OGC Web Services

1
OGC Web Services
Kai Lin San Diego Supercomputer
Center klin_at_sdsc.edu
2
OGC Web Services

• OGC Specifications
• Based on HTTP Protocol (GET/ POST)
• XML as standard encoding (W3C)
• Related to geospatial information
• Some of main OGC services
• Web Map Service (WMS)
• Web Feature Service (WFS)
• Web Coverage Service (WCS)
• Catalogue Service for the Web (CSW)
• Not SOAP. REST?

3
Web Map Service (WMS)

• Requests for images of map data
• Point based query functionality
• Main operations
• GetCapabilities
• Metadata about the types/operations the WMS
  supports
• GetMap
• Map of the requested data
• GetFeatureInfo
• Feature information about a particular point
  within a map
• Open source implementations
• UMN Map Server
• GeoServer

4
Web Feature Service (WFS)

• Requests for spatial features
• Return vector data (in GML)
• Rich query interface
• Main operations
• GetCapabilities
• Metadata about the types/operations the WFS
  supports
• DescribeFeatureType
• A list of features and associated attributes
• GetFeature
• Features by spatial querying and filtering
• Open source implementations
• GeoServer
• Deegree

5
Web Coverage Service (WCS)

• Requests for raw (typically gridded) data
• Return in well known binary formats
• Main operations
• GetCapabilities
• Metadata about the types/operations the WCS
  supports
• DescribeCoverage
• Structural information about one or more
  coverages
• GetCoverage
• Coverage data by spatial querying and filtering
• Open source implementations
• GeoServer
• Deegree

6
Catalogue Service for the Web (CSW)

• Standard API for manipulating metadata records
• creating, updating, deleting for resource
  providers
• querying metadata records for resource users
• Profiles (Information Model)
• FGDC
• ISO19119 / ISO19115
• OASIS eBussiness Registry Information Model
  (ebRIM, preferred)
• Request formats XML or name-value pairs
• Query language
• Filter Encoding Specification (used in WFS)
• Common Query Language (CQL)
• Others defined in profiles
• Response in XML
• Open source implementations GeoNetwork, Deegree

7
A Typical CSW Use Case
Client
Description (Metadata)
Resource
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CSW Operations

• GetCapabilities
• Metadata about the types/operations the CSW
  supports
• DescribeRecord
• Schema description of the CSW Information Model
• GetDomain
• Runtime value space for parameters used in API
• GetRecords
• Metadata records with possibility of filtering
  (spatial, temporal, keywords conditions, etc.)
• GetRecordByID
• Metadata records with the specified ID
• Transaction
• Create, update and delete metadata records
• Harvest
• Retrieve metadata from other catalogue services
• Supporting periodic retrieving

9
What You Can Query

• Core Queryables
• Subject the topic of the resource
• Title the name of the resource
• Abstract a summary of the resource
• AnyText for full text search
• Format physical manifestation
• Identifier unique reference to the resource
• Modified data the resource created or updated
• Type genre of the resource
• BoundingBox a bounding box for interested area
• CRS coordinate system
• Association relation with other resources

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What CSW Response for a Query

• Response Returnables
• Title correspondent to the query attribute
  Title
• Creator
• Subject correspondent to the query attribute
  Subject
• Description correspondent to the query
  attribute Abstract
• Publisher
• Contributor
• Date correspondent to the query attribute
  Modified
• Type correspondent to the query attribute
  Type
• Format correspondent to the query attribute
  Format
• Identifier correspondent to the query
  attribute Identifier
• Language
• Relation correspondent to the query attribute
  Association
• Coverage correspondent to the query attribute
  BoundingBox
• Rights

