ga2 1 lecture1

Dr.-Ing. Peter Korduan GI Advanced

OGC Standardisation 1

Rostock University, Chair for Geodesy and Geoinformatics X 2007

GIS Advanced TopicsPart 3: OGC Standardization

Interoperability and Web Service Specifications

Standardisation

WMS

WFS

WCS

WMC

Other Services

SDI

University of Rostock, Dr.-Ing. Peter KorduanE-Mail: [email protected]

Rostock University, Chair for Geodesy and Geoinformatics

Motivation

• Open Geospatial Consortium• Interoperability and Web Service Specifications

• In the module• you will become familiar with OGC Standardization in general and with

Web Service Specifications• After this module

• you understand how Web Services work• you are able to send requests to the most important Service Types

WMS, WCS and WFS• you can construct spatially and thematic filter to get standardized vector

data documents• you can read and understand GML Documents• you know how UMN MapServer works as WMS/WFS Server and Client




Content

• Introduction• Standardization Process

• ISO• OGC• Abstract Specifications

• Web Map Service (WMS)• Styled Layer Descriptor (SLD)

• Web Coverage Service (WCS)• Web Feature Service (WFS)

• Geography Markup Language (GML)• Filter Encoding (FE)

• Web Map Context Document (WMC)

• Other Services and specification activities

Parts of this presentation are derived from Tom Kralidis ms_ogc_workshop documentation


Introduction - GIS today

• Still manually exchange of spatial data• Different products, formats, data availability, regulations

Municipalityservices

Logistics/transport

National mapping

Land register

Utility and supply network

Natural resources Operation control unit

ConstructionOGC (1999)

Introduction




Introduction - GIS tomorrow

• New models for spatial data access• Common interfaces, services, interoperability

Catalogueview

ParcelsStreetsImageryTopography

...

Stadt See

Integrated view

privateproviders

Communes County Country

DataMeta data

DataMeta data

DataMeta data

Data Meta data

Queries on data fromdifferentsources

Clearinghouse

Geodata-Searchengines,similiar to HTML-Search-engines in WWW

Stadt See

Internet

OGC (1999)

Introduction


Interoperability problem

Prog 1

Prog 2

Prog n

Prog 1Prog 2

Prog n

interoperableinterface

Introduction

Client1 Client2 Client3

Server1 Server2 Server3

Client1

Server1 Server2 Server3

Client2




Geospatial Interoperability

“Geospatial Interoperability is the ability for two different software systems to interact with geospatial information. Interoperability between heterogeneous computer systems is essential to providinggeospatial data, maps, cartographic and decision support services, and analytical functions. Geospatial interoperability is dependent on voluntary, consensus-based standards...

These geospatial standards are essential to advancing data access and collaborations in e-Government, natural hazards, weather and climate, exploration, and global earth observation.”

Source: Geospatial Interoperability (GI) Return on Investment Study Report , NASA, April 2005, http://gio.gsfc.nasa.gov/docs/ROI%20Study.pdf

Introduction


Provider AServer

Provider BServer

Servicprovider CClient und Server

Client

InternetInternet

Data transfer using XMLor standard raster formats

Combine different distributed sources

Introduction




Introduction - Thesis

Nobody needs geodata, what we need are problem solutions!

• Therefore we need standards for• geodata descriptions (metadata),• geodata and• access mechanism.

• Standardization is a process• must be find as consensus• established at different levels• and widely accepted!

…like traffic roles in a road network.

Introduction


Standardization Process

• Standard• On demand specification• Derived from products or

industry, main stream, common• Different levels

• Abstraction• International, national, federal,

local • Different information

communities• Geoinformatics• Geodesy• Geology• Geophysics• Biology• Agriculture• Finance economy …

• Norm• On decree• From authorities• State-running

Organisations:• International Standardisation

Organisation (ISO)• Independent organization

• Open Geospatial Consortium (OGC)

• Industry consortium• Committee European Normalization

(CEN)• European Commission

• Deutsche Industrienorm (DIN)• German Organisation





ISO-activities related to spatial information

• ISO = Union of the national norming institutions• TC 211 since November 1994 (TC 204 Car navigation)• 28 Participant-, 33 Observer-member countries and 23

Liaison-members with working groups and project teams• WG 1 Framework and Reference Model• WG 2 Geospatial Data Models and Operators• WG 3 Geospatial Data Administration• WG 4 Geospatial Services• WG 5 Profiles and Functional Standards

• Works on ISO Norm 191xx with various standards• close coupling with OGC since 1997 by TOCG (TC211 –

OGC coordination group).

www.isotc211.org

ISO/TC 211Geographic information/Geomatics



ISO TC 211- goals

• Standardization in the field of digital geographic information.• This work aims to establish a structured set of standards for

information concerning objects or phenomena that are directly orindirectly associated with a location relative to the Earth.

• These standards may specify, for geographic information, methods, tools and services for data management (including definition anddescription), acquiring, processing, analyzing, accessing, presenting and transferring such data in digital/electronic form between different users, systems and locations.

• The work shall link to appropriate standards for information technology and data where possible, and provide a framework for the development of sector-specific applications using geographic data.

