For a data source to provide WMS services, you may first need to define themes and base maps, because they will become the actual service content that the map visualization server will be providing. You can use the Oracle Map Builder Tool to create the themes and base maps.

After creating themes and base maps, you can edit the wmsConfig.xml file in the WEB-INF/conf/ folder, which is the same folder for the mapViewerConfig.xml file. For example, if data sources named nedata and mvdemo are allowed to provide WMS services, the wmsConfig.xml file may contain a section similar to the following:

<?xml version="1.0" ?>
<wms_config>
   . . . . . . 
  <custom_parameters  
            host="localhost" port="80" protocol="http" 
            public_datasources="nedata, mvdemo">
    </custom_parameters>   
   . . . . . . 
</wms_config>

For changes to the wmsConfig.xml file take effect, you must restart the map visualization server.

To test the server, you can send a getCapabilities request. For example:

http://localhost:8080/mapviewer/wms?REQUEST=GetCapabilities&VERSION=1.3.0

You must define a map visualization component data source named wms, unless every incoming WMS request explicitly specifies a datasource CGI parameter. All requests that do not specify the datasource parameter are by default directed to the data source named wms. For example, the GetCapabilities request will by default list all the available themes that are in the wms data source. (To configure the information returned by a GetCapabilities request, see Customizing WMS GetCapabilities Responses.)

By default, the map visualization component uses the Oracle Spatial and Graph (SDO) native SRID (spatial reference ID) values when such information is requested in a WMS request such as GetCapabilities. The EPSG SRID values, however, are more widely used in WMS applications. To have the map visualization component use EPSG SRID values when processing WMS requests and generating responses, specify a mapping file. This mapping file is a text file that tells the map visualization component which SDO SRID values map to which EPSG SRID values. (Each pair of matching SRID values refers to the same spatial reference system.)

The mapping file contains lines where each line defines one pair of equivalent SRID values in the following format:

sdo_srid=epsg_srid

For example, the following lines define SDO SRID 8307 as equivalent to EPSG SRID 4326, and SDO SRID 81922 as equivalent to EPSG SRID 20248:

8307=4326
81922=20248

After you have created an SDO to EPSG mapping file, you can save it on the server where the map visualization component is running, and specify its location in the map visualization component configuration file using the <sdo_epsg_mapfile> element in the <wms_config> element, as explained in Customizing WMS GetCapabilities Responses.

This section describes the supported GetMap request parameters and their interpretation by the map visualization component. (Parameters that are specific to the map visualization component and not mentioned in the WMS 1.1.1 and 1.3.0 specifications are labeled Map Visualization Component-Only.) The supported parameters are in alphabetical order, with each in a separate subsection. Example C-1 shows some GetMap requests. (Each URL should be entered as a single string.)

http://localhost:8888/mapviewer/wms?REQUEST=GetMap&VERSION=1.1.1&FORMAT=image/gif&
SERVICE=WMS&BBOX=-121,37,-119,35&SRS=EPSG:4326&LAYERS=theme_demo_states,theme_
demo_counties,theme_demo_highways,theme_demo_cities&WIDTH=580&HEIGHT=500

http://localhost:8888/mapviewer/wms?REQUEST=GetMap&VERSION=1.3.0&FORMAT=image/gif&
SERVICE=WMS&BBOX=-121,37,-119,35&CRS=EPSG:4326&LAYERS=theme_demo_states,theme_
demo_counties,theme_demo_highways,theme_demo_cities&WIDTH=580&HEIGHT=500

http://localhost:8888/mapviewer/wms?request=GetMap&version=1.3.0&crs=none
&bbox=-122,36,-121,37&width=600&height=400&format=image/png&layers=theme_us_
states&mvthemes=<themes><theme%20name="theme_us_counties"/><theme%20name="theme_
us_road1"/></themes>&legend_
request=<legend%20bgstyle="fill:%23ffffff;stroke:%23ff0000"%20profile="medium"%20p
osition="SOUTH_EAST"><column><entry%20style="v.rb1"%20tab="1"/></column></legend>& 

