This document lists in a human readable form the rules for creating an Huddl Formation Definition (HFD) file as codified in:
The Huddl W3C schema defines:
The Huddl Schematron document was introduced to enforce additional constraints that are not supported by the W3C schema.
Each HFD file has exactly one schema as root element.
The fact that schema is the only valid root element is implemented by the Schematron constraint check_schema_is_root.
The Huddl W3C schema enforces that:
A format element contains all the elements required to describe a given data format.
A format element has:
In case that a schema has more than one format elements, each of them must have unique name and scope attributes (schema rules: uniqueFormatName and uniqueFormatScope).
The optional prolog element contains general information (metadata) about the data format.
A prolog element has a title and several optional elements: many possible alternate titles, a document number, a reference date, the organization that maintains the format, the revision history.
The content element provides the actual data format description. The description is split in:
The block element provides a description of a format data block (e.g., a Kongsberg EM Series datagram).
There are a variety of pre-defined common data structures that can be used (multiple times) to describe the content of a data block:
A block element can have other block elements nested. It is implemented by definining the nested block as a type in the blockType element.
In adjunct, additional information to the size of the data block can be optionally provided using one of the two following elements:
The stream element provides a description of a format stream (e.g., a Kongsberg EM Series format release).
The stream element has the following attributes:
The stream element describes:
The topBlock element has three mandatory attributes:
For each stream, the topBlock must have an unique alias attribute.
tags: huddl; schema; rules