Source: http://www.isotc211.org/- Stand 3/2005





ISO 19000 Series - Geographic information/Geomatics

• ISO 6709:1983 Standard representation of latitude, longitude and altitude for geographic point locations

• ISO 19101:2002 Geographic information -- Reference model• ISO/TS 19103:2005 Geographic information -- Conceptual schema

language• ISO 19105:2000 Geographic information -- Conformance and testing• ISO 19106:2004 Geographic information -- Profiles• ISO 19107:2003 Geographic information -- Spatial schema• ISO 19108:2002 Geographic information -- Temporal schema• ISO 19109:2005 Geographic information -- Rules for application schema• ISO 19110:2005 Geographic information -- Methodology for feature

cataloguing• ISO 19111:2003 Geographic information -- Spatial referencing by

coordinates• ISO 19112:2003 Geographic information -- Spatial referencing by

geographic identifiers• ISO 19113:2002 Geographic information -- Quality principles• ISO 19114:2003 Geographic information -- Quality evaluation procedures


Source: http://ioc.unesco.org/oceanteacher/OceanTeacher2/02_InfTchSciCmm/05_ProgAgen&Orgs/ISO/ISO19000.htm


ISO 19000 Series - Geographic information/Geomatics II

• ISO 19115:2003 Geographic information -- Metadata• ISO 19116:2004 Geographic information -- Positioning services• ISO 19117:2005 Geographic information -- Portrayal• ISO 19118:2005 Geographic information -- Encoding• ISO 19119:2005 Geographic information -- Services• ISO/TR 19120:2001 Geographic information -- Functional standards• ISO/TR 19121:2000 Geographic information -- Imagery and gridded data• ISO/TR 19122:2004 Geographic information / Geomatics -- Qualification and

certification of personnel• ISO 19123:2005 Geographic information -- Schema for coverage geometry and

functions• ISO 19125-1:2004 Geographic information -- Simple feature access -- Part 1:

Common architecture• ISO 19125-2:2004 Geographic information -- Simple feature access -- Part 2: SQL

option• ISO/TS 19127:2005 Geographic information -- Geodetic codes and parameters• ISO 19128:2005 Geographic information -- Web map server interface• ISO 19133:2005 Geographic information -- Location-based services -- Tracking and

navigation• ISO 19135:2005 Geographic information -- Procedures for item registration

Source: http://ioc.unesco.org/oceanteacher/OceanTeacher2/02_InfTchSciCmm/05_ProgAgen&Orgs/ISO/ISO19000.htm




Open Geospatial Consortium (OGC)

• Founded 1994, formerly Open GIS Consortium• Non-for-profit-organisation• Integrates 339 members from industry, government and sciences

(GIS-vendors, service providers, IT- and DB-enterprises, data suppliers, universities)

• Different types of memberships• Strategic (9, all US), principal (12, 8 from US), technical (50)

• Specifications based on consensus and public available• Technical Committees - Working Groups - Special Interest Groups

(SIG)• Abstract Open GIS Specification• August 1997: Simple Feature Specification• Since 1999 strong focus on Internet• Since 2001 OpenLS: Location Based Services• …



OGC Interoperability

• “Definition of a technology, which allows application developpersand users to use all kind of geocoded data and geo-functionality or -process being available in the net inside his own environment and individual workflows” (Open GIS Guide).

⇒ Interoperability

Source: www.opengeospatial.org - 3-2005

Standardization ProcessOGC VisionA world in which everyonebenefits from geographic

informationand services made available across

any network, application, or platform.

OGC MissionOur core mission

is to deliver interface

specificationsthat are openly

available for global use.




OGC Abstract Specifications

Topic 1Feature

Geometry

Topic 2 SpatialReferenceSystems

Topic 10Feature

Collections

Topic 16Image Coordinates

Transformation Services

Topic 6The Coverage

Type

Topic 5The Open

GIS FeatureTopic 4 StoredFunctions andInterpolation

Topic 12The Open GIS

Service Architecture

Topic 14Semantics and

Info Communities

Topic 15Image Exploitation

ServicesTopic 7

Earth Imagery

Topic 3LocationalGeometry

Topic 8Relations bet-ween Features

Topic 11Metadata

Topic 9Quality

Topic 13CatalogServices

Allways one abstract specification

G. Joos in Bill/Seuß/Schilcher (2002)



Registered OGC-Products – an extract

Autodesk, Inc. Autodesk MapGuideWMS Extension 6.3 WMS 1.1.1 Server Ricordel, Olivier 2002-07-10

Autodesk LocationLogic XML Web Services 2 OLS 1.0 Server Ricordel, Olivier 2003-12-10

Autodesk MapGuideWMS Extension 6.3 WMS 1.1.1 Client Ricordel, Olivier 2003-07-10

Autodesk MapGuide 6 SFO 1.1 Server Ricordel, Olivier 2002-01-21

AED-SICAD AG SICAD-IS Java Client 6.0 WMS 1.0.0, WMS 1.1.0, WMS 1.1.1 Client Mösbauer, Monika 2003-07-17

SICAD-IS D-HTML Client 6.0 WMS 1.0.0 Client Mösbauer, Monika 2003-07-17

SICAD/Raster - IMS 6.0 WMS 1.1.1, WMS 1.1.0, WMS 1.0.0 Server Mösbauer, Monika 2003-07-17

SICAD-IS HTML Client (HTML 3.2) 6.0 WMS 1.0.0 Client Mösbauer, Monika 2003-07-17

SICAD/open - IMS 6.0 WMS 1.1.1, WMS 1.1.0, WMS 1.0.0 Server Mösbauer, Monika 2003-07-17

SICAD/SD - IMS 6.0 WMS 1.0.0 Server Mösbauer, Monika 2003-07-17

Intergraph Corporation GeoMedia GML 2.1, WMS 1.0.0, WMS 1.1.0, WMS 1.1.1, GML 2.0, WFS 0.0.13, WFS 0.0.14, WFS 1.0.0

GeoMedia Professional WMS 1.1.0, SFS BG 1.1 (compliant), WMS 1.0.0, WFS 1.0.0, WFS 0.0.14, WMS 1.1.1, WFS 0.0.13, GML 2.0

GeoMediaWebMap 05.01 WMS 1.1.0, WMS 1.0.0, WFS(T) 0.0.14, WMS 1.1.1 (compliant), WFS 1.0.0 (compliant), WFS 0.0.14, WFS 0.0.13, GML 2.1, GML 2.0

GeoMediaWeb Map Professional 05.01 SFS BG 1.1 (compliant), WMS 1.1.1 (compliant), WFS 1.0.0 (compliant), GML 2.0, WFS 0.0.13, WFS 0.0.14, WFS(T) 0.0.14, WMS 1.0.0, WMS 1.