http://localhost:8888/mapviewer/wms?request=GetMap&version=1.1.1&srs=none&bbox=-12
2,36,-121,37&width=600&height=400&format=image/png&layers=theme_us_
states&mvthemes=<themes><theme%20name="theme_us_counties"/><theme%20name="theme_
us_road1"/></themes>&legend_
request=<legend%20bgstyle="fill:%23ffffff;stroke:%23ff0000"%20profile="medium"%20p
osition="SOUTH_EAST"><column><entry%20style="v.rb1"%20tab="1"/></column></legend>&

• BASEMAP Parameter (Map Visualization Component-Only)
  
• BBOX Parameter
  
• BGCOLOR Parameter
  
• DATASOURCE Parameter (Map Visualization Component-Only)
  
• DYNAMIC_STYLES Parameter (Map Visualization Component-Only)
  
• EXCEPTIONS Parameter
  
• FORMAT Parameter
  
• HEIGHT Parameter
  
• LAYERS Parameter
  
• LEGEND_REQUEST Parameter (Map Visualization Component-Only)
  
• MVTHEMES Parameter (Map Visualization Component-Only)
  
• REQUEST Parameter
  
• SERVICE Parameter
  
• SRS (1.1.1) or CRS (1.3.0) Parameter
  
• STYLES Parameter
  
• TRANSPARENT Parameter
  
• VERSION Parameter
  
• WIDTH Parameter
  

A WMS GetCapabilities request to the map visualization component should specify only the following parameters:

• REQUEST=GetCapabilities

• VERSION=1.1.1 or VERSION=1.3.0

• SERVICE=WMS

For example:

http://localhost:8888/mapviewer/wms?REQUEST=GetCapabilities&VERSION=1.1.1&SERVICE=WMS
or
http://localhost:8888/mapviewer/wms?REQUEST=GetCapabilities&VERSION=1.3.0&SERVICE=WMS

The response is an XML document conforming to the WMS Capabilities DTD available at the following, depending on the value of the VERSION parameter (1.1.1 or 1.3.0):

http://schemas.opengis.net/wms/1.1.1/WMS_MS_Capabilities.dtd

http://schemas.opengis.net/wms/1.3.0/capabilities_1_3_0.xsd

However, the current release of the map visualization component returns an XML document containing the <Service> and <Capability> elements with the following information:

• The <Service> element is mostly empty, with just the required value of OGC:WMS for the <Service.Name> element. Support for more informative service metadata is planned for a future release of the map visualization component.

• The <Capability> element has <Request>, <Exception>, and <Layer> elements.

• The <Request> element contains the GetCapabilities and GetMap elements that describe the supported formats and URL for an HTTP GET or POST operation.

• The <Exception> element defines the exception format. The Service Exception XML is the only supported format in this release. The <Exception> element returns an XML document compliant with the Service Exception DTD, but it does not report exceptions as specified in the implementation specification. The current release simply uses the CDATA section of a <ServiceException> element to return the OMSException returned by the map visualization component server.

• The <Layer> element contains a nested set of <Layer> elements. The first (outermost) layer contains a name (WMS), a title (Oracle WebMapServer Layers by data source), and one <Layer> element for each defined data source. Each data source layer contains a <Layer> element for each defined base map and one entry for each valid theme (layer) not listed in any base map. Each base map layer contains a <Layer> element for each predefined theme in the base map.

  Themes that are defined in the USER_SDO_THEMES view, that have valid entries in the USER_SDO_GEOM_METADATA view for the base table and geometry column, and that are not used in any base map will be listed after the base maps for a data source. These themes will have no <ScaleHint> element. They will have their own <LatLonBoundingBox> and <BoundingBox> elements.

The Content-Type of the response is set to application/vnd.ogc.wms_xml, as required by the WMS implementation specification.

