Web Map Service
The Maxar Web Map Service (WMS) is an interoperable, distributed Web Mapping system which defines a set of functions that clients may use to achieve WMS capabilities. Any client making requests that conform to the OGC WMS specification can interact with the WMS server.
A simple and typical example of the structure of a Web Mapping application is a web-based client-server architecture.
Typical Structure of a WMS Application
In a Web Mapping scenario, the client application requests information from the Web Map Server. The Map Server retrieves the appropriate layers of geo-feature data from the database for the specified spatial domain and generates a Map, which is a simple graphic image (i.e. GIF or PNG) that can be viewed directly in a graphical web browser or other pictorial software. The client and Web Map Server interact using Hypertext Transfer Protocol Secure (HTTPS).
WMS Client-Server Architecture
The following architecture depicts a sample integration of WMS client and server applications. Client Viewer is a series of HTML pages running inside a web browser that can interact with the WMS server via client application through HTTP calls. The WMS client manages the interactions with WMS interfaces through HTTPS requests and dynamically generates HTML that can run in a web browser.
The WMS server accepts requests from the WMS client and viewer client in the form of HTTP URL strings, and returns results encoded as XML, GIF, GML, and so on. The database stores geo-feature data that can be accessed and utilized by the WMS server to generate GML documents or draw Maps.
Sample WMS Client Server Application
WMS Service Details
The Maxar WMS supports OGC WMS specification version 1.1.1. The Maxar WMS supports KVP request encoding only; no Simple Object Access Protocol (SOAP) or other protocols are supported. The Maxar WMS provides raster imagery data at multiple resolutions in various formats for use in GIS applications that support the WMS standard.
The Maxar WMS supports the following operations:
- GetCapabilities The GetCapabilities request is used to obtain information about the supported Map layers, including various imagery layers and metadata layers.
- GetMap The GetMap request is used to retrieve Map images of the layers contained in the Online Catalogs.
- GetFeatureInfo The GetFeatureInfo request is used to obtain metadata (information) about the Features displayed in Map images retrieved via GetMap requests.
- GetLegendGraphic The GetLegendGraphic request is used to obtain information about the display styling of the Map layers, specifically the metadata layers.
The Maxar WMS does NOT support the following optional capabilities:
- DescribeLayer operation
- GetStyles operation
- PutStyles operation
As stated above, the Maxar WMS supports Map layers of both imagery and imagery metadata. The data for these layers is supplied in the following way:
- When metadata layers are requested at Map scales smaller than approximately 1:230,000, an imagery bounding box is returned.
- When a Map scale larger than approximately 1:230,000 is requested, only an image date is returned.
- When imagery layers are requested at Map scales smaller than approximately 1:200,000 no imagery is returned.
- At Map scales larger than approximately 1:200,000, Map images are returned.
Integration Procedure
A WMS client application is a program that communicates with the WMS server using the three functions GetCapabilities, GetMap, and GetFeatureInfo, as noted earlier. More specifically, in a typical WMS client/server interaction, the following steps can be followed:
Step 1
The client must first request GetCapabilities from the WMS server in order to determine what the Map server can do and what Maps the Map server can provide.
| https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&service=WMS&request=GetCapabilities&version=1.1.1 Note: Replace <CONNECTID> with the connectId provided by Maxar. Parameters are not required to be in the same order as shown above. |
Understanding URLThe URL shown above contains Base URL and few parameters as explained in Request Parameters. The key parameter for this request is "request=GetCapabilities" which fetches the capabilities of Web Coverage Service and response in the form of XML data.