GeoMedia Data Server for Oracle Object Model Server (Read/Write) 05.01 SFS BG 1.1 (compliant)

GeoMedia Viewer GML 2.1, WMS 1.0.0, WMS 1.1.0, WMS 1.1.1, GML 2.0, WFS 0.0.13, WFS 0.0.14, WFS 1.0.0

WMS Viewer WMS 1.1.0, WMS 1.0.0, SLD 0.7.2, WMS 1.1.1

SMMS GeoConnect 5.x CAT 1.0

UMN MapServer Project MapServer 4.2 WMS 1.1.0, WMS 1.0.0, WMC 1.0, WFS 1.0.0, SLD 1.0, GML 2.0, Filter 1.0.0, WMS 1.1.1 Server and Client Morissette, Daniel 2004-05-25





ESRI ArcGIS Interoperability Tool Bar Add-on8.3

WMS 1.1.0, WFS 1.0.0, GML 2.1 Client Danko, David

0000-00-00

ArcSDE for Informix 8.1 SFS TF 1.1 (compliant) Server and Client

Danko, David

2001-06-21

ArcExplorer Web WMC 1.0, WMS 1.0.0, WMS 1.1.0, WMS 1.1.1 Client Danko, David

0000-00-00

ArcIMS 4.0, 4.0.1 WMS 1.1.1, WMS 1.1.0, SLD 0.7.2, SLD 1.0 Server and Client

Danko, David

0000-00-00

ArcGIS Server 9.0 WCS 1 Server Danko, David

0000-00-00

ArcGIS 8.1 SFO 1.1 (compliant) Client Danko, David

2001-06-21

ArcIMS Data Delivery Extension 9.0 GML 3.0, GML2.1 2.1.2, WFS 1.0.0 Server Danko, David

0000-00-00

Spatial Database Engine for Informix3.0.2

SFS TF 1.1 (compliant) Client Danko, David

1999-12-23

ArcIMS Metadata server 4.0,4.0.1 CAT 1.0, CAT 1.1.1 Server and Client

Danko, David

0000-00-00

ArcIMS 9.1 Filter 1.0.0, GML 2.1, GML 3.0, GML2.1 2.1.2, SLD 1.0, WFS 1.0.0 Server and Client

Danko, David

0000-00-00

ArcGIS Data Interoperability Extension 9.0

WFS 1.0.0, GML2.1 2.1.2, GML 3.0 Client Danko, David

0000-00-00

Spatial Database Engine for DB2 Datajoiner 3.0.2

SFS TF 1.1 (compliant) Client Danko, David

1999-12-23

ArcIMS 3.0 WMS 1.0.0 Server Danko, David

2000-10-10

ArcIMS 4.0 WFS 0.0.13 Server Danko, David

2002-10-29

ArcIMS Metadata Server 9.0 CAT 1.1.1, CAT 1.0, CAT 2 Server and Client

Danko, David

0000-00-00

ArcIMS 9.0 WMS 1.0.0, WMS 1.1.0, WMS 1.1.1 Server Danko, David

0000-00-00

ArcIMS 4.0 WFS 0.0.14 Server Danko, David

2002-10-29

ArcLocation Solutions OLS 1.0 Server and Client

Danko, David

0000-00-00

Spatial Database Engine for Oracle 3.0.2

SFS NG 1.1 (compliant) Client Danko, David

1999-12-23

ArcIMS 4.0 WMS 1.0.0 Server Danko, David

2002-10-29

ArcSDE SQL Server 9.0 SFS BG 1.1 Server Danko, David

0000-00-00

Arc Explorer 4.0.1 WMS 1.1.0, WMS 1.0.0, WFS 1.0.0, GML 2.1, WMS 1.1.1 Client Danko, David

2003-02-20

GIS Portal Tool Kit 2.0 CAT 1.0, CAT 1.1.1, CAT 2, WCS 1, WFS 1.0, WMC 1.0, WMS 1.0.0, WMS 1.1.0, WMS 1.1.1

Server and Client

Danko, David

2004-11-01

ArcGIS 9.0 WCS 1, WMS 1.1.1 Client Danko, David

0000-00-00

ArcSDE for DB2 8.1 SFS TF 1.1 (compliant) Server and Client

Danko, David

2001-06-21

ArcSDE Oracle 9.0 SFS BG 1.1 Server Danko, David

0000-00-00


Registered OGC-Products – an extract


OGC Web Services

• Distributed data through services interface• Less redundant data• Authoritative• More effective data management• Connect rather than hoard

• Transparent / cooperative• Based on open specifications

• W3C (World Wide Web Consortium), OGC (Open Geospatial Consortium)• Normalizes playing field, independent of:

• Operating System• Programming Languages• Development Environments

• How? - Web Services!• Web Service = any software which makes itself available over the Internet

and uses a standard XML messaging system• Provides more control to application developer• XML makes this happen





OGC Web Service Specifications

• Recent developments with relevance for the market• WMS (Web Map Service 1.3)

