The validation service supports multiple modes. In the conformance test mode it is checked whether the individual streams of the ODF document, like content.xml or styles.xml, are valid with respect to the OpenDocument schema after the pre-processing of foreign elements and attributes described in section 1.5 of the OpenDocument specification has been applied. This comes very close to a conformance test for ODF documents, but not all provisions for conforming documents are checked.

The validation mode is like the conformance mode, except that the pre-processing of foreign elements and attributes is omitted. Which means that a document only passes this test if it does not contain any elements or attributes not defined by ODF. The only exception are elements and attributes in the meta data and formatting properties, because the ODF schema allows arbitrary elements and attributes to appear here.

The third mode is the strict validation mode. In this mode, the streams are validated with respect to the strict variants of the ODF schema. The difference to the regular schemas is that meta data and formatting properties are restricted to those elements and attributes that ODF itself defines. This mode is useful if you want to check that a document contains only elements and attributes that ODF defines, but no extensions. You should use this mode in particular if you do development on OpenOffice.org (or any other ODF implementation), and want to make sure that your document does not only validate in regards to the ODF schema, but also does not use any extensions. Like the validation mode, this most is more restrictive than a conformance test. That means that errors may be reported for documents that are actually conforming to the ODF specification.

The validation service is based on a Java ODFValidator tool, which again is based on MSV. This tools is available in source code and provides also a command line interface. I will describe this tool in a separate post next week or so.

A last remark: When you use the ODF Validation service to check arbitrary documents you have on you hard drive and get error messages, please consider that these documents may not have been stored by an up-to-date version of OpenOffice.org or other ODF applications. That means you may get error messages for issues that have have been resolved already. We at OpenOffice.org take these issues serious and aim to resolve them as soon as possible (which does not mean that it is always possible to resolve them in the next release). But resolving an issues in OpenOffice.org of cause does not change the documents that have already been stored.

One reason we provide this service is actually that we want you, the community, to help us to find issues in OpenOffice.org. Therefore, if you find errors in documents that have been stored by the current OpenOffice.org versions, please submit an issue. We are also working on some rules that help us to link validation error messages to issues. But this will be a topic for another post, too.