WMS GetCapabilities Request ParametersName | Value | Short Description |
|---|
| SERVICE* | WMS | See Service. |
| REQUEST* | GetCapabilities | The value for this parameter should always be "GetCapabilities" for step 1. |
| VERSION | 1.1.1 | See Version. |
| CONNECTID* | <CONNECTID> provided by Maxar | Value for this parameter is a unique 32-digit alphanumeric value given by Maxar (see Connect ID). A valid Connect ID is mandatory for every request. |
* mandatory parameter
ResponseIn response to a GetCapabilities request, the WMS server produces an XML document. This document contains the WMS server's service metadata; describes all the operations it supports; and provides information about available Maps. The client application has to parse the XML capabilities document to retrieve the necessary information used to request a Map. The Document Object Model (DOM) is a widely-used and efficient XML parser, which represents the XML document as a tree of nodes that can easily be edited with its standard interfaces.
The response XML contains:
- WMS Service details (e.g. Name, Title, and URL).
- Contact Information (e.g. Person, Organization, Address, Telephone, Fax and Email).
- WMS Capabilities (e.g. GetCapabilities, GetMap, GetFeatureInfo and GetLegendGraphic) along with respective formats and URLs.
- Layers such as Imagery and ImageryFootprint and Bounding Box details.
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<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<!-- DOCTYPE WMT_MS_Capabilities [...] -->
<WMT_MS_Capabilities updateSequence="102" version="1.1.1">
<Service>
<Name>OGC:WMS</Name>
<Title>Maxar Web Map Service</Title>
<Abstract />
<KeywordList>
<Keyword>WFS</Keyword>
<Keyword>WMS</Keyword>
</KeywordList>
<OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.digitalglobe.com"/>
<ContactInformation>
<ContactPersonPrimary>
<ContactPerson>Customer Service Department</ContactPerson>
<ContactOrganization>Maxar</ContactOrganization>
</ContactPersonPrimary>
<ContactPosition>Customer Service Department</ContactPosition>
<ContactAddress>
<AddressType>Work</AddressType>
<Address />
<City />
<StateOrProvince />
<PostCode />
<Country />
</ContactAddress>
<ContactVoiceTelephone>800.496.1225</ContactVoiceTelephone>
<ContactFacsimileTelephone>303.684.4562</ContactFacsimileTelephone>
<ContactElectronicMailAddress>
info@maxar.com
</ContactElectronicMailAddress>
</ContactInformation>
<Fees>NONE</Fees>
<AccessConstraints>NONE</AccessConstraints>
</Service>
<Capability>
<Request>
<GetCapabilities>
<Format>application/vnd.ogc.wms_xml</Format>
<DCPType>
<HTTP>
<Get>
<OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://services-test.digitalglobe.com/mapservice/wmsaccess?SERVICE=WMS&connectId=<CONNECTID>&"/>
</Get>
<Post>
<OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://services-test.digitalglobe.com/mapservice/wmsaccess?SERVICE=WMS&connectId=<CONNECTID>&"/>
</Post>
</HTTP>
</DCPType>
</GetCapabilities>
<GetMap>
<Format>image/png</Format>
<Format>image/geotiff</Format>
<Format>image/jpeg</Format>
<Format>image/vnd.jpeg-png</Format>
<DCPType>
<HTTP>
<Get>
<OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://services-test.digitalglobe.com/mapservice/wmsaccess?SERVICE=WMS&connectId=<CONNECTID>&"/>
</Get>
</HTTP>
</DCPType>
</GetMap>
[...]