• Access to raster maps/imagery (GIF/PNG/JPG)• WFS (Web Feature Service 1.0.0)

• Access to features/vector data (GML)• WCS (Web Coverage Service 1.0.0)

• Access to raster coverages• WCAS (Web Catalogue Service)

• Access to meta data (XML/ISO 19115)• WGS (Web Gazetteer Service)

• Searching based on names• WCTS (Web Coordinate Transformation Service-Draft)

• Transformation between reference systems• WTS (Web Terrain Service-Draft)

• 3D-terrain views• Web Pricing and Ordering Service (Draft)• GML (Geography Markup Language 3.0)

• Base for a distributed, heterogeneous GI-architecture

www.opengeospatial.org - State 3-2005 and A. Poth and J. Fitzke (2002)



Web Services in MapServer

• Defined through metadata elements in mapfile• “ows_*” Metadata applied for alle services

Metadata for a WMS layer in MapServer• "ows_title" "Rivers"• "ows_abstract" "These are rivers"• "ows_keywordlist" "Rivers,world"• "ows_srs" "EPSG:4326"• "ows_metadataurl_type" "FGDC"• "ows_metadataurl_href" "http://localhost/metadata.html"• "ows_metadataurl_format" "text/html"

• “wms_*”, “wfs_*” … for special services

Web M

ap Service




Web Map Service (WMS)

• Provides images of map data defined by a geographic / spatial component

• Provides point based query functionality• Interoperable means of map compositing from n servers• ‘just-in-time’ approach• HTTP based (GET or POST)• Currently version 1.3.0• Operations

• GetCapabilities• GetMap• GetFeatureInfo

• Operation keywords are case-insensitive• Opearation values are case-sensitive• E.g. ReQuEsT=GetCapabilities

Web M

ap Service


Web Browser

Viewer Client

MapServer

MapServer

MapServer

MapServer

inte

rnet

Web Map Servers

http://ceoware2.ccrs.nrcan.gc.ca/cubewerx/cubeserv/cubeserv.cgi?version=1.1.0&service=wms&request=GetMap&bbox=-72.478366,40.108703,-55.746366,50.135369&width=500&height=300&srs=EPSG:4326&layers=L7O_B743:CEOWARE2&format=image/gif&transparent=TRUE&exceptions=application/vnd.ogc.se_inimage&styles=default

http://wms.cits.rncan.gc.ca/cgi-bin/cubeservcubeserv.cgi?version=1.1.0&service=wms&request=GetMap&bbox=-72.478366,40.108703,-55.746366,50.135369&width=500&height=300&srs=EPSG:4326&layers=ROUTE_1:BNDT/NTDB-250K&format=image/gif&transparent=TRUE&exceptions=application/vnd.ogc.se_inimage&styles=default

http://ceoware2.ccrs.nrcan.gc.ca/cubewerx/cubeserv/cubeserv.cgi?version=1.1.0&service=wms&request=GetMap&srs=EPSG:4326&bbox=-80.279475,43.082972,79.281178,43.682405&width=500&height=300&layers=L7O_B743:CEOWARE2&format=image/gif&transparent=TRUE&exceptions=application/vnd.ogc.se_inimage&styles=default

http://wms.cits.rncan.gc.ca/cgi-bin/cubeserv.cgi?version=1.1.0&service=wms&request=GetMap&srs=EPSG:4326&bbox=-80.279475,43.082972,79.281178,43.682405&width=500&height=300&layers=ROUTE_1:BNDT/NTDB-250K&format=image/gif&transparent=TRUE&exceptions=application/vnd.ogc.se_inimage&styles=default

WMS Overlay

Web M

ap Service




WMS GetCapabilitiesW

eb Map Service

• Provides XML of service functionality metadata, and layer metadata• Parameters

• Version (version of specification)• Service (multiple services may exist from this service, e.g. WMS, WFS,

WCS)• Request (GetCapabilities)

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.1.1&service=WMS&request=GetCapabilities


WMS DescribeLayer

Web M

ap Service

• OPTIONAL operation to provide more information about a WMS layer (WFS, etc.)

• Parameters• VERSION• SERVICE• REQUEST• LAYERS

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.1.1&service=WMS&request=DescribeLayer&layers=rivers




WMS GetMap

• Returns graphic image of data based on area of interest, data, etc.• Image, not features, not attributes• Parameters

• VERSION (version of specification)• SERVICE (multiple services may exists from this service, e.g. WMS,

WFS, WCS)• REQUEST (GetMap)• FORMAT (image format to be returned)

• Get this from GetCapabilities info• BBOX (spatial area of interest, i.e. minx,miny,maxx,maxy)• SRS (reference system / projection of bounding box coordinates

• EPSG (http://www.epsg.org/)• Get supported SRSs from GetCapabilities

• Most widely used SRS is EPSG:4326• Lat/long geographic (WGS84)

Web M

ap Service


WMS GetMap II

• Parameters• WIDTH (output image width)• HEIGHT (output image height)• LAYERS (data desired to be visualized)

• Get this from GetCapabilities info• Comma-separated list

• Eg. Layers=elevation,roads,railways,…• First list item is bottom most output layer

• TIME• ISO 8601 formatted timestring• Single point• Frequency• Range• Current

• Not all WMS implementations support TIME

Web M

ap Service




WMS GetMap III

• Parameters• Styles (desired portrayal of data)

• Get this from GetCapabilities info per layer• Comma-separated list

• e.g.. layers=elevation,roads,railways&styles=default,red,blue• Style list MUST align with layer list• Empty list value for non styled layers• e.g. to style ONLY railways layer: layers=elevation,roads,railways&styles=,,blue

