MEDIN Standards Workshop Standards / XML / Validation / Transformation / ESRI

Introduction –XML –Schema and Validation XSD Schema Schematron –Transformation Stylesheets –ESRI ArcGIS –Search Pa ge 2

XML

Extensible Markup Language (XML) –A metamarkup language –The basic unit is called an element –Apparently similar to HTML but… Pa ge 4 element value Element Attribute Opening tag Closing tag

Metamarkup? What does metamarkup mean? –There is no predefined and fixed set of tags for XML –XML allows implementers to define their own set of tags to meet their needs Pa ge 5 Examples Office Open XML (ISO/IEC 29500) Geography Markup Language (ISO 19136)

Markup – ESRI ArcGIS 10 XML Pa ge 6 Title

Markup – ISO XML Pa ge 7 Title creation

Well-Formed XML has strict rules, e.g.: –There must be one, and only one root element –All elements must have an opening and closing tag –Element names are case sensitive: is different from –XML conforming to the rules is said to be well-formed Pa ge 8

Well-Formed Pa ge 9 Title Title Summary No closing tag Opening and closing tags are different Two root elements

Structure The markup defines data structure: –It signifies which elements are associated –It can define semantics: –It says nothing about how to display data (there are exceptions to this rule) Pa ge

XML is machine readable And… –Human readable… honestly Pa ge 11

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Schema and Validation

Schema Schemas document the elements that are permitted in an XML application –XML that conforms to a schema is said to be schema-valid –XML that does not conform to a schema is said to be invalid Pa ge 14

XML Schema Definition Language Pa ge <xs:element name="title" type="gco:CharacterString_PropertyType"/> <xs:element name="alternateTitle" type="gco:CharacterString_PropertyType" minOccurs="0" maxOccurs="unbounded"/> <xs:element name="date" type="gmd:CI_Date_PropertyType" maxOccurs="unbounded"/>...

Markup – ISO XML Pa ge 16 Title creation

Schematron Schematron is: –A schema language for XML Document Schema Definition Language (DSDL) –Written in XML –It’s an ISO Standard – ISO Find out more at: Pa ge 17

Why use Schematron? XSD schema is unable to test some constraints: –The ability to specify a choice of attributes –The ability to vary the content model based on the value of an element or attribute (this sort of constraint is common in the ISO logical model) Implementing profiles (e.g. MEDIN): –With Schematron there’s no need to edit the underlying standardised XSD Pa ge 18

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What’s in a name? Schematron’s a funny name… –It’s just a reaction to the common use of acronyms – MEDIN ;-) – according to the author, Rick Jelliffe –It was originally to be called the Pink Schematron apparently see 21&v=1 Pa ge 20

Validation Workflow Pa ge 21 XSD Schema ValidationSchematron Validation

Validation Tools Pa ge 22 Select profile XSD Schema Schematron schemas

Transformation

XSLT Extensible Stylesheet Language Transformations (XSLT) –Specifies rules for transforming one XML instance into another XML instance –The output XML instance will have a different structure from the input XML instance Pa ge 24

ESRI XML to MEDIN XML MEDIN XML must be follow the ISO XML encoding –Users may wish to use other software to create and manage metadata (e.g. ESRI desktop GIS) –ESRI software manages metadata using XML –The XML does not following the ISO standard –The XML can be transformed to ISO –MEDIN provides resources to support this Pa ge 25

Stylesheet Tools Pa ge 26

ESRI ArcGIS

Versions ArcGIS 9 –FGDC / ISO ArcGIS 10 –ESRI Core Metadata –Both use XML encoding –The encodings are slightly different –Why the change at version 10? Pa ge 28

ESRI ArcCatalog – Options Pa ge 29

ESRI ArcCatalog Pa ge 30

Transformation Pa ge 31 ArcGIS 9 Metadata ArcGIS 10 Metadata MEDIN Metadata Transformation e.g. Internal usee.g. External / Publish to DAC

Transform Options Use MEDIN stylesheets –ArcGIS 9 version –ArcGIS 10 version (or the Validate button) Implementation –Any XSL stylesheet processor (version1.0), e.g: ArcGIS 9 or 10 ArcToolBox Metadata Maestro Pa ge 32