</Request>
<Exception>
<Format>application/vnd.ogc.se_xml</Format>
<Format>application/vnd.ogc.se_inimage</Format>
</Exception>
<VendorSpecificCapabilities>
<Profiles>
<Profile>Color_Infrared_Profile</Profile>
<Profile>Legacy_Profile</Profile>
<Profile>Cloud_Cover_Profile</Profile>
<Profile>Accuracy_Profile</Profile>
<Profile>Currency_Profile</Profile>
<Profile>Currency_RGB_Profile</Profile>
<Profile>True_Currency_Profile</Profile>
<Profile>Global_Currency_Profile</Profile>
<Profile>Consumer_Profile</Profile>
<Profile>Classic_Color_Consumer_Profile</Profile>
<Profile>Color_Consumer_Profile</Profile>
<Profile>MyDG_Consumer_Profile</Profile>
<Profile>MyDG_Color_Consumer_Profile</Profile>
<Profile>Default_Profile</Profile>
<Profile>Cloud_Cover_Currency_Profile</Profile>
</Profiles>
<FeatureCollection>featureCollection</FeatureCollection>
</VendorSpecificCapabilities>
<UserDefinedSymbolization SupportSLD="1" UserLayer="1" UserStyle="1" RemoteWFS="1"/>
<Layer cascaded="0" queryable="0" opaque="0" noSubsets="0">
<Name>DigitalGlobe:Imagery</Name>
<Title>DigitalGlobe:Imagery</Title>
<Abstract>
Dynamic Raster Layer with content based on Membership
</Abstract>
<KeywordList />
<SRS>EPSG:4326</SRS>
<LatLonBoundingBox maxy="90.0" maxx="180.0"
miny="-90.0" minx="-180.0" />
<ScaleHint max="1000000" min="1" />
</Layer>
<Layer cascaded="0" queryable="0" opaque="0" noSubsets="0">
<Name>DigitalGlobe:ImageryFootprint</Name>
<Title>DigitalGlobe:ImageryFootprint</Title>
<Abstract>Vector Layer based on generic</Abstract>
<KeywordList />
<SRS>EPSG:4326</SRS>
<LatLonBoundingBox maxy="90.0" maxx="180.0"
miny="-90.0" minx="-180.0" />
<ScaleHint max="1000000" min="1" />
</Layer>
</Layer>
</Capability>
</WMT_MS_Capabilities>
[...]
Step 2
The client can request GetMap with the Map server's capabilities information in order to get a Map image. The Maxar WMS supports Maps in these formats:
| https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetMap&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&LAYERS=DigitalGlobe:Imagery&format=image/jpeg Note: Replace <CONNECTID> with the connectId provided by Maxar. Parameters are not required to be in the same order as shown above. |
Understanding URLThe URL shown above contains a Base URL and vital parameters as explained in Request Parameters.
The key parameter for this request is "request=GetMap" which fetches the Map image for the specified BBOX and responses with PNG, JPEG, or GeoTIFF data based on the format parameter value.
URL PARAMETERS for WMS GETMAP REQUESTName | Parameter Value | Short Description |
|---|
CONNECTID* | <CONNECTID>, provided by Maxar | Value for this parameter is a unique 32-digit alphanumeric value given by Maxar (see Connect ID). A valid Connect ID is mandatory for every request. |
| SERVICE* | WMS | See Service. |
| REQUEST* | GetMap | The value for this parameter should always be "GetMap" for
step 2. |
| VERSION | 1.1.1 | See Version. |
SRS* | One of: - EPSG:4326
- EPSG:3395
- EPSG:3857
- AUTO:42004
| This parameter is optional. Default projection will be taken if the parameter is not used in URL. See SRS (Spatial Reference System). A complete list of supported values is found in the GetCapabilities response. |
| BBOX* | 73.8854994266476, 40.6341176876158, - 73.8606463081034, 40.6501752378911 (Above BBOX value represents an area from New York) | This defines the user's area of interest. This parameter
should be provided in the GetMap request URL to define the
geospatial region and get the corresponding Map. See Bounding Box (BBOX). |
WIDTH and HEIGHT* | WIDTH=1102 HEIGHT=712 | Width and height specify the requested Map image size. Width and Height values should be proportional to the BBOX value. |
LAYERS* | DigitalGlobe:Imagery (or) DigitalGlobe:ImageryFootprint | Imagery outputs the raster data and ImageryFootprint gives vector data for the given BBOX. The user can always use both of these layers as list parameter values (comma-separated). The last value in the list will be stacked over the previous and therefore visible on the screen. See WMS Layers. |
FORMAT* | image/jpeg image/png (or) image/geotiff | Defines the output image's format. |
ResponseIn response to a GetMap request, the Maxar WMS server returns a Map in the requested format (i.e. PNG or JPEG). Based on the requested layer, the response produces the corresponding image. WMS supports two different layers, namely Imagery and ImageryFootprint. Imagery produces a raster image while ImageryFootprint outputs vector data. The image below shows the Response Image (raster data) for the GetMap request URL shown above.
