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is the port_of_landing XML element. It provides the port code "SIT". The attributes associated tell any person or system reading the document (but not eLandings) that the code represents the port of Sitka, and that the NMFS IFQ port code for Sitka is 168. The eLandings system never reads attributes, and they should never be used to try to convey information to the system. The eLandings system reads only the element data, and is able to derive the attributes itself.

XML Data Structure

The data structure of each type of XML document in eLandings is unique, but the documents share some common features.

Schema Version

Messages

Report Data

XML Schema

The XML schema is used to describe the format of XML documents in eLandings. Since the format can be enhanced over time the XML schema includes a version number that uniquely identifies that version of the schema, and that can be used to communicate to the system the version of the schema that was used to create any particular landing report file or XML document.

The XML schema can be used by a variety of tools to create code that will read and write XML documents.

XML Schema Versioning

Whenever the eLandings developers need to add a data element they modify the XML schema. They also increment the schema version number, and modify the eLandings codebase to add forward and backward compatibility logic to handle differences in documents made with different versions of the schema.