Because the list of layers is output by base map, a given layer or theme can appear multiple times in the GetCapabilities response. For example, the theme THEME_DEMO_STATES, which is part of the base maps named DEMO_MAP and DENSITY_MAP, appears twice in Example C-2, which is an excerpt (reformatted for readability) from a GetCapabilities response.

In Example C-2, the innermost layer describes the IMAGE_LEVEL_2 theme. The <ScaleHint> element lists the min_scale and max_scale values, if any, for that theme in the base map definition. For example, the base map definition for IMAGE_MAP is as follows:

SQL> select definition from user_sdo_maps where name='IMAGE_MAP';
 
DEFINITION
------------------------------------------------------------------------
<?xml version="1.0" standalone="yes"?>
<map_definition>
  <theme name="IMAGE_LEVEL_2" min_scale="1000.0" max_scale="0.0"/>
  <theme name="IMAGE_LEVEL_8" min_scale="5000.0" max_scale="1000.0"/>
  <theme name="MA_ROAD3"/>
  <theme name="MA_ROAD2"/>
  <theme name="MA_ROAD1"/>
  <theme name="MA_ROAD0"/>
</map_definition>

In the innermost layer, the <SRS> and <BoundingBox> elements identify the SRID and the DIMINFO information for that theme's base table, as shown in the following Spatial and Graph metadata query:

SQL> select srid, diminfo from user_sdo_geom_metadata, user_sdo_themes 
  2  where name='IMAGE_LEVEL_2' and 
  3  base_table=table_name and
  4  geometry_column=column_name ;
 
      SRID
----------
DIMINFO(SDO_DIMNAME, SDO_LB, SDO_UB, SDO_TOLERANCE)
--------------------------------------------------------------------------------
     41052
SDO_DIM_ARRAY(SDO_DIM_ELEMENT('X', 200000, 500000, .5), SDO_DIM_ELEMENT('Y', 750
000, 950000, .5))

In Example C-2, the <Layer> element for a base map has an <SRS> element and a <LatLonBoundingBox> element. The <SRS> element is empty if all layers in the base map definition do not have the same SRID value specified in the USER_SDO_GEOM_METADATA view. If they all have the same SRID value (for example, 41052), the SRS element contains that value (for example, SDO:41052). The required <LatLonBoundingBox> element currently has default values (-180,-90,180,90). When this feature is supported by map visualization component, this element will actually be the bounds specified in the DIMINFO column of the USER_SDO_GEOM_METADATA view for that layer, converted to geodetic coordinates if necessary and possible.

All layers are currently considered to be opaque and queryable. That is, all layers are assumed to be vector layers, and not GeoRaster, logical network, or image layers.

<Title>Oracle WebMapServer Layers by data source</Title>
<Layer>
 <Name>mvdemo</Name>
 <Title>Datasource mvdemo</Title>
   <Layer>
     <Name>DEMO_MAP</Name>
     <Title>Basemap DEMO_MAP</Title>
     <SRS>SDO:8307</SRS>
     <LatLonBoundingBox>-180,-90,180,90</LatLonBoundingBox>
. . .
   <Layer>
     <Name>DENSITY_MAP</Name>
     <Title>Basemap DENSITY_MAP</Title>
     <SRS>SDO:8307</SRS>
     <LatLonBoundingBox>-180,-90,180,90</LatLonBoundingBox>
       <Layer>
         <Name>THEME_DEMO_STATES</Name>
         <Title>THEME_DEMO_STATES</Title>
         <SRS>SDO:8307</SRS>
         <BoundingBox SRS="SDO:8307" minx="-180" miny="-90" maxx="180"
                      maxy="90" resx="0.5" resy="0.5"/>
         <ScaleHint min="50.0" max="4.0"/>
       </Layer>
. . .              
   </Layer>
   <Layer>
     <Name>IMAGE_MAP</Name>
     <Title>Basemap IMAGE_MAP</Title>
     <SRS>SDO:41052</SRS>
     <LatLonBoundingBox>-180,-90,180,90</ LatLonBoundingBox>
       <Layer>
         <Name>IMAGE_LEVEL_2</Name>
         <Title>IMAGE_LEVEL_2</Title>
         <SRS>SDO:41052</SRS>
         <BoundingBox SRS="SDO:41052" minx="200000" miny="500000" maxx="750000"
                    maxy="950000" resx="0.5" resy="0.5"/>
         <ScaleHint min="1000.0" max="0.0"/>
       </Layer>
. . .    
   </Layer>