Response Image for GetMap Request URL
Step 3
The client can request GetFeatureInfo by specifying a point on the Map to receive more geographic Feature information. This is an optional operation supported for those layers that have the attribute queryable="1". The canonical use case for GetFeatureInfo is that a user sees the response of a Map request and chooses a point on that Map for which to obtain more information.
The basic operation provides the ability for a client to specify which pixel is being asked about, which layer(s) should be investigated, and in what format the information should be returned. Because the WMS protocol is stateless, the GetFeatureInfo request indicates to the WMS what Map the user is viewing by including most of the original GetMap request parameters (all but VERSION and REQUEST). From the spatial context information (BBOX, SRS, WIDTH, HEIGHT) in that GetMap request, along with the X,Y position the user chose, the WMS can possibly return additional information about that position.
| https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetFeatureInfo&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&QUERY_LAYERS=DigitalGlobe:ImageryFootprint&X=200&Y=150&LAYERS=DigitalGlobe:ImageryFootprint Note: Replace <CONNECTID> with the connectId provided by Maxar. Parameters are not required to be in the same order as shown above. |
Understanding URLThe URL shown above contains the Base URL and vital parameters as explained in the table below. The key parameter for this request is "request=GetFeatureInfo", which fetches the Feature information or metadata at a particular pixel location (identified with X and Y values) on the Map for the specified BBOX and within valid QUERY_LAYERS. The WMS server responds with a .txt file which contains the requested Feature information such as Feature ID, % of cloud cover, age of image in days, image acquisition date, source of image, and so on.
URL PARAMETERS for WMS GETMAP REQUESTName | Parameter Value | Short Description |
|---|
CONNECTID* | <CONNECTID>, provided by Maxar | Value for this parameter is a unique 32-digit alphanumeric value given by Maxar (see Connect ID). A valid Connect ID is mandatory for every request. |
| SERVICE* | WMS | See Service. |
| REQUEST* | GetFeatureInfo | The value for this parameter should always be "GetFeatureInfo" for
step 2. |
| VERSION | 1.1.1 | See Version. |
SRS* | One of: - EPSG:4326
- EPSG:3395
- EPSG:3857
- AUTO:42004
| This parameter is optional. Default projection will be taken if the parameter is not used in URL. See SRS (Spatial Reference System). A complete list of supported values is found in the GetCapabilities response. |
| BBOX* | 73.8854994266476, 40.6341176876158, - 73.8606463081034, 40.6501752378911 (Above BBOX value represents an area from New York) | This defines the user's area of interest. This parameter
should be provided in the GetFeatureInfo request URL to define the
geospatial region and get the corresponding Map. See Bounding Box (BBOX). |
WIDTH and HEIGHT* | WIDTH=1102 HEIGHT=712 | Width and height specify the requested Map image size. Width and Height values should be proportional to the BBOX value. |
LAYERS* | DigitalGlobe:ImageryFootprint | ImageryFootprint gives vector data for the given BBOX. The user should always use this layer only to get the Feature information or metadata. |
QUERY_LAYERS* | DigitalGlobe:ImageryFootprint | ImageryFootprint gives vector data for the given BBOX. The user should always use this layer only to get the Feature information or metadata. See WMS Layers. |
X and Y* | X=200 and Y=150 | X and Y represent the coordinates of a particular pixel on that particular region (depends on BBOX and WIDTH and HEIGHT). |
ResponseIn response to a GetFeatureInfo request, the Maxar WMS server produces a text file with the details of a requested Feature. The response for the GetFeatureInfo request URL shown above is as follows:
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Results for FeatureType 'ImageryFootprint':
