1. Forest Markup / Metadata Language FML
For Discussion among NEFIS Partners
Tim Richards
EFI / Conservation Technology Ltd
NEFIS Midterm Meeting
Vienna, March 2004
NEFIS Mid-term Meeting
Vienna May 2004
FML

2. Interoperability & Markup Languages - Revisited
Interoperability – what is it?
XML – what is it?
XML Schema – what is it?
FML – what could it be?
NEFIS Mid-term Meeting
Vienna May 2004
FML

3. Interoperability – what is it?
The ability for two or more (independently-developed) (software) components to:
interact meaningfully
Communicate meaningfully
Exchange data or services
[After Moh in Bonn]
NEFIS Mid-term Meeting
Vienna May 2004
FML

4. Achieving Interoperability
Interoperability is difficult to achieve because of heterogeneity -
Components are:
written in different programming languages
running on different hardware platforms
running on different operating systems
using different data representations
using different control models
implementing different semantics or semantic interpretations
implementing duplicate functionality
implementing conflicting functionality
[After Moh in Bonn]
NEFIS Mid-term Meeting
Vienna May 2004
FML

5. NEFIS Mid-term Meeting
XML – what is it?
eXtensible Markup Language
Meta markup language for text documents
No fixed set of tags
Data are included as strings of text which are surrounded by text markup that describes the data, e.g.
<name>Cyril Hart</name>
element
markup tag
data
From the spec:
Extensible Markup Language, abbreviated XML, describes a class of data objects called XML documents and partially describes the behavior of computer programs which process them. XML is an application profile or restricted form of SGML, the Standard Generalized Markup Language [ISO 8879]. By construction, XML documents are conforming SGML documents.
XML documents are made up of storage units called entities, which contain either parsed or unparsed data. Parsed data is made up of characters, some of which form character data, and some of which form markup. Markup encodes a description of the document's storage layout and logical structure. XML provides a mechanism to impose constraints on the storage layout and logical structure.
NEFIS Mid-term Meeting
Vienna May 2004
FML

6. NEFIS Mid-term Meeting
XML
XML is a meta-markup language
XML is completely open, you can define whatever tags you want to. There is a need to constrain it.
Can be used to define an XML dialect that is specific to a subject domain, such as forests, by a community agreeing on a standard set of tags with defined relationships. The community defines the XML dialect.
XML is extensible and can be easily extended as and when required.
NEFIS Mid-term Meeting
Vienna May 2004
FML

7. Related XML Technologies
XML is straightforward but belongs to a complex set of related technologies, including:
XML Schema Definition – provides constraints for XML documents
Document Type Definitions
eXtensible Stylesheet Language – XSL
XQuery
XPath
XLinks
XPointers
XSL Formatting Objects (XSL-FO)
NEFIS Mid-term Meeting
Vienna May 2004
FML

8. NEFIS Mid-term Meeting
Uses of XML
Uses of XML
As a document format
As a data format
For storing data / metadata
For transmitting data / metadata between systems
NEFIS Mid-term Meeting
Vienna May 2004
FML

9. NEFIS Mid-term Meeting
XML Dialects
Examples of XML dialects include:
Geography Markup Language (GML)
ESRI’s ArcXML
Scaleable Vector Graphics (SVG)
MathML
Ecology Metadata Language (EML)
Forest Markup Language ? What is that?
NEFIS Mid-term Meeting
Vienna May 2004
FML

10. NEFIS Mid-term Meeting
FML
What could FML do for the forest community?
FML could provide:
an explicit and extensible definition of forest metadata – a standard
a platform independent medium for the transfer of forest metadata - interoperability
an explicit and extensible meta description for forest data – a standard
A platform independent medium for the transfer of forest data - interoperability
NEFIS Mid-term Meeting
Vienna May 2004
FML

11. NEFIS Mid-term Meeting
Purpose of FML
“To provide the ecological forest community with an extensible, flexible, metadata standard for use in data analysis and archiving that will allow automated machine processing, searching and retrieval.”
Source – Ecological Metadata Language (EML)
EML is defined in XML Schema as a set of related modules.
NEFIS Mid-term Meeting
Vienna May 2004
FML