This section describes the supported GetFeatureInfo request parameters and their interpretation by the map visualization component. Example C-3 shows some GetFeatureInfo requests.

The response is an XML document and the Content-Type of the response is text/xml. Example C-4 is a response to a GetFeatureInfo request in Example C-3.

Most of the following sections describe parameters supported for a GetFeatureInfo request. (Parameters that are specific to MapViewer and not mentioned in the WMS 1.1.1 specification are labeled Map Visualization Component-Only.) Specifying Attributes to Be Queried for a GetFeatureInfo Request explains how to query attributes in a GetFeatureInfo request.

http://localhost:8888/mapviewer/wms?REQUEST=GetFeatureInfo&VERSION=1.1.1&BBOX=0,-0
.0020,0.0040&SRS=EPSG:4326&LAYERS=cite:Lakes,cite:Forests&WIDTH=200&HEIGHT=100&INF
O_FORMAT=text/xml&QUERY_LAYERS=cite:Lakes,cite:Forests&X=60&Y=60

http://localhost:8888/mapviewer/wms?REQUEST=GetFeatureInfo&VERSION=1.3.0
&BBOX=0,-0.0020,0.0040&CRS=EPSG:4326&LAYERS=cite:Lakes,cite:Forests&WIDTH=200&HEIGHT=100
&INFO_FORMAT=text/xml&QUERY_LAYERS=cite:Lakes,cite:Forests&I=60&J=60

<?xml version="1.0" encoding="UTF-8" ?>
<GetFeatureInfo_Result>
  <ROWSET name="cite:Lakes">
    <ROW num="1">
      <ROWID>AAAK22AAGAAACUiAAA</ROWID>
    </ROW>
  </ROWSET>
  <ROWSET name="cite:Forests">
    <ROW num="1">
      <FEATUREID>109</FEATUREID>
    </ROW>
  </ROWSET>
</GetFeatureInfo_Result>

• GetMap Parameter Subset for GetFeatureInfo Requests
  
• EXCEPTIONS Parameter
  
• FEATURE_COUNT Parameter
  
• INFO_FORMAT Parameter
  
• QUERY_LAYERS Parameter
  
• QUERY_TYPE Parameter (Map Visualization Component-Only)
  
• RADIUS Parameter (Map Visualization Component-Only)
  
• UNIT Parameter (Map Visualization Component-Only)
  
• X and Y or I and J Parameters
  
• Specifying Attributes to Be Queried for a GetFeatureInfo Request
  

To add a WMS map theme to the current map request using the map visualization component XML API, use the <wms_getmap_request> element in a <theme> element.

For better performance, the <wms_getmap_request> element should be used only to request a map image from a Web Map Server (WMS) implementation. That is, the <service_url> element in a <wms_getmap_request> element should specify a WMS implementation, not a map visualization component instance. If you want to specify a map visualization component instance (for example, specifying <service_url> with a value of http://mapviewer.mycorp.com:8888/mapviewer/wms), consider using a MapViewer predefined theme or a JDBC theme in the <themes> element instead of using a <wms_getmap_request> element.