--------------------------------------------------------------------------------
featureId = b101db8114077461dc308cc8045834ba
geometry = [GEOMETRY (Polygon) with 5 points]
offNadirAngle = 4.1947756
sunElevation = 67.1707
cloudCover = 0.0
sunAzimuth = 150.24382
source = WV02
sourceUnit = Strip
productType = Pan Sharpened Natural Color
groundSampleDistance = 0.5
groundSampleDistanceUnit = Meter
dataLayer = country_coverage
legacyDescription =
outputMosaic = false
colorBandOrder = RGB
assetName = FINISHED
assetType = PRODUCT_GEOMETRY
legacyId = 1030010005C7FE00
factoryOrderNumber = 052411716-20
acquisitionDate = 2010-05-20 16:04:36.352
perPixelX = 4.499999992E-6
perPixelY = -4.499999999E-6
crsFromPixels = EPSG:4326
URL =
ageDays = 193
formattedDate = 2010-05-20
CE90Accuracy = 10.2 meters
RMSEAccuracy = 4.75 meters
ingestDate = 2010-10-15 03:36:00.349574
spatialAccuracy = 1:12,000
earliestAcquisitionDate =
latestAcquisitionDate =
Service Exceptions
The WMS server throws an exception when a client request is invalid or the requested data is not available. The WMS server sends the exception as an XML document with content that varies in different scenarios and operation failures.
The EXCEPTIONS parameter in a request indicates the format in which the client wishes to be notified of Service Exceptions. The only value of the EXCEPTIONS parameter that is defined for the WMS Web Service is "application/vnd.ogc.se_xml", which means "Service Exception XML". The error messages appear as <ServiceException> elements within the <ServiceExceptionReport> in Service Exception XML.
The table below shows the WMS exception codes as defined by OGC and implemented by Maxar.
WMS Exception Codes and their MeaningsException Code | Meaning |
|---|
| InvalidFormat | The request contains a format not offered by the service instance |
| InvalidSRS | The request contains an SRS not offered by the service instance for one or more of the layers in the request. |
| LayerNotDefined
| The request is for a layer not offered by the service instance. |
StyleNotDefined | The request is for a layer in a style not offered by the service instance. |
LayerNotQueriable | GetFeatureInfo request is applied to a layer which is not declared queryable. |
CurrentUpdateSequence | Value of (optional) updateSequence parameter in GetCapabilities request is equal to current value of Capabilities XML update sequence number. |
InvalidUpdateSequence | Value of (optional) updateSequence parameter in GetCapabilities request is greater than current values of Capabilities XML update sequence number. |
The following sample requests generate different service exceptions:
Example Request 1 | https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetMap&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&LAYERS=DigitalGlobe:Imagery&format=image/bmp |
The above request contains the parameter "format=image/bmp", which is not supported by WMS for the GetMap operation. This request throws the "InvalidFormat" exception shown below:
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<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport [...]>
<ServiceExceptionReport version="1.1.1">
<ServiceException code="InvalidFormat">
There is no support for creating maps in image/bmp format
</ServiceException>
</ServiceExceptionReport>
Example Request 2 | https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetMap&version=1.1.1&SRS=EPSG:40026&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&LAYERS=DigitalGlobe:Imagery&format=image/jpeg |
The above request contains the parameter "SRS=EPSG:40026", which is not supported by WMS. This request throws the "InvalidSRS" exception shown below:
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<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport (View Source for full doctype...)>
<ServiceExceptionReport version="1.1.1">
<ServiceException code="InvalidSRS">
Error occurred decoding the espg code EPSG:40026 No code "EPSG:40026" from authority "European Petroleum Survey Group" found for object of type "IdentifiedObject".