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CSW Response Levels
Full Level
Creator Publisher
Contributor Language Rights
Summary Level
Subject Format
Description Date Coverage
Relation
Brief Level
Identifier Title
Type
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Example Request of CSW GetRecords
lt?xml version"1.0" encoding"UTF-8"?gt ltGetRecords
service"CSW" version"2.0.2" maxRecords"1000"
outputSchema"http//www.op
engis.net/cat/csw/2.0.2" outputFormat"application
/xml"gt ltQuery typeNamescswRecordgt
ltElementSetNamegtbrieflt/ElementSetNamegt
ltConstraint version"1.2.0gt
ltogcFiltergt ltogcAndgt
ltogcPropertyIsLike escape"" singleChar"_"
wildCard""gt
ltogcPropertyNamegt/Record/AnyTextlt/ogcPropertyNam
egt ltogcLiteralgtYour-Search-T
ermlt/ogcLiteralgt
lt/ogcPropertyIsLikegt
ltogcT_Duringgt
ltogcPropertyNamegt/Record/dctmodifiedlt/ogcProper
tyNamegt ltgmlTimePeriodgt
ltgmlbegingt2007-01-01lt/gmlbegingt
ltgmlendgt2007-12-31lt/gmlendgt
ltgmlTimePeriodgt
lt/ogcT_Duringgt ltogcOrgt
ltogcPropertyIsEqualTogt
ltogcPropertyNamegt/Record/dctypelt/ogcPropert
yNamegt ltogcLiteralgturncsw-
ObjectTypeFeatureTypelt/ogcLiteralgt
lt/ogcPropertyIsEqualTogt
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Example Request of CSW GetRecords (cont.)
ltogcPropertyIsEqualTogt
ltogcPropertyNamegt/Record/dcTypelt/ogcProperty
Namegt ltogcLiteralgturncsw-Ob
jectTypeWMS_Layerlt/ogcLiteralgt
lt/ogcPropertyIsEqualTogt
lt/ogcOrgt ltogcclassifiedAs
scope"broad"gt
ltogcTypeNamegtRecordlt/ogcTypeNamegt
ltogcSchemegturngcmdlt/ogcSchemegt
ltogcNodegturngcmdoceansseafloortopograph
ylt/ogcNodegt lt/ogcclassifiedAsgt
ltogcContainsgt
ltogcPropertyNamegt/Record/owsBoundingBoxlt/ogcPro
pertyNamegt ltgmlEnvelope
srsName"EPSG4326"gt
ltgmllowerCornergt-80,30lt/gmllowerCornergt
ltgmlupperCornergt-70,40lt/gmlupperCor
nergt lt/gmlEnvelopegt
lt/ogcContainsgt lt/ogcAndgt
lt/ogcFiltergt lt/Constraintgt
lt/Querygt lt/GetRecordsgt
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Response of CSW GetRecordById
lt?xml version"1.0" encoding"ISO-8859-1"?gt
ltRecord xmlns"http//www.opengis.net/cat/csw/2
.0.2" xmlnsdc"http//purl.org/dc/ele
ments/1.1/" xmlnsdct"http//purl.org/dc/
terms/" xmlnsows"http//www.opengis.net/
ows" xmlnsxsi"http//www.w3.org/2001/XML
Schema-instance" xsischemaLocation"http
//www.opengis.net/cat/csw/2.0.2
../../../csw/2.0.2/record.xsd"gt
ltdcidentifiergt00180e67-b7cf-40a3-861d-b3a09337b19
5lt/dcidentifiergt ltdctitlegtImage2000
Product 1 (at1) Multispectrallt/dctitlegt
ltdctmodifiedgt2004-10-04 000000lt/dctmodifiedgt
ltdctabstractgtIMAGE2000 product 1
individual orthorectified scenes. IMAGE2000 was
produced from ETM Landsat 7 satellite data and
provides a consistent European coverage of
individual orthorectified scenes in national map
projection systems.lt/dctabstractgt (to
be continued)
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Response of CSW GetRecordById (Cont.)
ltdctypegtdatasetlt/dctypegt
ltdcsubjectgtimagerylt/dcsubjectgt
ltdcsubjectgtbaseMapslt/dcsubjectgt
ltdcsubjectgtearthCoverlt/dcsubjectgt
ltdcformatgtBILlt/dcformatgt
ltdccreatorgtVanda Limalt/dccreatorgt
ltdclanguagegtenlt/dclanguagegt
ltowsWGS84BoundingBoxgt
ltowsLowerCornergt14.05 46.46lt/owsLowerCornergt
ltowsUpperCornergt17.24 48.42lt/owsUpperCor
nergt lt/owsWGS84BoundingBoxgt lt/Recordgt
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ebRIM