• Styles and SLD• SLD enables remote classification and symbolization of data• Overrides server-based styles if request from user• To use in GetMap, SLD document must exist over HTTP, and cited in

GetMap request• &sld=http://localhost/ms_ogc_workshop/sld/rivers.sld• OR &sld_body=<entire_sld_document>• (consider HTTP POST for SLD_BODY)

• More info on SLD later

Web M

ap Service


WMS GetMap IV

Web M

ap Service

• Parameters• TRANSPARENT (whether to make non-opaque data pixels transparent

• Either TRUE or FALSE• Useful for layering data from multiple remote WMS services atop eachother

for map composition• Depends on image format (JPEG is not transparent)• Depends on web browser support• GIF transparency is supported in all browsers• PNG transparency support in newer browsers

• BGCOLOR (optional background color of image)• EXCEPTIONS (how to handle errors)

• Can be caused by:• Server malfunction• Invalid client syntax (missing required values, etc.)

• application/vnd.ogc.se_xml• application/vnd.ogc.se_inimage• application/vnd.ogc.se_blank




WMS GetMap VW

eb Map Service

• Parameters• EXEPTION

• Which one should I use?• application/vnd.ogc.se_inimage

• Useful for easily visualizing errors in your app• Can also be ugly to the end-user / audience

• application/vnd.ogc.se_blank• Returns a blank image• Difficult to recognize what type or error has occurred• application/vnd.ogc.se_xml

• Returns an XML exception document• Difficult to decode if your app is requesting an image type• Choose accordingly


WMS Example

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.1.1&service=WMS&request=GetMap&srs=EPSG:4326&bbox=70,0,130,30&format=image/png&layers=land_shallow_topo_2048,rivers&styles=,&width=500&height=300

Web M

ap Service




WMS GetFeatureInfo

• Performs point-based queries on map data• No ability for complex, expression-like queries

• This is covered the WFS specification• Parameters

• <all GetMap parameters>• REQUEST=GetFeatureInfo instead of GetMap• Pass on ALL GetMap keyword-value pairs as if performing a GetMap

request, can also be used for query maps• X,Y pixel values in image coordinates related to the GetMap params• QUERY_LAYERS (layers to be queried)

• Can be one or multiple layers• INFO_FORMAT

• Return format (MIME type) of feature information• Only the formats given in the capability document are supported

• FEATURE_COUNT• Limitation of the amount of returned features

Web M

ap Service


WMS GetFeatureInfo II

• Parameters• INFO_FORMAT

• Get this from GetCapabilities info• Common formats

• HTML

» difficult to parse• GML.1

» XML-based» Lacks common definition structure between vendor

implementations• See http://127.0.0.1/ms_ogc_workshop/ for examples

Web M

ap Service




Publishing WMS with MapServer

• Through metadata elements in mapfile, “ows_*” or “wms_*” type(see wms-server howto)

Web M

ap Service


WMS related Metadata

In Web Object• "wms_attribution_onlineresource" "http://www.ec.gc.ca/"• "wms_attribution_title" "Data from Environment Canada"• "wms_attribution_logourl_width" "655"• "wms_attribution_logourl_height" "130"• "wms_attribution_logourl_format" "image/png"• "wms_attribution_logourl_href"

"http://mapserver.gis.umn.edu/mum/header_fsa.png"• "wms_feature_info_mime_type" "text/html"In Layer Object• "wms_opaque" "0"• "wms_group_title" "Vectors"• "wms_group_abstract" "Vector layers"• "wms_dataurl_href" "http://localhost/ms_ogc_workshop/data/"• "wms_dataurl_format" "text/html"

Web M

ap Service




Styled Layer Descriptor (SLD)

• “Add-on” specification to OGC:WMS• “SLD-enabled WMS”

• Enables custom styling• Data at the server does not have to change• Client sends SLD XML document for symbolization, etc.

• Either as URL or within BODY of the request• If URL, it MUST be resolvable and accessible by the WMS server

• Additional OGC:WMS operations with OGC:SLD:• GetLegendGraphic• GetStyles• PutStyles

Web M

ap Service


SLD GetLegendGraphic

• Dynamic legend icon for a given layer• Parameters

• VERSION• SERVICE• REQUEST• FORMAT• LAYER• SLD

Web M

ap Service

LegendGraphic




SLD GetStyles and PutStyles

GetStyles• Returns OGC:SLD for a given layer• Parameters

• VERSION• SERVICE• REQUEST• LAYERS

PutStyles• Stores SLD document on WMS server• Not supported by MapServer

Web M

ap Service


SLD with MapServer

• Enabling in MapServer• Not much, really

• MapServer code (CGI) basically exposes and converts CLASS objects to SLD constructs

• Also via PHP MapScript to mapObj or layerObj• See here for SLD examples:

• http://127.0.0.1/ms_ogc_workshop/index.html

Web M

ap Service




Web Feature Service (WFS)

• Feature level access to spatial data• Vector data exchange using Geography Markup Language (GML)• Rich query interface • Transactional capability• Operations

• GetCapabilities• DescribeFeatureType• GetFeature

• Web Feature Service Transactional (WFS-T)• GetFeatureWithLock deliver feature and lock• Transaction operation types (create, update, delete)• LockFeature operation for locking feature only• Security considerations• UMN MapServer supports only basic WFS, no transactions

Web Feature Service


WFS GetCapabilities

Web Feature Service

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.0.0&service=WFS&request=GetCapabilities

• Same idea as OGC:WMS GetCapabilities• Parameters

• VERSION• SERVICE• REQUEST




WFS DescribeFeatureType

• Provides an outline of the structure of a feature type (fields, etc.)• Analogous to SQL describe <table> command• Parameters