</ServiceException>
</ServiceExceptionReport>
Example Request 3 | https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetMap&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&LAYERS=DigitalGlobe:CitySphereTileService&format=image/jpeg |
The parameter "LAYERS=DigitalGlobe:CitySphereTileService" in the above request is trying to get an image from the CitySphereTileService layer, which is not supported by WMS. This request throws the "LayerNotDefined" exception shown below:
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<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport (View Source for full doctype...)>
<ServiceExceptionReport version="1.1.1">
<ServiceException code="LayerNotDefined">
Could not find layer DigitalGlobe:CitySphereTileService
</ServiceException>
</ServiceExceptionReport>
Example Request 4 | https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetFeatureInfo&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&X=200&Y=150&LAYERS=DigitalGlobe:ImageryFootprint |
The GetFeatureInfo request above does not contain the "QUERY_LAYERS" parameter which is mandatory in this operation. As a result, the request throws the "No QUERY_LAYERS" exception shown below:
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<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport (View Source for full doctype...)>
<ServiceExceptionReport version="1.1.1">
<ServiceException
code="org.vfny.geoserver.wms.requests.GetFeatureInfoKvpReader">
No QUERY_LAYERS has been requested, or no queryable layer in the request anyways
</ServiceException>
</ServiceExceptionReport>
Example Request 5 | https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetFeatureInfo&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&QUERY_LAYERS=DigitalGlobe:Imagery&X=200&Y=150&LAYERS=DigitalGlobe:ImageryFootprint |
The GetFeatureInfo request above contains an incorrect value for the QUERY_LAYERS parameter which must be ImageryFootprint. As a result, the request throws the Internal error occurred exception shown below:
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<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport (View Source for full doctype...)>
<ServiceExceptionReport version="1.1.1">
<ServiceException code="Internal error occurred" />
</ServiceExceptionReport>
Example Request 6 | https://evwhs.digitalglobe.com/mapservice/wmsaccess?connectId=<CONNECTID>&SERVICE=WMS&REQUEST=GetFeatureInfo&version=1.1.1&SRS=EPSG:4326&BBOX=-73.8854994266476,40.6341176876158,-73.8606463081034,40.6501752378911&WIDTH=1102&HEIGHT=712&QUERY_LAYERS=DigitalGlobe:ImageryFootprint&LAYERS=DigitalGlobe:ImageryFootprint |
The GetFeatureInfo request does not contain the mandatory parameters X and Y. As a result, it throws the "X and Y incorrectly specified" exception shown below:
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<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport (View Source for full doctype...)>
<ServiceExceptionReport version="1.1.1">
<ServiceException>
X and Y incorrectly specified
</ServiceException>
</ServiceExceptionReport>
WMS Layers
WMS LayersOGC Layer | Description |
|---|
| Imagery | Imagery for all data layers available to the account, with the default display for a location determined by stacking profile. |
| ImageryFootprint | Vector representation of the raster Coverage available in the Imagery Layer. |
| CrisisEvent
| Imagery from the FirstLook Product, with the most recent image displayed by default. |
CrisisEventFootprint | Vector representation of the raster Coverage available in the CrisisEvent Layer. |
LegacyCountryCoverage | Imagery from the DGWS 1.0 system, formerly known as Layerstack 49. Stacking profiles do not apply. |
LegacyCountryCoverageFootprint | Vector representation of the raster Coverage available in the LegacyCountryCoverageLayer. |
LegacyGlobalBaseMap | Imagery from the DGWS 1.0 system, formerly known as Layerstack 58. Stacking profiles do not apply. |
LegacyGlobalBasemapFootprint | Vector representation of the raster Coverage available in the LegacyGlobalBaseMap Layer. |
LegacyOilAndGasCoverage | Imagery from the DGWS 1.0 system, formerly known as Layerstack 48. Stacking profiles do not apply |
LegacyOilAndGasCoverageFootprint | Vector representation of the raster Coverage available in the LegacyOilAndGasCoverage Layer. |
API Reference
The API reference provides a list of all possible request parameters for every WMS operation as well as detailed
information about corresponding response.