The following example shows the general format of the <wms_getmap_request> element within a <theme> element, and it includes some sample element values and descriptive comments:

<themes>
  <theme>
     <wms_getmap_request isBackgroundTheme="true">
           <!-- The wms_getmap_request theme is rendered in the order it 
                 appears in the theme list unless isBackgroundTheme is "true". 
           -->
          <service_url> http://wms.mapsrus.com/mapserver </service_url>
          <version> 1.1.1 </version>
            <!-- version is optional. Default value is "1.1.1".
            -->
          <layers> Administrative+Boundaries,Topography,Hydrography </layers>
           <!— layers is a comma-delimited list of names. 
              If layer names contain spaces, use '+' instead of a space -->
           <!— styles is optional. It is a comma-delimited list, and it must
              have the same number of  names as the layer list, if specified. 
              If style names contain spaces, use '+' instead of a space -->
          <styles/>
          <srs> EPSG:4326 </srs>
          <format> image/png </format>
          <transparent> true </transparent>
          <bgcolor> 0xffffff </bgcolor>
          <exceptions> application/vnd.ogc.se_inimage </exceptions>
          <vendor_specific_parameters>
               <!-- one or more <vsp> elements each containing 
                     a <name> <value> pair  -->
               <vsp>
                    <name> datasource </name>
                    <value> mvdemo </value>
                 </vsp>
          <vendor_specific_parameters>
     <wms_getmap_request>
  </theme>
</themes>

The following attribute and elements are available with the <wms_getmap_request> element:

• The isBackgroundTheme attribute specifies whether or not this theme should be rendered before the vector layers. The default value is false.

• The <service_url> element specifies the URL (without the service parameters) for the WMS service. Example: http://my.webmapserver.com/wms

• The <version> element specifies the WMS version number. The value must be one of the following: 1.0.0, 1.1.0, 1.1.1 (the default), or 1.3.0.

• The <layers> element specifies a comma-delimited list of layer names to be included in the map request.

• The <styles> element specifies a comma-delimited list of style names to be applied to the layer names in layers.

• The <srs> element specifies the coordinate system (spatial reference system) name. The default value is EPSG:4326.

• The <format> element specifies the format for the resulting map image. The default value is image/png.

• The <transparent> element specifies whether or not the layer or layers being added should be transparent in the resulting map image. The default value is false. To make the layer or layers transparent, specify true.

• The <bgcolor> element specifies the RGB value for the map background color. Use hexadecimal notation for the value, for example, 0xAE75B1. The default value is 0xFFFFFF (that is, white).

• The <exceptions> element specifies the format for server exceptions. The default value is application/vnd.ogc.se_inimage.

• The <vendor_specific_parameters> element contains one or more <vsp> elements, each of which contains a <name> element specifying the parameter name and a <value> element specifying the parameter value.

Example C-5 shows the <wms_getmap_request> element in a map request.

<?xml version="1.0" standalone="yes"?>
<map_request
  title="Raster WMS Theme and Vector Data"
  datasource="mvdemo" srid="0"
  width="500"
  height="375"
  bgcolor="#a6caf0"
  antialiase="true"
  mapfilename="wms_georaster" format="PNG_URL">
  <center size="185340.0">
    <geoFeature>
      <geometricProperty typeName="center">
        <Point>
          <coordinates>596082.0,8881079.0</coordinates>
        </Point>
      </geometricProperty>
    </geoFeature>
  </center>
  <themes>
    <theme name="WMS_TOPOGRAPHY" user_clickable="false"  >
       <wms_getmap_request isBackgroundTheme="true">
         <service_url> http://wms.mapservers.com:8888/mapserver/wms </service_url>
         <layers> TOPOGRAPHY </layers>
         <srs> EPSG:29190 </srs>
         <format> image/png </format>
         <bgcolor> 0xa6caf0 </bgcolor>
         <transparent> true </transparent>
         <vendor_specific_parameters>
           <vsp>
              <name> ServiceType </name>
              <value> mapserver </value>
           </vsp>
         </vendor_specific_parameters>
       </wms_getmap_request>
    </theme>
    <theme name="cl_theme" user_clickable="false">
       <jdbc_query  spatial_column="geom" render_style="ltblue" 
         jdbc_srid="82279" datasource="mvdemo"
         asis="false">select geom from classes where vegetation_type = 'forests'
       </jdbc_query>
     </theme>
  </themes>
  <styles>
    <style name="ltblue">
      <svg width="1in" height="1in">
       <g class="color" 
          style="stroke:#000000;stroke-opacity:250;fill:#33ffff;fill-opacity:100">
          <rect width="50" height="50"/>
       </g>
      </svg>
    </style>
  </styles>
</map_request>