• VERSION• SERVICE• REQUEST• TYPENAME

Web Feature Service

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.0.0&service=WFS&request=DescribeFeatureType&typename=rivers


WFS GetFeature

• Give me real vector data!• Parameters

• VERSION• SERVICE

• REQUEST• TYPENAME

• FILTER (optional)• BBOX (can also be done through FILTER)

Web Feature Service

Filterencoding (FE):Filter=<Filter>

<PropertyIsEqualTo><PropertyName>NAME</PropertyName><Literal>Digby</Literal>

</PropertyIsEqualTo></Filter>




WFS enabling in MapServer

• Through metadata elements in mapfile, “ows_*” or “wfs_*” type(see wfs-server howto)

• Layers must contain “DUMP TRUE”• Metadata in WEB Object

• "wfs_namespace_uri" "http://localhost/ms_ogc_workshop"• sets namespace URI when performing a DescribeFeatureType or GetFeature in

the root element of the XML response• "wfs_namespace_prefix" "ms_ogc_workshop"

• sets the XML namespace prefix to be used when defining types for data in this mapfile

• Metadata in Layer Object• "wfs_metadataurl_format" "TXT"

• Sets /WFS_Capabilities/FeatureTypeList/FeatureType[*]/MetadataURL/@format• "gml_include_items" "all"

• specify which fields to include when returning queries

Web Feature Service


WFS with MapServer Example

Web Feature Service




Geography Markup Language (GML)W

eb Feature Service

• Text-based, portable data format• Self-describing, XML• GML schemas define geospatial objects for you• YOU define what’s specific to your data• attributes, etc.

• Primitives to build application specific schemas• Feature• Geometry• Coordinate Reference System• Time • Dynamic feature • Coverage (including geographic images) • Unit of measure • Map presentation styling rules


GML Schema and Instance

Web Feature Service




Serving GML with MapServer

• GML usually comes from a OGC:WFS• MapServer can also serve up static files

• OGR supports GML2• GML3 includes some sophisticated data modelling capabilities

not inherent in OGR• Certain structure required for OGR to recognize content model• Dataset/record type hierarchy must be considered

• You can serve up GML:• From GML documents you made yourself• From GML documents you copied from elsewhere• By doing nothing; OGC:WFS offers GML already

• Any GML parser can read your data!!

Web Feature Service


• Making it happen• CONNECTIONTYPE OGR• CONNECTION “/path/to/gml/document”• The rest is like any other LAYER object definition in the mapfile

• OGR processing• Creates and caches *.gfs overview type file when first reading

the data• Quicker for subsequent data scans

Serving GML with MapServer

Web Feature Service




Serving GML with MapServer II

• MapServer now supports GML3!• via WFS supports both GML2 and GML3• Same as serving GML2 for WFS• WFS requests should have:

• DescribeFeatureType “outputFormat=XMLSCHEMA”• DescribeFeatureType “outputFormat=SFE_XMLSCHEMA”• GetFeature “outputFormat=GML3”• GetFeature “outputFormat=GML2”

• Check out mums.gml for an example in ms_ogc_workshop• Check out mums.xsd for the XML Schema definition• MapServer doesn’t necessarily use the .xsd• Good practice nonetheless for validating XML parsers

Web Feature Service


GML output by MapServer

• GML2 or GML3 specified in the OUTPUTFOMAT• GML2 request output

http://www2.dmsolutions.ca/cgi-bin/mswfs_gmap?SERVICE=WFS&VERSION=1.0.0&REQUEST=getfeature&TYPENAME=park&maxfeatures=1&OUTPUTFORMAT=gml2

• GML3 request outputhttp://www2.dmsolutions.ca/cgi-bin/mswfs_gmap?SERVICE=WFS&VERSION=1.0.0&REQUEST=getfeature&TYPENAME=park&maxfeatures=1&OUTPUTFORMAT=gml3

Web Feature Service




WFS and community schemas

• The WFS standard mandates the use of GML as the default (and only required) response format• but GML cannot be used directly: an application schema must first be

defined• community schemas may be defined not using GML

• The usual approach in WFS configuration is that a GML application schema is defined ad hoc to match the internal storage schema of the data• the user of the WFS must process and be able to interpret the schema

and the data

• Most WFS software only supports simple features• one geometry property per feature• no relationships to other features

Web Feature Service


OGC:Filter Encoding (FE)

• “Add on” specification to OGC:WFS• Custom XML query language• SQL in XML, almost• Spatial and aspatial query capabilities

• Logical• Spatial• Comparative

• SQL: SELECT * FROM roads WHERE roadtype=1• OGC Filter: <Filter>

<PropertyIsEqualTo><PropertyName>roadtype</PropertyName><Literal>1</Literal>

</PropertyIsEqualTo></Filter>

Web Feature Service




OGC:Filter Encoding logical operationsW

eb Feature Service

<Filter><And>

<PropertyIsEqualTo><PropertyName>NAME</PropertyName><Literal>Japura</Literal>

</PropertyIsEqualTo><PropertyIsEqualTo>

<PropertyName>SYSTEM</PropertyName><Literal>Amazon</Literal>

</PropertyIsEqualTo></And>

</Filter>Examples at: http://mapserver.gis.umn.edu/docs/howto/filterencoding


OGC:Filter Encoding spatial capabilities

Web Feature Service

<Filter><DWithin>

<PropertyName>Geometry</PropertyName><gml:Point>

<gml:coordinates>105.1207,21.5325

</gml:coordinates></gml:Point><Distance units='m'>1000</Distance>

</DWithin></Filter>




Web Coverage Service (WCS)