• Provides a metamodel for describing metadata
• Expressed in XML
• Manage associations among many aspects
• Dataset descriptions
• Service interface descriptions
• Coordinate reference systems
• Units of Measure
• Application schemas, feature types
• Map styles and symbol libraries
• Access control policies
• Sensor description
• Ontological descriptions
• Digital rights
• Organizations and Projects

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More Queryables by ebRIM

• Queryables
• Time period of data validity
• Time period of collection
• Phenomenon represented
• Geographic Extent
• Topic categories / ISO terms
• Creator
• Organization
• Scale / resolution
• Metalevel
• Classification
• Processed state

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Question?
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WFS GetCapabilities
lt?xml version"1.0" ?gt ltGetCapabilities
service"WFS version"1.0.0"
xmlns"http//www.opengis.net/wfs" /gt
ltWFS_Capabilities xmlns"http//www.opengis.net/wf
s" version"1.0.0" xmlnsogc"http//www.ope
ngis.net/ogc" xmlnsmyns"http//www.example.
com/myns"gt ltServicegt ltNamegt Oracle WFS
lt/Namegt ltTitlegt Oracle Web Feature Service
lt/Titlegt ltAbstractgt Web Feature Service
maintained by Oracle lt/Abstractgt
ltOnlineResourcegthttp//localhost8888/wfsservletlt/
OnlineResourcegt lt/Servicegt ltCapabilitygt
ltRequestgt ltGetCapabilitiesgt .
lt/GetCapabilitiesgt .
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WFS GetCapabilities (Cont.)
ltFeatureTypeListgt ltOperationsgt
ltInsert/gt ltUpdate/gt ltDelete/gt
ltQuery/gt ltLock/gt lt/Operationsgt
ltFeatureType xmlnsmyns"http//www.example.com/my
ns"gt ltNamegt mynsCOLAlt/Namegt
ltTitlegt LIST OF COLA MARKETS lt/Titlegt
ltSRSgt SDO8307lt/SRSgt lt/FeatureTypegt
lt/FeatureTypeListgt lt/WFS_Capabilitiesgt