The predefined XML definition for a WMS theme uses the same structure of the parameters in XML API for Adding a WMS Map Theme, and adds the optional capabilities_url attribute, which is used by Map Builder when editing a WMS theme. If the capabilities_url attribute is defined, Map Builder will issue a GetCapabilities request to populate some UI elements in the editor page.

Example C-6 shows how to create a predefined WMS theme in the metadata. The base table and base column names can be any values, and in this example 'WMS' is used for both.

INSERT INTO user_sdo_themes  VALUES (
  'PRED_WMS_THEME',
  'WMS data',
  'WMS',
  'WMS',   '<?xml version="1.0" standalone="yes"?>
   <styling_rules theme_type="wms">
     <service_url> http://sampleserver1b.arcgisonline.com/arcgis/services/Specialty/ESRI_StateCityHighway_USA/MapServer/WMSServer </service_url>
     <layers> 0,1,2 </layers>
     <version> 1.3.0 </version>
     <srs> CRS:84 </srs>
     <format> image/png </format>
     <bgcolor> 0xA6CAF0 </bgcolor>
     <transparent> false </transparent>
     <styles> +,+,+ </styles>
     <exceptions> xml </exceptions>
     <capabilities_url> http://sampleserver1.arcgisonline.com/ArcGIS/services/Specialty/ESRI_StateCityHighway_USA/MapServer/WMSServer? </capabilities_url>
   </styling_rules>');

For a WMS server that requires authentication for access to the WMS data, the following must be included in the theme definition:

• <user> element specifying the user name

• <password> element specifying the user password

  If you use the Map Builder tool to create a WMS map theme, the password value will be automatically encrypted. Figure C-1 shows the use of the Map Builder tool to create a WMS theme with authentication information. In this figure, the Authentication option is checked (enabled), and User and Password are specified.

  Figure C-1 Using Map Builder to Specify Authentication with a WMS Theme

  
  Description of "Figure C-1 Using Map Builder to Specify Authentication with a WMS Theme"

Example C-7 shows how to create a WMS theme that includes authentication information.

<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="wms">
    <service_url> http://localhost:7001/mapviewer/wms </service_url>
    <user> wmsuser </user>
    <password> ******* </password>
    <layers> THEME_DEMO_STATES </layers>
    <version> 1.1.1 </version>
    <srs> EPSG:4326 </srs>
    <format> image/png </format>
    <bgcolor> 0xA6CAF0 </bgcolor>
    <transparent> true </transparent>
    <exceptions> application/vnd.ogc.se_xml </exceptions>
    <vendor_specific_parameters>
        <vsp>
            <name> datasource </name>
            <value> mvdemo </value>
    </vsp>
  </vendor_specific_parameters>
    <capabilities_url> http://localhost:7001/mapviewer/wms? </capabilities_url>
</styling_rules>

The main map visualization component configuration file has a section to customize some information for GetCapabilities responses (see Customizing WMS GetCapabilities Responses). However only a limited number of properties that can be defined in that main map visualization component configuration file, and no customization can be done for several attributes that a layer can have in GetCapabilities response.

Effective with Release 12.1.3, a WMS configuration file (wmsConfig.xml) has been added to the map visualization component. Any settings defined in this WMS configuration file will override similar WMS settings defined in the main map visualization component configuration file.

The wmsConfig.xml can include the following.

• Custom WMS Capabilities Parameters (<custom_parameters> Element)
  
• Custom WMS Capabilities Service Attributes (<service_attributes> Element)
  
• Custom WMS Layer Attributes (<layer_attributes> Element)
  
• Custom WMS Feature Information (<get_feature_info> Element)