• The raster equivalent to OGC:WFS• In version 1.1.0 features organized in Grid• Provides “real” raster data

• DEM• GeoTIFF

• Operations• GetCapabilities• DescribeCoverage• GetCoverage

• Simple query function with spatial and temporal filter capabilities

Web C

overage Service


WCS GetCapabilities

• Same idea as OGC:WMS GetCapabilities• Parameters

• VERSION• SERVICE• REQUEST

Web C

overage Service

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.0.0&service=WCS&request=GetCapabilities




WCS DescribeCoverage

• Provides an outline of the structure of a coverage• bands• resolution

• Parameters• VERSION• SERVICE• REQUEST• COVERAGE

http://127.0.0.1/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.0.0&service=WCS&request=DescribeCoverage&coverage=toronto

Web C

overage Service


WCS GetCoverage

Web C

overage Service

• Deliver grid data• Parameters

• VERSION• SERVICE• REQUEST• COVERAGE• CRS• FORMAT• BBOX• RESX, RESY

http://localhost/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop/service/config.map&version=1.0.0&service=WCS&request=GetCoverage&coverage=toronto&crs=EPSG:26917&resx=500&resy=500&format=GEOTIFF_RGB




Web Coverage Service with MapServer

• Through metadata elements in mapfile, “ows_*” or “wcs_*” type• Layers must contain “DUMP TRUE”

• see wcs-server howto• Metadata in WEB Object

• "wcs_label" "Sample OWS for MapServer OGC Web Services Workshop"

• sets: /WCS_Capabilities/Service/label• "wcs_description" "Sample OWS for MapServer OGC Web Services

Workshop. Enjoy!"• sets: /WCS_Capabilities/Service/description

• "wcs_metadatalink_href" http://localhost/ms_ogc_workshop/index.html• sets: /WCS_Capabilities/Service/metadataLink/@xlink:href

Web C

overage Service


WCS Metadata in layer object

• "wcs_label" "Landsat 5 TM - Toronto"• "wcs_resolution" "500 500"

• x and y resolution of the data how many bands is the image?• "wcs_bandcount" "3"• "wcs_formats" "GEOTIFF_RGB"

• what formats are supported?• “wcs_nativeformat" "raw binary"

• what is the native format of the data?• "wcs_description" "Toronto Landsat 5 TM"

• abstract text• "wcs_metadatalink_href" "http://geogra....di.gc.ca/clf/en?&entryId=4373"

• url• “wcs_keywordlist" "landsat,toronto“

• Keywords• "wcs_rangeset_axes" "bands"

• rangeset type• "wcs_rangeset_name" "Landsat 5 TM Bands"

• rangeset name • "wcs_rangeset_label" "Bands"

• rangeset title • "wcs_rangeset_description" "Bands for Landsat 5 TM“

• rangeset description

Web C

overage Service




Web Map Context (WMC)

• Map context stored in documents• Saves web mapping application state

• remote WMS layer pointers• Like “project” files in common desktop GIS• XML-based• Check out: mapcontext howto• MapServer deliver WMC using CGI

• parameter request=GetContext• Default OFF

• phpMapScript metods for WMC handling• saveMapContext (saves a WMC from a MapObject)• loadMapContext (load a WMC and use in a MapObject)

• Examples and mapfiles with WMC requests:• http://127.0.0.1/ms_ogc_workshop/context/demo.map• http://127.0.0.1/ms_ogc_workshop/index.html

Web M

ap Context D

ocument


Web Map Context in mapfile

• Metadata in Layer object• "wms_getcontext_enabled" "1“

• if this value is set to 1, you can convert a mapfile to an OGC:WMC via URL• "wms_context_fid" "ms_ogc_workshop"

• sets: /ViewContext/@id• "wms_context_version" "1.0.0"

• sets: /ViewContext/@version

Web M

ap Context D

ocument




Web Map Context Document Example

http://localhost/cgi-bin/mapserv.exe?map=/ms4w/apps/ms_ogc_workshop /context/demo.map&request=GetContext W

eb Map C

ontext Docum

ent


Web Map Context apply with MapServer

• Two ways to use WMC with MapServer• Local map context document

http://localhost/mapserver.cgi?MODE=map&MAP=/path/to/mapfile.map&CONTEXT=/path/to/contextfile.xml&LAYERS=layer_name1,layers_name2

• Linking to a remote map context document via URLhttp://localhost/mapserver.cgi?MODE=map&MAP=/path/to/mapfile.map&CONTEXT=http://URL/path/to/contextfile.xml&LAYERS=layers_name1,layer_name2

Web M

ap Context D

ocument




Other OGC Service and specification activities

• Metadata• Catalogue Service Web (CS-W)• Gazetteer Service

• Sensor Web Enablement (SWE)• Sensor Observation Service (SOS)

• Processing• Web Coordinate Transformation Service (WCTS)• Web Processing Service (WPS)

• Authentication and Authorization• Web Authentication Service (WAS)• Web Security Service (WSS)

• Geospatial Linking• Geospatially linked Data Access Service• Geolinking Service

Other W

eb Services


Web Processing Service (WPS)

Parameter• getCapabilities

• Describes name, opterations, versioninformation• describeProcess

• Input Parameter and Format and Output• execute

• Running the process• Common aspects specified in OGC Web Services Common

Implementation

Other W

eb Services




WPS GetCapabilities

http://foo.bar/foo?service=WPS&version=0.3.0&request=GetCapabilities

• Responsed service metadata (Sections)• ServiceIdentification• ServiceProvider• OperationsMetadata• mandatory version• optional updateSequence

Other W

eb Services


WPS ProcessOffering

Other W

eb Services




WPS DescribeProcess

This description can be used to build an automatic user interface to capture the parameters values used to execute a process instance.