The client should provide the respective information in a Key-Value Pair (KVP) format for every WMS request, where
the "name" field is the key, and the "value" field is the value; the data is supplied in the format "key=value"; for
example, "service=WMS".
| The parameter name COVERAGE_CQL_FILTER is used for GetMap requests and the parameter name CQL_FILTER is used for GetFeatureInfo requests. |
GetMapThe following table shows all possible request parameters for GetMap operation of WMS server.
PARAMETERS OF A WMS GETMAP REQUESTName | Value | Short Description |
|---|
| SERVICE* | WMS | Web Map Service |
| REQUEST* | GetMap | Request name |
| VERSION | 1.1.1 | Request version |
LAYERS* | One or more of the available data layers; each is prefixed with "Maxar:" Layers supported by WMS service are: - DigitalGlobe: Imagery
- DigitalGlobe: ImageryFootprint
- crisis_event (FirstLook - Natural and human caused disasters)
- country_coverage (Global Basemap Countries)
- metro (Global Basemap Cities)
- aerial_cells (Global Basemap Aerial Cells. U.S. and Western Europe Coverage only)
- aerial_markets (GBM Aerial Markets/urban areas. US and Western EU)
- aerial_cir_cells (Color infrared version of aerial cells)
- aerial_cir_markets (Color infrared version of aerial markets)
- monitoring (AssuredLook – monitoring of selected sites)
| The layers available from the Online Catalogs. If more than one layer is requested they should be in a comma-separated list. |
STYLES* | A style definition for each requested layer; valid styles are defined in the GetCapabilities response: Example value: dg_ras | If multiple layers are requested, the styles parameter is a comma-separated list. If the default style is desired, the "STYLES" parameter must still be included, but the value(s) may be left empty. |
SRS* | One of: - EPSG:4326
- EPSG:3395
- EPSG:3857
- AUTO:42004
| Only one SRS is supported. If SRS is not specified, EPSG:4326 is the default value in which the Map will be returned. 4326 provides tiles where latitude and longitude are treated as X/Y values. 3857 provides tiles in the spherical Mercator projection. A complete list of supported values is found in the GetCapabilities response. |
| BBOX* | Bounding box defined as: minx,miny,maxx,maxy | Bounding box of the requested Map area, in
coordinates of the requested SRS. |
WIDTH* | Integer number of pixels to be returned in the X coordinate | | If the width/height aspect is different than the BBOX ratio, this may result in a distorted Map. |
|
HEIGHT* | Integer number of pixels to be returned in the Y coordinate | | If the width/height aspect is different than the BBOX ratio, this may result in a distorted Map. |
|
FORMAT* | MIME format in which the data is to be returned: image/png image/jpeg image/geotiff | The format in which to return the Map image. |
TRANSPARENT | Binary field indicating whether the returned image should have a transparent background: FALSE: Not transparent TRUE: Transparent | Default =TRUE if not supplied |
BGCOLOR | Background color in hexadecimal format. Example: 0xFFFFFF | Default =0Xffffff if not supplied |
CONNECTID* | Character String | Value for this parameter is a unique 32-digit alphanumeric value given by Maxar (see Connect ID). A valid Connect ID is mandatory for every request. |
COVERAGE_CQL_FILTER | Filters the images included in the returned Map | When using the DigitalGlobe: ImageryFootprint layer, COVERAGE_CQL_FILTER changes to CQL_FILTER. |
| See Common Query Language. |
EXCEPTIONS | MIME type for exceptions: application/vnd.ogc.se_xml | Format in which exceptions will be reported. If not specified, default is XML. |
| FEATUREPROFILE | The current profiles include:
Accuracy_Profile
Aerial_CIR_Profile
Cloud_Cover_Profile
Consumer_Profile
Currency_Profile
Currency_RGB_Profile
Default_Profile
True_Currency_Profile
| Profiles describe the stacking rules on an
account. The user can choose a profile in a
request by specifying the featureProfile. The
most current available profiles can be found
in the GetCapabilities response. |
*mandatory parameter
GetFeatureInfoThe following table shows all possible request parameters for GetFeatureInfo operation of WMS server.