12. NEFIS Mid-term Meeting
FML Features
FML’s main features could be:
Modularity – thus extensible
Detailed Structure – to enable machine processing
Compatibility – where possible adopts syntax of other metadata standards – DC, GML, FGDC, etc
Strong Typing – by being implemented in XML Schema
Difference between the content model (English) and the syntax implementation (XML)
[After the EML features]
NEFIS Mid-term Meeting
Vienna May 2004
FML

13. NEFIS Mid-term Meeting
DC expressed in XML
Example dc record in XML
dc: Dublin Core “Namespace”
NEFIS Mid-term Meeting
Vienna May 2004
FML

14. NEFIS Mid-term Meeting
DC expressed in XML
DC publisher element qualified with a NEFIS address and namespace
extensibility
NEFIS Mid-term Meeting
Vienna May 2004
FML
How to specify the tags ...

15. NEFIS Mid-term Meeting
XML Schema
XML Schema
“... formalisation of the constraints, expressed as rules or a model of structure, that apply to a class of XML documents” – a definition of FML
Documentation
used to document xml definitions and provide an explicit reference
Validation
used to validate XML documents to ensure they conform to the reference
NEFIS Mid-term Meeting
Vienna May 2004
FML

16. NEFIS Mid-term Meeting
Simple DC XML Schema
Link to DC Simple Schema
DCMI XML Recommendation
NEFIS Mid-term Meeting
Vienna May 2004
FML

17. XML Validation – conforms to the standard
DC Schema
Simple DC
Simple DC + FML
FML Schema
NEFIS Mid-term Meeting
Vienna May 2004
FML

18. NEFIS Mid-term Meeting
Dynamic Metadata Tool
Online
FML Schema
Dynamic Metadata
Software
Tool
Information
Resource
interprets
describes
produces
Structure validated
against
FML
Metadata
Document
NEFIS Mid-term Meeting
Vienna May 2004
FML

19. NEFIS Mid-term Meeting
Dynamic Data Tool
Online
FML Schema
Data Export
Tool
Information
Resource
interprets
extracts
produces
Structure validated
against
FML
Data
Document
NEFIS Mid-term Meeting
Vienna May 2004
FML

20. Natural Progression from EFIS Metadata
Metadata Content In
Metadata Definition
efisSchema.xml
XML Parser
HTML
Form
XML Constructor
RDBMS
Metadata Content
Repository
HTML
Form
XML Parser
NEFIS Mid-term Meeting
Vienna May 2004
FML
Metadata Out

21. For example : EML Modules
Ecological Metadata Language
Root level
Metadata container & base information
Top level resources
Dataset module
Literature module
Software module
Protocol module
Supporting modules
Access module
Physical module
Party module
Coverage module
Methods module
Data organisation
Entity module
Attribute module
Constraint module
Entity types
Data table module
Spatial raster module
Spatial vector module
Stored procedure module
Utility modules
Text module
Dependency chart
FML could be comprised of a similar set of modules, streamlined for forests rather than ecology.
For example FML might include a module on forest models.
NEFIS Mid-term Meeting
Vienna May 2004
FML

22. NEFIS Mid-term Meeting
Open Source EML Tools
EML Schema
Morpho Metadata Client Tool
dynamically generated from the EML Schema
Metacat Metadata Server
XML database
NEFIS Mid-term Meeting
Vienna May 2004
FML

23. Open FML Q’s: For Discussion
Q. Is XML/FML relevant to NEFIS and the wider EU forest agenda?
A. Suggest yes…
Q. Would FML enhance interoperability issues in the European (and wider) forest community?
Q. Are the problems that are addressed syntactic or semantic?
A. Mainly syntactic, some semantics?
[After Moh in Bonn]
NEFIS Mid-term Meeting
Vienna May 2004
FML

24. NEFIS Mid-term Meeting
Where now FML?
If the EU (or wider) forest community wants FML it should:
Make a strong case for FML and FML Tools
See what is out there that can already be used – such as EML
Secure funding to design and implement FML and FML Tools
Make it an Open Source Project from the outset !
NEFIS Mid-term Meeting
Vienna May 2004
FML