Get:

Post:

Other W

eb Services

http://foo.bar/foo?service=WPS&request= DescribeProcess&Version=0.3.0&Identifier=substraction,addition


WPS DescribeProcess response

• Response the capabilities and additional a descriptions of the input and output parameter

• The parameter can be described in different ways• <Reference> URL linking to a suitable GML Schema• <LiteralValue> according to <AllowedValues>, <DefaultValue> and

<SupportedUoms>• <ComplexValue> according to a certain format• <BoundingBox> enclosing rectangle

Other W

eb Services




WPS DescribeProcess response II

Continuation next slide

Other W

eb Services


WPS DescribeProcess response III

Other W

eb Services




WPS Execute

• Calling with parameters gained from DescribeProcess operation• Response one or more resources, must be web accessable• Execute must response a state element, describes web resources:

• for querying the state during the process is running• where and how to get the results of the process

• Supported state values• PROCESS_ACCEPTED

PROCESS_STARTED• PROCESS_SUCCESS• PROCESS_FAILED

• Request example with Get:

Other W

eb Services


WPS Execute exeptions

• Possible exeptions with execute queries• OperationNotSupported• MissingParameterValue• InvalidParameterValue• NoApplicableCode

• Returned formated in XML

Other W

eb Services




Web Security Service (WSS) von 52 North

• Gateway to access protected OGC Web Services (OWS)• Secure data transfer and operations between Client und OWS• Require a pre-authentication

• Ticket from Web Authentication Service (WAS)• Parse the query for access rights• WSS forwarding the query to the OWS and deliver the response back to the

user• Based on interceptors for different permission aspects• Currently tree interceptors for WMS supported by 52 North:

• Access protection for layers in requests• GetCapabilities• GetMap• GetFeatureInfo.

WAS WSS WMSClientRequest

Response

Other W

eb Services


Internet and Desktop GIS interaction with OWS

Other W

eb Services

Source: http://udig.refractions.net/docs/udig-summary.pdf




Spatial data infrastructure (SDI)

• Origin: 1992 UN Conference in Rio• Geoinformation is necessary for all kinds of decisions • Background information for the evaluation and introduction of national

spatial data infrastructures• SDI (Spatial Data Infrastructure)

• Concept of a reliable and supporting environment• Allocation of spatial data and attributes, sufficient documentation (meta

data), tools for searching, visualisation and analysis of data, methods for access on data

• Definition:• A base collection of technologies, policies and institutional

arrangements that facilitate the availability of and access to spatial data. The SDI provides a basis for spatial data discovery, evaluation, and application for users and providers within all levels of government, the commercial sector, the non-profit sector, academia and by citizens in general (Nebert, 2001, SDI Cookbook).

Spatial Data Infrastructure


Spatial data infrastructure

• Comparable to other types of infrastructure such as road network. SDI is a combination of

• technical,• organisational and• Jurisdical

regulations concerning spatial information resources, where providers of geodata services and users of such services are somehow cooperating.

• SDI is the prerequisite to create added values for many users inadministration as well as in commercial and non-commercial fields.

=> GSDI - Global Spatial Data Infrastructure=> NSDI - National Spatial Data Infrastructure=> LSDI - Local Spatial Data Infrastructure

www.geoinformatik.uni-rostock.de – Geoinformatik-Lexikon





National spatial data infrastructures

• In USA• National Spatial Data Infrastructure (NSDI) initiative started from Bill

Clinton 1994, beard by the Federal Geospatial Data Committee (FGDC)• In Germany

• Arbeitsgemeinschaft der Vermessungsverwaltungen (AdV)• Interministery board for spatial information (IMAGI)

• In Switzerland• Strategy for geoinformation on national level• Signed by Bundesrat in July 2001• A major statement:

“Because of their relevance geoinformation are an important elementin a national infrastructure, comparable to the road- orcommunication network.“



Kodex Höhe Index ....112 344 2334 fe33113 24 2234 fe22114 23432 2235 fr55115 23343 2267 fs22116 243 2334 fs11

GDI-DE – an example

GeoPortal.Bund®

Entry point GDI-DE - Data - Services - PortalGeo-Search engine: GeoMIS.Bund®

Access to NGDB, data integration, mapping,ordering and delivery

GeoPortal.Bund®

Entry point GDI-DE - Data - Services - PortalGeo-Search engine: GeoMIS.Bund®

Access to NGDB, data integration, mapping,ordering and delivery

GDI-DE = {NGDB, Network, Services, Standards}GDI-DE = {NGDB, Network, Services, Standards}

National geodatabaseNGDB = {Geobase data, branch data, meta data}National geodatabaseNGDB = {Geobase data, branch data, meta data}





Levels of spatial data infrastructures

Application of standardised architectures/interfaces, interoperability of heterogeneous applications

Technology level

Integration and setup of transparent offers, standardising data/meta data

Data level

Definition of access- and usage conditions, price models etc., SDI-guidelines integrated in the statutes of organisations and administrative units/disciplines

Legal level

Target orientated linkage of administration, enterprises, science and citizens under feasible frame conditions

Organisational level

ContentLevel



Current developments - tomorrow

• Mobile sensor networks for early detection of natural danger andterroristic threat

• Electronic monitoring/inspection/supervising of critical infrastructure• Positioning, alarming and specific evacuation of population under

concerns• Support of the coordinated command of various operation forces

using a GIS-based operation control unit





Current research topics - Embedding

• Ontologies, semantic web, common language• Real-time sensors, Geosensor-Networks• Real-time decisions, decision support systems• Ubiqitous computing