project was a success, with development time reduced by 75% compared to ordinary web development. Since then, hundreds of new applications have been added, and AppML now covers over 1000 running applications.

In December 2006, W3Schools decided to offer AppML to the public, as an open source product, free of charge.

In mid September 2007, all of the AppML content has gone offline. Subsequent emails to help@refsnesdata.no reveal that AppML has been quietly discontinued with no notice or publication¹.

Original Design Goals

• AppML must run over the Internet
• AppML must be platform independent and use Internet standards only, and be compatible with XML and XHTML
• AppML must support a variety of application needs
• AppML must be self-describing
• AppML applications must be easy to develop, maintain and change
• AppML applications must be future proof

Execution

An example AppML description looks like:

<appml>
  <title>CUSTOMERS</title>
  <database>
    <connection>northwind</connection>
    <keyfield type="text">customerid</keyfield>
    <maintable>customers</maintable>
    <sql>Select CompanyName, City, Country from Customers</sql>
  </database>
  <filters>
    <query>
      <field>CompanyName</field>
    </query>
  </filters>
   <htmlform />
  <htmllist />
  <htmlreport />
</appml>

To execute an AppML description, an AppML web service was required. The purpose of the web service was to execute the application based on the AppML description.

External links

• ¹ AppML has been officially discontinued
• Former official website for AppML language