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WFS DescribeFeatureType
lt?xml version"1.0" ?gt ltwfsDescribeFeatureType
service"WFS version"1.0.0"
xmlnswfs"http//www.opengis.net/wfs"
xmlnsmyns"http//www.example.com/myns"
xmlnsxsi"http//www.w3.org/2001/XMLSchema-instan
ce" xmlnsxsd"http//www.w3.org/2001/XMLSchema
" xsischemaLocation"http//www.opengis.net/wf
s ../wfs/1.0.0/WFS-basic.xsd"gt
ltwfsTypeNamegtmynsCOLAlt/wfsTypeNamegt lt/wfsDescr
ibeFeatureTypegt
ltxsdschema targetNamespace"http//www.example.co
m/myns" xmlnswfs"http//www.opengis.ne
t/wfs" xmlnsmyns"http//www.example.com/myns"
xmlnsgml"http//www.opengis.net/gml"
elementFormDefault"qualified" version"1.0.0"
xmlnsxsd"http//www.w3.org/2001/XMLSchema
"gt ltxsdimport namespace"http//www.opengis.ne
t/gml" schemaLocation"http//localhos
t8888/examples/servlets/xsds/feature.xsd"/gt
ltxsdelement name"COLA" type"mynsCOLAType"
substitutionGroup"gml_Feature"/gt
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WFS DescribeFeatureType (Cont.)
ltxsdcomplexType name"COLAType"gt
ltxsdcomplexContentgt ltxsdextension
base"gmlAbstractFeatureType"gt
ltxsdsequencegt ltxsdelement
name"MKT_ID" type"xsddouble"/gt
ltxsdelement name"NAME" nillable"true"gt
ltxsdsimpleTypegt
ltxsdrestriction base"xsdstring"gt
ltxsdmaxLength value"32"/gt
lt/xsdrestrictiongt
lt/xsdsimpleTypegt lt/xsdelementgt
ltxsdelement name"SHAPE"
type"gmlPolygonMemberType" nillable"true"/gt
lt/xsdsequencegt
ltxsdattribute name"fid" type"xsddouble"/gt
lt/xsdextensiongt lt/xsdcomplexContentgt
lt/xsdcomplexTypegt lt/xsdschemagt
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WFS GetFeature Request
lt?xml version"1.0" ?gt ltwfsGetFeature
service"WFS version"1.0.0 xmlnswfs"http//ww
w.opengis.net/wfs xmlnsogchttp//www.opengis.ne
t/ogc xmlnsmynshttp//www.example.com/myns
xmlnsxsihttp//www.w3.org/2001/XMLSchema-instanc
e xsischemaLocation"http//www.opengis.n
et/wfs ../wfs/1.0.0/WFS-basic.xsd"gt ltwfsQuery
typeName"mynsCOLA"gt ltogcPropertyNamegtmyns
MKT_IDlt/ogcPropertyNamegt
ltogcPropertyNamegtmynsNAMElt/ogcPropertyNamegt
ltogcPropertyNamegtmynsSHAPElt/ogcPropertyNamegt
ltogcFiltergt ltogcAndgt
ltogcAndgt ltogcPropertyIsGreater
Thangt ltogcPropertyNamegtmy
nsCOLA/mynsMKT_IDlt/ogcPropertyNamegtltogcLiteral
gt 2 lt/ogcLiteralgt
lt/ogcPropertyIsGreaterThangt
ltogcPropertyIsEqualTogt
ltogcPropertyNamegtmynsCOLA/mynsNAMElt/ogcPropert
yNamegtltogcLiteralgtcola_clt/ogcLiteralgt
lt/ogcPropertyIsEqualTogt
lt/ogcAndgt ltogcOrgt
ltogcPropertyIsEqualTogt
ltogcPropertyNamegtmynsCOLA/mynsMKT_IDlt/ogcPrope
rtyNamegtltogcLiteralgt3lt/ogcLiteralgt
lt/ogcPropertyIsEqualTogt
ltogcPropertyIsEqualTogt
ltogcPropertyNamegtmynsCOLA/mynsNAMElt/ogcPropert
yNamegtltogcLiteralgtcola_dlt/ogcLiteralgt
lt/ogcPropertyIsEqualTogt
lt/ogcOrgt lt/ogcAndgt
lt/ogcFiltergt lt/wfsQuerygt lt/wfsGetFeaturegt
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WFS GetFeature Response
lt?xml version '1.0' encoding
'UTF-8'?gt ltwfsFeatureCollection
xsischemaLocation"http//www.example.com/myns
http//localhost8888/wfsservlet?featureTy
peId1 http//www.opengis.net/wfs
../wfs/1.0.0/WFS-basic.xsd"
xmlnswfs"http//www.opengis.net/wfs"
xmlnsxsi"http//www.w3.org/2001/XMLSchema-instan
ce"gt ltgmlboundedBy xmlnsgml"http//www.openg
is.net/gml"gt ltgmlBox srsName"SDO8307"gt
ltgmlcoordinatesgt3.0,3.0
6.0,5.0lt/gmlcoordinatesgt lt/gmlBoxgt
lt/gmlboundedBygt ltgmlfeatureMember
xmlnsgml"http//www.opengis.net/gml"gt
ltmynsCOLA fid"3" xmlnsmyns"http//www.example.
com/myns"gt ltmynsMKT_IDgt3lt/mynsMKT_IDgt
ltmynsNAMEgtcola_clt/mynsNAMEgt
ltmynsSHAPEgt ltgmlPolygon
srsName"SDO8307" xmlnsgml"http//www.opengis.n
et/gml"gt ltgmlouterBoundaryIsgt
ltgmlLinearRinggt
ltgmlcoordinates decimal"." cs"," ts"
"gt3.0,3.0 6.0,3.0 6.0,5.0 4.0,5.0 3.0,3.0
lt/gmlcoordinatesgt
lt/gmlLinearRinggt
lt/gmlouterBoundaryIsgt
lt/gmlPolygongt lt/mynsSHAPEgt
lt/mynsCOLAgt lt/gmlfeatureMembergt lt/wfsFeature
Collectiongt