PARAMETERS OF A WMS GETFEATUREINFO REQUESTName | Value | Short Description |
|---|
| SERVICE* | WMS | Web Map Service |
| REQUEST* | GetFeatureInfo | Request name |
| VERSION | 1.1.1 | Request version |
BBOX* | Bounding box defined as: minx,miny,maxx,maxy This parameter value from the GetMap request should be repeated here. | Bounding box of the requested Map area, in coordinates of the requested SRS. |
WIDTH* | Integer number of pixels to be returned in the X coordinate. This parameter value from the GetMap request should be repeated here. | | If the width/height aspect is different than the BBOX ratio, this may result in a distorted Map. |
|
HEIGHT* | Integer number of pixels to be returned in the Y coordinate. This parameter value from the GetMap request should be repeated here. | | If the width/height aspect is different than the BBOX ratio, this may result in a distorted Map. |
|
QUERY_LAYERS* | One or more of the available WMS layers, for example: DigitalGlobe: Imagery | The layer(s) for which Feature info is being requested; if multiple layers they are in a comma-separated list. See Integration Procedure. |
LAYERS* | One or more of the available WMS layers, for example: DigitalGlobe: Imagery | The layer(s) for which Feature info is being requested; if multiple layers they are in a comma-separated list. |
INFO_FORMAT | MIME type of returned Feature info: application/vnd.ogc.gml | Mime format in which to return the Feature info; XML is the supported value. |
FEATURE_COUNT | Its value is a positive integer greater than zero. | This states the maximum number of Features for which Feature information should be returned. If this parameter isn't specified, the default value is 1. |
X* | Integer; value from 0 to specified "WIDTH" value | X coordinate (column) in pixels of Feature (measured from upper left corner=0) |
Y* | Integer; value from 0 to specified "HEIGHT" value | Y coordinate (row) in pixels of Feature (measured from upper left corner=0) |
EXCEPTIONS | MIME type for exceptions: application/vnd.ogc.se_xml | Format in which exceptions will be reported. If not specified, default is XML. |
CONNECTID* | Character String | Value for this parameter is a unique 32-digit alphanumeric value given by Maxar (see Connect ID). A valid Connect ID is mandatory for every request. |
CQL_FILTER | Filters the images included in the returned Map | See Common Query Language. |
*mandatory parameter
GetFeatureInfo Response Element | Datatype | Example Value | Description |
|---|
featureId | String | b101db8114077461dc308cc804 5834ba | The Feature ID for the Map Feature at the given (X,Y) coordinate |
acquisitionDate | String | 2009-05-27 01:20:43.63599 | The GMT of acquisition of the image used to make the product described by the Feature. |
formattedDate | Date | 2010-05-20 (YYYY-MM-DD) | The date of production or the date the image was reproduced. |
cloudCover | Float | 0.0-1.0 | The cloud cover percentage of the image described by the Feature. Example: To represent 20% cloud cover, specify 0.2. |
offNadirAngle | Float | 0.0-90.0 | The average off-nadir angle of the image strip described by the Feature. |
sunElevation | Float | 0.0-90 | The elevation angle of the sun for the image strip described by the Feature. |
sunAzimuth | Float | +/- 180.00 | The azimuth angle of the sun for the image strip described by the Feature. |
ageDays | Integer | Example: 29 | The number of days between the acquisitionDate and today. |
data_layer | String | country_coverage | Represents the layer to which this particular image belongs. See Integration Procedure. |
source | String | WV02 | Represents the source of the image. This value would be one of the following: - QB QuickBird
- WV01 WorldView1
- WV02 WorldView2
- Aerial Aerial Imagery
|
outputMosaic | Boolean | TRUE/FALSE | Value will be TRUE if the output is a mosaic of more than one source image. |
